FRC CAD Collection - Blog - Link - Submission Form - CD
We created a simple system for collecting public CAD models of FRC robots and mechanisms.
The FRC CAD Collection currently has over 450 links to robots from almost 200 teams.
Looking through the CAD of completed robots is one of the best ways to get better at designing FRC robots. You can be inspired by past mechanisms and build methods of teams around the world many you may never be able to see in person.
CADcollection.Spectrum3847.org
We have added multiple new parts and a new mechanism example to the Protopipe system. We have included printable clamps, motor mounts, new connectors, drill adapters, and some small versions of previous connectors. We have also included an adapter block that allows you to combine HYPEblocks, a prototyping system made by FRC#5254 HYPE with protopipe elements.
Looking through the CAD of completed robots is one of the best ways to get better at designing FRC robots. You can be inspired by past mechanisms and build methods of teams around the world many you may never be able to see in person.
CADcollection.Spectrum3847.org
Protopipe Additions - Protopipe.Spectrum3847.org - CAD Files
We have added multiple new parts and a new mechanism example to the Protopipe system. We have included printable clamps, motor mounts, new connectors, drill adapters, and some small versions of previous connectors. We have also included an adapter block that allows you to combine HYPEblocks, a prototyping system made by FRC#5254 HYPE with protopipe elements.
Updated Guide to the FRC MCC
We updated our guide to the FRC MCC with new resources and tips. We added example MCCs from the 2019 season. We have added a section on sensors and counterbalancing mechanisms. We also updated most of the links and added new vendors to the recommended purchases.
Updated Spectrum Design Sheet
We have added Falcon 500s and both NEOs and NEO 550s to the mechanical section. We have reorganized several of the pages based on how we used it during the 2019 season. We have improved the BOM section and added a parts organization sheet.
This sheet is how we organize our robot construction and helps us design mechanisms without having to re-lookup information over and over throughout the process.
FRC Maintenance Guide
This is the first year teams can do extensive maintenance and cleaning of their robots between events. Ideally, your robot should be squeaky clean and running at peak performance at the start of each event. We started working on a Maintenance guide to use internally but decided to make it public so that other teams could benefit as well.
X-Ray 2019 Robot and Code
Below are our CAD and Code for our 2019 Robot X-Ray
Notes/Research
These are two very rough documents. These are just research docs for two different things we were interested in during the off-season.
- Large aluminum pneumatic storage tanks
- For robots that use a large amount of air, these ~2 gallon air tanks can be more weight-efficient than the plastic tanks teams often use.
- 6" Pneumatic Tires
- We wanted to find a 6" pneumatic tire that could be used in a dead axle drive setup. There a lot of great options, some of our notes are in this document.
Other Spectrum Resources
- Recommended Reading - This document is continually updated.
- Blog - Our 2020 Build Blog will begin tomorrow.
- Photo Gallery & Mechanism Library
- 2019 Resource Collection
- 2018 Resource Collection
- Spectrum
January 5, 20202020 Day 1: Rules and Inspiration
2020 Infinite Recharge
Below is the game animation for the 2020 FRC Game Infinite Recharge.
Rules
Most of our first day of build season was reading the rules for Infinite Recharge. We need everyone that is going to be helping design the robot to understand the game rules and the robot rules so they can help in that challenge.
The full manual can be found here - https://www.firstinspires.org/resource-library/frc/competition-manual-qa-system
Humans Play Infinite Recharge
We often have our team play the game out as if they were robots. It's mostly just for fun and it reinforces some of the field locations and names of the field objects. We apologize for the audio, filmed quickly on a phone.
Robots that inspired us today
2006 Robots - 217
2012 Robots - 971, 341, 254, 33, 118
2016 Robots - 3476, 1241, 33 (hood)
2018 Robots - 118(forks), 148 (wrangler)
We were looking at various ball paths and intakes from 2012 & 2016 robots that we may be able to use ideas from this season. We were also looking at various ways to possibly lift a partner off the ground with our climb as well.
Basic MCC Discussion
Our initial MCC (Minimum Competitive Concept) thoughts,
- low goal, human feed and simple floor intake through a bumper gap (over bumper is harder)
- hook flip out style climb that deploys and then you can winch up. Multiple robots in 2018 did this.
- no color wheel manipulation, it takes too many balls scored before this becomes valuable.
- Spectrum
January 6, 20202020 - Day 2
Climbing is incredibly valuable
If you are thinking about which tasks on the field to do, climbing is the most beneficial after only being able to drive successfully around the field and over the small barriers.
- At 25 points (20+ over just parking), it is worth ~7 balls in the inner goal or 20 balls in the low goal.
- It can happen very quickly at the end of the match, leaving you time to do other teams like score balls, feed balls, & play defense.
- It is points that only your robot can get. Your partners can pick up and score balls that you don't, they might be able to use the control panel to score points, but the 20+ points for you being off the ground requires you to be there.
- If you and one other person on, your alliance can climb and balance your alliance receives a ranking point.
The climb does not have to be difficult. This is the first time in some time where the only requirement for climb points is that your robot must be off the ground. (2013 was the last). If you are willing to be a tall robot, you can fold out an arm with a short (<8") pneumatic cylinder and use that to lift you 4"+ off the floor. There are also ways that you can climb be getting a hook on to the bar and using a winch to pull yourself. There are countless other options, but doing one of them successfully will make you much more likely to be picked for eliminations.
Control Panel Tasks are less valuable
In contrast to climbing, the control panel tasks are less valuable, and your team should strongly consider limiting the number of resources you devote to this task.
- While there are a lot of points (35) associated with these tasks. Your alliance is required to score a lot of balls before these tasks ever become an option for you to get points. (29+ and 49+ balls) These ball counts will be rare in qualifications matches (and probably playoff matches as well) at many events around the world. You can be the best control panel robot in the world, but if you can't score enough balls to charge the 2nd and 3rd phase, you'll never be able to use your skill.
- Even if your alliance is able to score enough balls, only one member of each alliance is needed to complete the tasks. Strongly consider where that robot should be your team, or if this is a task, you can leave to another member of your alliance.
Building Field Elements
We have started building our field elements. Working to make sure we can interact with our team elements in similar ways that we will be able to interact with the real field.
Robots that inspired us today
2006 Robots - 111 (Rack & Pinion Hood)
2012 Robots - 33 (linkage Hood, CD7 Intake, and J shooter path), 118 (intake only has grip in the middle)
2013 Robots - 1986 (Climber), 254 (climber)
2016 Robots - 195(scissor lift), 2056(climber)
2017 Robots - 971(rack hood), 33(accelerator rollers), 5803 (ball path)
2018 Robots - 33 (double reverse 4-bar), 125 & 1323(buddy climbs), 2056 (forks)
2019 Robots - 3940 (floating roller on intake)
If you're looking for some inspiration, here is a good place to see photos of some Aim High 2006 robots.
Pictures - http://www.firstrobotpics.com/?page_id=49
Sketch of the Day
A long robot (32-34") can store 5 balls in a line before entering a shooter.
- Spectrum
January 6, 20202020 - Day 3 - Starting some tests
Today's Tests
Bump crossing tests - CG is important and braking hard is bad
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-VQ2CwLV/A
Low CG and CG at the front of you robot handles the bumps better. Also this chassis has pneumatic tires.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-v9ftd6p/A
Intake Test
Protopipe has proved very useful for quickly making intake tests.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-CBtkmGp/A
Drawer Slide Elevator Test
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-SVGDst4/A
More videos and photos of these tests can be found on our photo gallery Photo.Spectrum3847.org - 2020 Build Season Gallery
Robots that inspired us today
2009 - 67 (Multi ball shooter)
2012 - 48, 341 (Photo Gallery), 548 & 330 (shooter on a pivot)
2013 - 33(Frisbee path), 987 (gas springs on climber), 1986 (climber)
2014 - 2590 (ratchet)
2017 - 319 (ratchet)
2019 - 148 (elevator bearing blocks)
Sketch of the Day
Goals have the intake behind the shooter and enough room to hold 5 balls. Intake would be able to bring two balls up on to our robot at a time, those two balls would then funnel into a single file line.
Spectrum
January 8, 20202020 Day 4 - Design Review 1
Design Review #1
On Tuesday's during the season we have our design reviews. We use a common google slide document to collect design ideas, and then also to present subsystem progress to the entire team.
Today's review was mostly going over all the notes people have taken on past robots and ideas for things to include in our robot. Here are a few slides from our notes.
Shooter Intake Locations
One of the biggest things we have been discussion is the pros and cons of the relationship between different Shooter & Intake locations and/or the need for a turret. We finished our design review by listing the pros and cons or each individual option and the pros and cons of each combination. There was a lot of debate and thought to how our robot would actually play the game,
Our current plan is to have the intake on one side of the robot and the shooter facing the opposite direction (Opposite - Separated) so we can easily acquire more balls in autonomous or from the feeder station and return to a shooting position without turning around. The feeder station may also be able to roll balls directly towards our intake.
Initial Subsystems List
We have a rough subsystem list of ideas we are currently pursuing. (robot will 45" tall)
1. Drive Train - 4x 6" Pneumatic - 2x Omni - 4 Falcon - Shifting (10.4fps - 19fps)
2. Climber - Extending drawer slides
3. Intake - Simple rollers over the bumper, limited to ~ 3 balls wide, funnels to 2 balls.
4. Ball Path - Smaller area funnels 2 balls into a single file belt tower up to the shooter
5. Shooter - Accelerator Wheel(s) and Shooter wheel with adjustable hood.
6. Buddy Forks- After we are hooked on, forks deploy under our robot that allow a <28" tall partner robot to drive under us and then we lift both of us higher into the air for both climbs.
7. Control Panel Spinner - Single NEO 550 in a VP or Ultraplanetary, driving two vertical rollers with a REV color sensor over the top of the wheel.
Robots That Inspired us Today
2010 - 469 (ball cycle)
2012 - 341 (Angled Bumpers, 3-2-1 Intake Path - Opposite Facing Intake/Shooter for Auton, Low CG), 987 (Narrow intake was able to be very effective)
2013 - 469 (full court or cycle)
Spectrum
January 8, 20202020 Day 5: "Sweet Spot" Parabola
Trajectory Calculators and the "Sweet Spot" Parabola
For those of you that weren't involved in FRC back in 2014, you may not be aware that Aren Hill, a friend of Spectrum, "invented parabolas." During VEX's Build Blitz that season Aren detailed a method of deciding on your shot trajectory by defining a wide "sweet spot". The same principle should work this year.
During tonight's meeting we did some analysis using two tools published on chiefdelphi to calculate the trajectory of the ball from a shooter. Thanks to CMarley, and Sam Geckler for posting these calculators.
The goal is to find a trajectory to limit the amount of variations you need in your shooting mechanism, while maximizing the distance range from goal for which you can still put the ball in the goal.
Basic idea, have the top of your arc at the top of the goal and a long flat tail on each side of the apex that still allows your ball to go into the goal.
Here are a few of the graphs we made tonight.
A wide range of distance that make it in the outer goal.
A similar shot in the other calculator
A shot that focuses more on the inner 3pt goal
If you can tune your shooter to fire every ball at a similar trajectory you may not need to adjust your velocity or angle as much as you think.
Robots That Inspired Us Today
2013 - 1114 (Dingus), 118 (Frisbee Angle Deflector)
2016 - 2056 (Simple adjustable rigid hood)
2017 - 33 (shooter/feeder), 1986 (Single Big Shooter Wheel)
2018 - 2877 (vision)
2019 - 148 (Climber Legs)
January 9, 20202020 Day 6: Advancing the complete idea
Robot Design Plan Updates
A little more thought, some more white board drawings and conversations, and a few bench tests have led us to a few design changes for our prototypes.
1. Shooter - reduce some complexity with fewer rollers and feed wheels than planed. Shooter and tower moved towards the front of the robot, to allow a much easier ball path while keep the intake behind it.
2. Shooter Hood - Two positions, a long wide shot that will make a ball into the 2 pt goal from behind mid court and up to the initiation line and a shallower angle that is specialized for 3 pt goal from a smaller range on the field. We are currently choosing to not shoot from the target zone.
3. Shooter Tower - Stop balls from entering the shooter by decompressing the top of the tower by moving one of the belts away from the ball.
4. Climber - doesn't need to be directly over our CG it's okay if we curl a little while we solo climb as long as our climber is rigid. Climber has also moved to a standard single stage 2x1 elevator as it now longer needs to stay below our shooter path as the shooter is turned around on our robot.
5. Buddy Climb - The buddy climb forks are now powered down instead of being sprung down. We believe this will let us make it easier to keep the forks on the floor even if our CG isn't directly under the hooks.
Drive Train Update
CAD has been underway on our drive train since Sunday. There is still work to do but it's coming along nice. We have had issues with a large sheet metal front rail on multiple instances so this year we are planning to combine sheet metal drive rails with an extrusion cross bar that are put into compression with threaded rod and some 3D printed inserts on the side of the tube ends..
Robots that inspired us today
2013 - 610 (drive construction)
2019 - 148 (elevator & climbing legs), 971 (climbing legs and bumper mounting)
Sketch of the Day
Spectrum
January 11, 2020Day 7: Making a few shots and a lot of misses.
Shooter Testing
We modified the shooter from our 2017 robot to be able to launch power cells. It's mounted to our protocube (just a cube made of 2x4s but we find lots of uses for it).
In 2017 it was one 775pro geared 4:1, it's now 2x 775pros geared 2:1. The hood has 1/8" rubber sheet to ensure the ball is rolling and doesn't slip on the polycarbonate panel. This shooter was based on the FRC#33 2017 shooter when be built it that season.
It shoots with 4 solid Fairlane nitrile rollers (RR-754-35W-RP). It also has been setup with two smaller diameter accelerator motors to attempt to have the effects of hand feeding the ball some what mitigated.
We are running it currently without velocity control, we have a small tachometer and it shows that the wheels are spinning at 5700 RPM at full voltage. This shows that the 775pros motors are having trouble getting the wheels anywhere near their free speed.
Video of some of the initial test can be seen on our photo gallery
This shot was about 25ft.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-F8H8wNg/A
The compression at the tightest was around 2.5" (4.5" from wheel to hood).
Part of goal is to see how we can make consistent shots with a variety of balls. We will continue to play with this shooter setup tomorrow to see how we can improve consistency.
Our next prototype will be moving up to a 6" wheel to get it closer to the correct RPM range for the free speed of NEOs at 1:1 or slightly over driven.
3D Printing Prototype Parts
All this week we have been printing parts for prototypes.
Today we started making some larger parts. Wheel extension on the left, intake ramps on the left.
We have use countless Protopipe parts as well we printed up a bunch of HYPEblocks for the next iteration of our shooter prototype.
Robots that inspired us today
2017 - 33 (shooter)
2019 - 148 (elevator chain attachment)
WCP - Greyt Elevator V2
Sketch of the Day
Figuring out some of our climber geometry
Spectrum
January 12, 20202020 Day 8: Quick Update
Power Cell Shooter Testing
Quick shooter testing video from today, we are now starting to believe we can make a more consistent shooter. Our plan is to have a wide 6" wheel and concentric flat hood. That will be were are next shooter starts.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-ptLfBsS/A
Block CAD of the Robot
As subsystems start figuring out how much room they need we star laying things out in quick block sketches to make sure we won't have systems needing the same space and see how we can leverage nearby subsystem together.
This is all very rough and almost none of this other than the drive train will actually be on our robot. It's also missing an intake at the moment as we are still figuring out exactly what that will look like.
Spectrum
January 14, 20202020 Day 9 & 10
Everybot and Week 6 Robots
This past Sunday, Spectrum was able to attend an event hosted by the Robonauts were Everybot and Week 6 demonstrated game play together. Both robots were very well done for only needing one week to complete.
Takeaways (Some are just confirmations of what we already knew)
- The outer goal is very large. Week 6 was able to easily manually aim their robot to score consistent shots.
- Fast low bots may have value in getting up to the RP level of balls but you need to be very quick in getting balls dumped into the goal and quick at intaking balls. Everybot does both very well.
- The balance even on the wooden switch didn't seem hard to accomplish. A reliable and consistent climb will be incredibly important.
- Driving across the Dance Floor (rendezvous points) will test how robustly made a lot of robots are. Make sure you test your robot driving over 1" bumps (the kit 2x1 is a good approximation) before coming to your first event. We are going to see a lot of radios, roboRIOs, batteries and other electronics and connectors come loose if they are only zip tied loosely to robots.
More photos and videos are in our photo gallery.
Shooter Prototype V2
Hopefully will have test shots tomorrow after we make it a little more rigid.
Intake/Indexing
Intake and indexing plans are still up in the air. We are re-investigating an intake similar to 971's from 2012. At first we didn't think it would package nicely but after some other changes to the design we think we can make it fit, but we need to build a better model to make sure it will index the balls fast enough for our robot.
Robots that inspired us today
2012 - 971 (intake & ball funneling), 2056 (ball funneling)
2013 - 180 (shooting game objects inside of your robot)
2017 - 125 ( 4-bar intake)
Spectrum
January 15, 20202020 Day 11: Design Review Week 2
Tuesday = design review day
Here are some of the slides from today's review put together by each of the subsystem lead groups.
Photo of V2 Prototype using HYPEblocks, hopefully we will have some testing tomorrow. We have to refactor the hood a bit.
Spectrum
January 16, 20202020 Day 12: New intake/indexer Plan
Block Robot Update
The new intake plan, allows for balls to rapidly be brought into the robot with a wide intake, and set quickly into the tower using a powered V similar to prototype videos from FRC#6135, FRC#4481 and FRC#95 . We plan to prototype some variations of this idea by adding a central channel for balls to rolls straight down and possibly a powered belt to move balls towards the tower belting as well. We will test various options for the side conveyors/wheels and also speeds and direction changes.
The tray on top of the intake is designed so this robot would be able to load from the human player station with the intake down. That should allow us to intake balls on the ground and then quickly get any remaining needed balls from the loading bay when drive in.
When retracted the intake acts as a cage around any balls remaining in the funnel to not allow them to bounce out of the robot as we drive over the boundaries.
We have prototypes of these systems under constructed and will post video and photos when they are operational.
Spectrum
January 16, 20202020 Day 13: Prototypes are working
Shooter
The shooter prototype was updated with a more rigid hood and basic velocity control on the NEO motors. It's shooting with 2 NEOs powering a 6" wheel 1:1 at 5000 RPM and a 4in accelerator wheel powered by 1 NEO 1:1 at 5000RPM. We plan to update the shooter to gear the main flywheel up so the NEOs have more power head room to maintain an RPM of around 5000. We also may test powering the accelerator wheel off the same two NEOs that are powering the main fly wheel.
Video
Intake
Our newest intake prototype is meeting all our expectations for an intake. The balls are rapidly moved up into our robot and our new indexer should be able to sort out the 3 wide balls pretty easily in the unlikely case we are intake 3 balls all sitting next to each other.
Video
Indexer
The indexer prototype based on FRC#6135 is working flawlessly.
Video of it working without intake
Video
More Pictures and Video of all the systems are available in our photo gallery.
Spectrum Dead Axle Rollers
The roller setup we have been using in our prototypes are based on a system we developed for our 2019 Cargo intake. We plan to use it again for our Power Cell intake.
The system has 6 parts
- 7/8" Aluminum Tubing
- 1.125" ID x 1.25" OD Polycarbonate Tubing
- McMaster Tube Connecting Nuts for 7/8" Tube
- 7/8" ID x 1.125" OD Needle Bearings
- 7/8" Push on Retaining Rings
- 3D printed Clamp-On Pulleys
- The 7/8" tube has the tube connecting nuts (star nuts) pressed into the ends of the length you need to span and is bolted into place on the ends acting as a standoff between two plates.
- The needle bearings go in the ends of the polycarbonate tube after you cut it to length.
- The push on retaining rings hold the tube and needle bearings in place.
- The 3D printed pulley clamps over the polycarbonate tube so it can be driven by a belt.
- Any rubber tube of your choice can be applied to the outside of the polycarbonate tube to provide grip on the game pieces.
Spectrum
January 18, 20202020 Day 14: Controls and Everybot
Controls Update
Our controls Subteam has been working on several projects already this year.
Their todo list is pretty long
- Path Following using BobTrajectory and HelixFollower
- PID tuning using the WPILib 2020 implementation
- Cameras
- Limelight target tracking
- Other software target and object tracking
- Driver camera streaming
- Control Panel Color Sensing and automation
- Ball indexing
- Scouting and Data Visualization
- Automated Subsystem Testing (based on 254 sample code)
- Improving Camera Stream Viewing
Over the past few days we have been testing OpenSight and learning to implement a simple power cell tracker.
Everybot Project
Several of our newer team members are working on building a version of the Everybot The Everybot is the model for teams with limited resources to design an effective robot. Every year there are teams that follow the Everybot documentation that have very successful seasons. Spectrum is building an Everybot so we can have a robot to practice with and we will also release any updates that we make to our version.
The kit drive base construction got under way this week.
Spectrum
January 19, 20202020 Day 15: Some progress
Shooter Hood
Tomorrow we will be testing some new shooter hood additions. We have yoga mat foam and PTFE sheet mounted to the hood.
Belt Tower Testing
We built a belt tower testing rig out of prototype so we can see how the balls react to each other and try to learn to prevent jamming mechanically in addition to control solutions that will come later.
Controls
Opensight was setup today to stream two driver cameras to the driver station and was using less than 3Mbps to do so. The controls team also looked into some edge detection as well.
Spectrum
January 20, 20202020 Day 16: Drive Gearboxes and Shooter Testing
Shooter Testing
We did more shooter testing today. We made several changes all at once we normally try not to do but circumstances were somewhat beyond our control. The modified VEX traction tire we had been shooting with had a failure and one of the tires broke apart. We won't be using that wheel anymore for our development of competition. It's possible it was just our implementation but we will be going with a solid wheel from here on out. We moved to 2x 6x1.5" colsons wheels we had from our 2015 drive train.
We also changed the gearing to move the NEOs to 1:1.5 with a 36 tooth pulley on the NEO output and a 24t on the shooter wheel. We did some tests with the accelerator wheel on it's own NEO and then moved to a setup that had the 4" accelerator wheel ganged together with the colson shooter wheels 1:1 and only shot using 2 NEOs. The smaller diameter means that the 4" wheel will have a reduced surface speed.
We also tested our shooter with a new backing of yoga mat foam and Teflon sheet. This backing still couldn't let us nicely shoot ball #14 (a ball that has previously been sliced open multiple times in a belt prototype). Once the balls have enough cuts, rips, tares, and holes to vent at a similar rate to a new ball they become very hard to shoot.
Here is one of our tests. The one ball that lands short is the ball that has multiple cuts through the skin. It compresses far easier than the other balls and the yoga foam doesn't seem to help.
After we adjusted the angle we were able to start hitting the 3 point inner goal from approximately the initiation line.
Drive Gearbox
The test fit of our drive gearboxes was done today. The competition versions will be 1/4" Aluminum plate but we can make sure everything working out of delrin or polycarbonate on our laser cutter. We are using a gearbox design inspired from this thread by Evan Morrison. Our implementation isn't direct drive so we can simplify some things as we don't need as much reduction. The 32:12 chain reduction to the wheels will get us a large part of each gears overall reduction. The spacers are 7/8" round tube with 3D printed inserts.
Block Robot Update
More of the design is starting to take shape.
Everybot Documentation is out
The awesome people behind Everybot have released this year's build guide and a brand new website. If your team is struggling to figure out what to build, building a robot based on the Everybot is a great idea. This robot will be effective in the 2020 FRC game for a large number of teams, definitely think about if your team should be one of them, it's a really good idea. Maybe you have another idea for a ball mechanism but just want to use their climbing mechanism, that works too. No matter what reading through their documentation will make you better at building robots and give you new ideas.
Spectrum
January 20, 20202020 Day 17: Public CAD Release
CAD Updates
Today we finally reached a point with multiple systems to create our top level Solidworks assembly and add in the subsystems.
There are still a few subsystems to add but we are now working with most of the subsystems in one place with them mated in space. None of the subsystems are complete but each of the sub-teams is working on getting closer to real models for every part.
Public STEP File
We have published a STEP file of our current progress on GrabCAD. Remember that none of this robot is actually built and much of it is still in development so we don't recommend anyone using this design directly but we happily encourage teams to take inspiration from our progress and make versions of your own based on our CAD.
STEP File Download
We plan to upload a new STEP about once a week through out the rest of the season. If you haven't seen it updated in a while feel free to message us and we will try to get a new one made when we can.
Spectrum
January 21, 20202020 Day 18: Design Review #3
Design Review #3
Third Tuesday of the season means it's our third design review.
Here are a few of the slides presented to the team by the subsystem leads today.
Controls Update
More work has been done of the ball tracking using OpenSight.
Spectrum
January 22, 2020FRC 2020 Youtube Channels and Vlogs
There are a large amount of teams that post vlogs and prototype videos to youtube that don’t get seen by many people unless they are looking for them.
Several members of Spectrum have collected a bunch of these channels but we’d love to have more.
Full Sheet: vlogs.spectrum3847.org Submit New Channels: https://forms.gle/VxkR9st95uvC58y16
Spectrum
January 23, 20202020 Day 20: CAD updates
Largely we have been getting more of our subsystem designs CADed.
Shooter Design
We are experimenting with adding a rear kicker wheel to the shooter setup. The idea being to have more linear acceleration into the shooter wheel and less spin. It would be powered off the front accelerator wheel using polycord in a figure 8.
We have learned to use Solidworks surfaces to allow us to CAD a curved shooter hood and then unwrap it so we can easily laser cut it from a flat piece of material.
Funnel
The Powered V funnel (based on FRC#6135’s design), is moving along. We will have custom printed pulleys on 7/8“ dead axles with 30mm wide, 5mm pitch timing belts to move the balls along. The BAG motors will be replaced by NEO550s in the real robot.
Climbing Brake
Last year we intended to use a VP ratchet slice to hold our robot after the match, but the standard ratchet slice never really worked. We ended up using a pneumatic cylinder driving into the ratchet adapter. We may be using a similar mechanism again this year.
Spectrum
January 24, 20202020 Day 21: First Sheet Metal Arrived & Everybot Tips
Sheet Metal Arrived
With stop build day no longer existing this year we decided to move to a slightly different model. In most seasons we would build our practice bot and competition bot about a week behind each other. When we would do a sheet metal order we would order enough for two+ robots. This year we are building a protobot, a competition robot, and a practice robot. The drive train sheet metal for the prototype robot arrived today. After the get the protobot working nicely and test fitted we will release the rest of the sheet order to our sponsor to build the competition and practice robots. The practice robot will be completed after the competition this season. The protobot will also be decommissioned to create the practice robot. This is to ensure that our practice and competition robots can be closer to identical.
We are also making a larger portion of our robot our of extrusion than we have done in the past few years.
Everybot Updates
Our Everybot project is moving along. We have the KOP chassis completed to the proper size and have begun cutting down some of the stock to make the Everybot.
We have found a cheaper source for the flex ratcheting wrench used on the Everybot climber. If you have a Grainger near you, you can order it and pick up in the store with no shipping charges.
https://www.grainger.com/product/WESTWARD-1-2-3LU37
We also have been using our bench shear and aviation snips to cut the tie plates into gussets instead of a band saw. We find this to be faster and easier.
Spectrum
January 25, 20202020 Day 22: Protobot Chassis & Purchases
Protobot Chassis
We found some issues with the current design that we will be fixing before we send off the comp bot and practice bot chassis.
Purchases
Here are some of the items 3847 has purchased this season from some non-FRC suppliers.
Belts from VBeltGuys.com
We started using them in 2018 and haven't looked back. Their timing belts are cheaper than every other source we have found and they have nearly every length and width you could want. Combined with 3D printed pulleys these have made there way on to many parts of our robots over the past few seasons.
A 70 tooth, 5mm pitch, 9mm wide HTD belt is 350-5M-09. The 350 is the belt circumference which is tooth count multiplied by pitch.
Vbeltguys.com
USB Wide Angle Camera
We have been using this camera for a couple seasons as well. The wide angle lets you see a much larger portion of the field while driving.
Amazon.com - ELP 170degree Fisheye Wide Angle VGA USB Camera
Cheap PTFE Sheet
This is way cheaper than the comparable product from McMaster and from our brief testing seems as slippery on the ball as the McMaster stuff. It's possible it's not pure PTFE but it's what we are planning to use on our robot.
Amazon.com PTFE Film No Adhesive, Pure White 16 x 60 inch
PLA Pro Filament
We have been using this filament extensively this season. It has all of the benefits of PLA, fast print speeds, stiffness, and inexpensive but it's far less brittle than normal PLA and stronger. There are still times for even stronger and tougher filaments but for general printing this is our new default material.
January 26, 20202020 Day 23: Intakes and Drive Trains
Falcon Pinions
We ran into our first issue with the Falcon 500s are second batch of pinions were a tight fit on the falcon shafts which is a known issue and is discussed in that thread. We used a wire wheel brush similar to ones in this kit. It took some of the nice black finish off the front of the falcon with it but it worked to take the shaft OD down enough to get a nice slip fit for pinions. We noticed that most of the pinions prefer to go on to the shafts a certain side first. When slipped on to the shaft the other direction they seem to stop sooner but when you turn them around they slip all the way down after the wire wheel.
Protobot Progress
Our protobot intake, indexer, and drive train are coming along.
Small incremental improvement are on the way, which is why we are doing it on a full prototype robot. So we can drive it and make changes for the comp robot to handle the balls better.
Spectrum
January 27, 20202020 Day 24: CAD Update & Vision Update
CAD Updated
The STEP file on GrabCAD has been updated for this week. You can download it here - https://grabcad.com/library/spectrum-3847-2020-ultraviolet-frc-robot-1
Vision Progress
We have made a lot of progress using opensight to be able to track balls and track the rectangle on the loading bay. We are planning to use a limelight for aiming our robot and to have two additional cameras for driver viewing and tracking of balls and the loading bay.
Ball tracking is using a color filter and then selecting only circles.
The rectangle tracking is just normal shape tracking on the retro-reflective tape.
Spectrum
January 28, 20202020 Day 25: Design Review #4
January 29, 20202020 Day 26: Intake progress and motor allocations
Intake Progress
Progress on the Protobot intake and funnel have come to their 2nd iteration.
This version fixes some geometry issues with the first and removes the belt path from the center of the funnel.
Motor Allocations
We added our motor allocations to our copy of the Spectrum Design Sheet (Designsheet.spectrum3847.org)
Updated Guide to the FRC MCC
We updated our guide to the FRC MCC with new resources and tips. We added example MCCs from the 2019 season. We have added a section on sensors and counterbalancing mechanisms. We also updated most of the links and added new vendors to the recommended purchases.
Updated Spectrum Design Sheet
We have added Falcon 500s and both NEOs and NEO 550s to the mechanical section. We have reorganized several of the pages based on how we used it during the 2019 season. We have improved the BOM section and added a parts organization sheet.
This sheet is how we organize our robot construction and helps us design mechanisms without having to re-lookup information over and over throughout the process.
FRC Maintenance Guide
This is the first year teams can do extensive maintenance and cleaning of their robots between events. Ideally, your robot should be squeaky clean and running at peak performance at the start of each event. We started working on a Maintenance guide to use internally but decided to make it public so that other teams could benefit as well.
The full manual can be found here - https://www.firstinspires.org/resource-library/frc/competition-manual-qa-system
X-Ray 2019 Robot and Code
Below are our CAD and Code for our 2019 Robot X-Ray
Notes/Research
These are two very rough documents. These are just research docs for two different things we were interested in during the off-season.- Large aluminum pneumatic storage tanks
- For robots that use a large amount of air, these ~2 gallon air tanks can be more weight-efficient than the plastic tanks teams often use.
- 6" Pneumatic Tires
- We wanted to find a 6" pneumatic tire that could be used in a dead axle drive setup. There a lot of great options, some of our notes are in this document.
Other Spectrum Resources
- Recommended Reading - This document is continually updated.
- Blog - Our 2020 Build Blog will begin tomorrow.
- Photo Gallery & Mechanism Library
- 2019 Resource Collection
- 2018 Resource Collection
- Spectrum
January 5, 2020
2020 Day 1: Rules and Inspiration
2020 Infinite Recharge
Below is the game animation for the 2020 FRC Game Infinite Recharge.
Rules
Most of our first day of build season was reading the rules for Infinite Recharge. We need everyone that is going to be helping design the robot to understand the game rules and the robot rules so they can help in that challenge.The full manual can be found here - https://www.firstinspires.org/resource-library/frc/competition-manual-qa-system
Humans Play Infinite Recharge
We often have our team play the game out as if they were robots. It's mostly just for fun and it reinforces some of the field locations and names of the field objects. We apologize for the audio, filmed quickly on a phone.
Robots that inspired us today
2006 Robots - 217
2012 Robots - 971, 341, 254, 33, 118
2016 Robots - 3476, 1241, 33 (hood)
2018 Robots - 118(forks), 148 (wrangler)
We were looking at various ball paths and intakes from 2012 & 2016 robots that we may be able to use ideas from this season. We were also looking at various ways to possibly lift a partner off the ground with our climb as well.
- low goal, human feed and simple floor intake through a bumper gap (over bumper is harder)
- hook flip out style climb that deploys and then you can winch up. Multiple robots in 2018 did this.
- no color wheel manipulation, it takes too many balls scored before this becomes valuable.
- Spectrum
If you are thinking about which tasks on the field to do, climbing is the most beneficial after only being able to drive successfully around the field and over the small barriers.
Robots that inspired us today
2006 Robots - 217
2012 Robots - 971, 341, 254, 33, 118
2016 Robots - 3476, 1241, 33 (hood)
2018 Robots - 118(forks), 148 (wrangler)
We were looking at various ball paths and intakes from 2012 & 2016 robots that we may be able to use ideas from this season. We were also looking at various ways to possibly lift a partner off the ground with our climb as well.
Basic MCC Discussion
Our initial MCC (Minimum Competitive Concept) thoughts,- low goal, human feed and simple floor intake through a bumper gap (over bumper is harder)
- hook flip out style climb that deploys and then you can winch up. Multiple robots in 2018 did this.
- no color wheel manipulation, it takes too many balls scored before this becomes valuable.
- Spectrum
January 6, 2020
2020 - Day 2
Climbing is incredibly valuable
If you are thinking about which tasks on the field to do, climbing is the most beneficial after only being able to drive successfully around the field and over the small barriers.
- At 25 points (20+ over just parking), it is worth ~7 balls in the inner goal or 20 balls in the low goal.
- It can happen very quickly at the end of the match, leaving you time to do other teams like score balls, feed balls, & play defense.
- It is points that only your robot can get. Your partners can pick up and score balls that you don't, they might be able to use the control panel to score points, but the 20+ points for you being off the ground requires you to be there.
- If you and one other person on, your alliance can climb and balance your alliance receives a ranking point.
The climb does not have to be difficult. This is the first time in some time where the only requirement for climb points is that your robot must be off the ground. (2013 was the last). If you are willing to be a tall robot, you can fold out an arm with a short (<8") pneumatic cylinder and use that to lift you 4"+ off the floor. There are also ways that you can climb be getting a hook on to the bar and using a winch to pull yourself. There are countless other options, but doing one of them successfully will make you much more likely to be picked for eliminations.
Control Panel Tasks are less valuable
In contrast to climbing, the control panel tasks are less valuable, and your team should strongly consider limiting the number of resources you devote to this task.
2012 Robots - 33 (linkage Hood, CD7 Intake, and J shooter path), 118 (intake only has grip in the middle)
2013 Robots - 1986 (Climber), 254 (climber)
2016 Robots - 195(scissor lift), 2056(climber)
2017 Robots - 971(rack hood), 33(accelerator rollers), 5803 (ball path)
2018 Robots - 33 (double reverse 4-bar), 125 & 1323(buddy climbs), 2056 (forks)
2019 Robots - 3940 (floating roller on intake)
If you're looking for some inspiration, here is a good place to see photos of some Aim High 2006 robots.
Pictures - http://www.firstrobotpics.com/?page_id=49
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-VQ2CwLV/A
Low CG and CG at the front of you robot handles the bumps better. Also this chassis has pneumatic tires.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-v9ftd6p/A
Intake Test
Protopipe has proved very useful for quickly making intake tests.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-CBtkmGp/A
Drawer Slide Elevator Test
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-SVGDst4/A
More videos and photos of these tests can be found on our photo gallery Photo.Spectrum3847.org - 2020 Build Season Gallery
2012 - 48, 341 (Photo Gallery), 548 & 330 (shooter on a pivot)
2013 - 33(Frisbee path), 987 (gas springs on climber), 1986 (climber)
2014 - 2590 (ratchet)
2017 - 319 (ratchet)
2019 - 148 (elevator bearing blocks)
- While there are a lot of points (35) associated with these tasks. Your alliance is required to score a lot of balls before these tasks ever become an option for you to get points. (29+ and 49+ balls) These ball counts will be rare in qualifications matches (and probably playoff matches as well) at many events around the world. You can be the best control panel robot in the world, but if you can't score enough balls to charge the 2nd and 3rd phase, you'll never be able to use your skill.
- Even if your alliance is able to score enough balls, only one member of each alliance is needed to complete the tasks. Strongly consider where that robot should be your team, or if this is a task, you can leave to another member of your alliance.
Building Field Elements
We have started building our field elements. Working to make sure we can interact with our team elements in similar ways that we will be able to interact with the real field.
Robots that inspired us today
2006 Robots - 111 (Rack & Pinion Hood)2012 Robots - 33 (linkage Hood, CD7 Intake, and J shooter path), 118 (intake only has grip in the middle)
2013 Robots - 1986 (Climber), 254 (climber)
2016 Robots - 195(scissor lift), 2056(climber)
2017 Robots - 971(rack hood), 33(accelerator rollers), 5803 (ball path)
2018 Robots - 33 (double reverse 4-bar), 125 & 1323(buddy climbs), 2056 (forks)
2019 Robots - 3940 (floating roller on intake)
If you're looking for some inspiration, here is a good place to see photos of some Aim High 2006 robots.
Pictures - http://www.firstrobotpics.com/?page_id=49
Sketch of the Day
A long robot (32-34") can store 5 balls in a line before entering a shooter.
- Spectrum
- Spectrum
January 6, 2020
2020 - Day 3 - Starting some tests
Today's Tests
Bump crossing tests - CG is important and braking hard is badhttps://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-VQ2CwLV/A
Low CG and CG at the front of you robot handles the bumps better. Also this chassis has pneumatic tires.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-v9ftd6p/A
Intake Test
Protopipe has proved very useful for quickly making intake tests.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-CBtkmGp/A
Drawer Slide Elevator Test
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-SVGDst4/A
More videos and photos of these tests can be found on our photo gallery Photo.Spectrum3847.org - 2020 Build Season Gallery
Robots that inspired us today
2009 - 67 (Multi ball shooter)2012 - 48, 341 (Photo Gallery), 548 & 330 (shooter on a pivot)
2013 - 33(Frisbee path), 987 (gas springs on climber), 1986 (climber)
2014 - 2590 (ratchet)
2017 - 319 (ratchet)
2019 - 148 (elevator bearing blocks)
Sketch of the Day
Goals have the intake behind the shooter and enough room to hold 5 balls. Intake would be able to bring two balls up on to our robot at a time, those two balls would then funnel into a single file line.
Today's review was mostly going over all the notes people have taken on past robots and ideas for things to include in our robot. Here are a few slides from our notes.
Spectrum
January 8, 2020
2020 Day 4 - Design Review 1
Design Review #1
On Tuesday's during the season we have our design reviews. We use a common google slide document to collect design ideas, and then also to present subsystem progress to the entire team.Today's review was mostly going over all the notes people have taken on past robots and ideas for things to include in our robot. Here are a few slides from our notes.
Shooter Intake Locations
One of the biggest things we have been discussion is the pros and cons of the relationship between different Shooter & Intake locations and/or the need for a turret. We finished our design review by listing the pros and cons or each individual option and the pros and cons of each combination. There was a lot of debate and thought to how our robot would actually play the game,
Our current plan is to have the intake on one side of the robot and the shooter facing the opposite direction (Opposite - Separated) so we can easily acquire more balls in autonomous or from the feeder station and return to a shooting position without turning around. The feeder station may also be able to roll balls directly towards our intake.
1. Drive Train - 4x 6" Pneumatic - 2x Omni - 4 Falcon - Shifting (10.4fps - 19fps)
2. Climber - Extending drawer slides
3. Intake - Simple rollers over the bumper, limited to ~ 3 balls wide, funnels to 2 balls.
4. Ball Path - Smaller area funnels 2 balls into a single file belt tower up to the shooter
5. Shooter - Accelerator Wheel(s) and Shooter wheel with adjustable hood.
6. Buddy Forks- After we are hooked on, forks deploy under our robot that allow a <28" tall partner robot to drive under us and then we lift both of us higher into the air for both climbs.
7. Control Panel Spinner - Single NEO 550 in a VP or Ultraplanetary, driving two vertical rollers with a REV color sensor over the top of the wheel.
2012 - 341 (Angled Bumpers, 3-2-1 Intake Path - Opposite Facing Intake/Shooter for Auton, Low CG), 987 (Narrow intake was able to be very effective)
2013 - 469 (full court or cycle)
Spectrum
During tonight's meeting we did some analysis using two tools published on chiefdelphi to calculate the trajectory of the ball from a shooter. Thanks to CMarley, and Sam Geckler for posting these calculators.
Our current plan is to have the intake on one side of the robot and the shooter facing the opposite direction (Opposite - Separated) so we can easily acquire more balls in autonomous or from the feeder station and return to a shooting position without turning around. The feeder station may also be able to roll balls directly towards our intake.
Initial Subsystems List
We have a rough subsystem list of ideas we are currently pursuing. (robot will 45" tall)1. Drive Train - 4x 6" Pneumatic - 2x Omni - 4 Falcon - Shifting (10.4fps - 19fps)
2. Climber - Extending drawer slides
3. Intake - Simple rollers over the bumper, limited to ~ 3 balls wide, funnels to 2 balls.
4. Ball Path - Smaller area funnels 2 balls into a single file belt tower up to the shooter
5. Shooter - Accelerator Wheel(s) and Shooter wheel with adjustable hood.
6. Buddy Forks- After we are hooked on, forks deploy under our robot that allow a <28" tall partner robot to drive under us and then we lift both of us higher into the air for both climbs.
7. Control Panel Spinner - Single NEO 550 in a VP or Ultraplanetary, driving two vertical rollers with a REV color sensor over the top of the wheel.
Robots That Inspired us Today
2010 - 469 (ball cycle)2012 - 341 (Angled Bumpers, 3-2-1 Intake Path - Opposite Facing Intake/Shooter for Auton, Low CG), 987 (Narrow intake was able to be very effective)
2013 - 469 (full court or cycle)
Spectrum
January 8, 2020
2020 Day 5: "Sweet Spot" Parabola
Trajectory Calculators and the "Sweet Spot" Parabola
For those of you that weren't involved in FRC back in 2014, you may not be aware that Aren Hill, a friend of Spectrum, "invented parabolas." During VEX's Build Blitz that season Aren detailed a method of deciding on your shot trajectory by defining a wide "sweet spot". The same principle should work this year.During tonight's meeting we did some analysis using two tools published on chiefdelphi to calculate the trajectory of the ball from a shooter. Thanks to CMarley, and Sam Geckler for posting these calculators.
The goal is to find a trajectory to limit the amount of variations you need in your shooting mechanism, while maximizing the distance range from goal for which you can still put the ball in the goal.
Basic idea, have the top of your arc at the top of the goal and a long flat tail on each side of the apex that still allows your ball to go into the goal.
Basic idea, have the top of your arc at the top of the goal and a long flat tail on each side of the apex that still allows your ball to go into the goal.
Here are a few of the graphs we made tonight.
A wide range of distance that make it in the outer goal.
A similar shot in the other calculator
A shot that focuses more on the inner 3pt goal
If you can tune your shooter to fire every ball at a similar trajectory you may not need to adjust your velocity or angle as much as you think.
2016 - 2056 (Simple adjustable rigid hood)
2017 - 33 (shooter/feeder), 1986 (Single Big Shooter Wheel)
2018 - 2877 (vision)
2019 - 148 (Climber Legs)
Robots That Inspired Us Today
2013 - 1114 (Dingus), 118 (Frisbee Angle Deflector)2016 - 2056 (Simple adjustable rigid hood)
2017 - 33 (shooter/feeder), 1986 (Single Big Shooter Wheel)
2018 - 2877 (vision)
2019 - 148 (Climber Legs)
January 9, 2020
2020 Day 6: Advancing the complete idea
Robot Design Plan Updates
A little more thought, some more white board drawings and conversations, and a few bench tests have led us to a few design changes for our prototypes.
1. Shooter - reduce some complexity with fewer rollers and feed wheels than planed. Shooter and tower moved towards the front of the robot, to allow a much easier ball path while keep the intake behind it.
2. Shooter Hood - Two positions, a long wide shot that will make a ball into the 2 pt goal from behind mid court and up to the initiation line and a shallower angle that is specialized for 3 pt goal from a smaller range on the field. We are currently choosing to not shoot from the target zone.
3. Shooter Tower - Stop balls from entering the shooter by decompressing the top of the tower by moving one of the belts away from the ball.
4. Climber - doesn't need to be directly over our CG it's okay if we curl a little while we solo climb as long as our climber is rigid. Climber has also moved to a standard single stage 2x1 elevator as it now longer needs to stay below our shooter path as the shooter is turned around on our robot.
5. Buddy Climb - The buddy climb forks are now powered down instead of being sprung down. We believe this will let us make it easier to keep the forks on the floor even if our CG isn't directly under the hooks.
Drive Train Update
CAD has been underway on our drive train since Sunday. There is still work to do but it's coming along nice. We have had issues with a large sheet metal front rail on multiple instances so this year we are planning to combine sheet metal drive rails with an extrusion cross bar that are put into compression with threaded rod and some 3D printed inserts on the side of the tube ends..
2019 - 148 (elevator & climbing legs), 971 (climbing legs and bumper mounting)
Robots that inspired us today
2013 - 610 (drive construction)2019 - 148 (elevator & climbing legs), 971 (climbing legs and bumper mounting)
Sketch of the Day
Spectrum
January 11, 2020
Day 7: Making a few shots and a lot of misses.
Shooter Testing
We modified the shooter from our 2017 robot to be able to launch power cells. It's mounted to our protocube (just a cube made of 2x4s but we find lots of uses for it).
In 2017 it was one 775pro geared 4:1, it's now 2x 775pros geared 2:1. The hood has 1/8" rubber sheet to ensure the ball is rolling and doesn't slip on the polycarbonate panel. This shooter was based on the FRC#33 2017 shooter when be built it that season.
It shoots with 4 solid Fairlane nitrile rollers (RR-754-35W-RP). It also has been setup with two smaller diameter accelerator motors to attempt to have the effects of hand feeding the ball some what mitigated.
It shoots with 4 solid Fairlane nitrile rollers (RR-754-35W-RP). It also has been setup with two smaller diameter accelerator motors to attempt to have the effects of hand feeding the ball some what mitigated.
We are running it currently without velocity control, we have a small tachometer and it shows that the wheels are spinning at 5700 RPM at full voltage. This shows that the 775pros motors are having trouble getting the wheels anywhere near their free speed.
Video of some of the initial test can be seen on our photo gallery
This shot was about 25ft.
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-F8H8wNg/A
The compression at the tightest was around 2.5" (4.5" from wheel to hood).
Part of goal is to see how we can make consistent shots with a variety of balls. We will continue to play with this shooter setup tomorrow to see how we can improve consistency.
Our next prototype will be moving up to a 6" wheel to get it closer to the correct RPM range for the free speed of NEOs at 1:1 or slightly over driven.
3D Printing Prototype Parts
All this week we have been printing parts for prototypes.
Today we started making some larger parts. Wheel extension on the left, intake ramps on the left.
We have use countless Protopipe parts as well we printed up a bunch of HYPEblocks for the next iteration of our shooter prototype.
Robots that inspired us today
2017 - 33 (shooter)
2019 - 148 (elevator chain attachment)
2019 - 148 (elevator chain attachment)
WCP - Greyt Elevator V2
Sketch of the Day
Figuring out some of our climber geometry
https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-ptLfBsS/A
Spectrum
January 12, 2020
2020 Day 8: Quick Update
Power Cell Shooter Testing
Quick shooter testing video from today, we are now starting to believe we can make a more consistent shooter. Our plan is to have a wide 6" wheel and concentric flat hood. That will be were are next shooter starts.https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-ptLfBsS/A
Block CAD of the Robot
As subsystems start figuring out how much room they need we star laying things out in quick block sketches to make sure we won't have systems needing the same space and see how we can leverage nearby subsystem together.
This is all very rough and almost none of this other than the drive train will actually be on our robot. It's also missing an intake at the moment as we are still figuring out exactly what that will look like.
Spectrum
January 14, 2020
2020 Day 9 & 10
Everybot and Week 6 Robots
This past Sunday, Spectrum was able to attend an event hosted by the Robonauts were Everybot and Week 6 demonstrated game play together. Both robots were very well done for only needing one week to complete.
Takeaways (Some are just confirmations of what we already knew)
More photos and videos are in our photo gallery.
- The outer goal is very large. Week 6 was able to easily manually aim their robot to score consistent shots.
- Fast low bots may have value in getting up to the RP level of balls but you need to be very quick in getting balls dumped into the goal and quick at intaking balls. Everybot does both very well.
- The balance even on the wooden switch didn't seem hard to accomplish. A reliable and consistent climb will be incredibly important.
- Driving across the Dance Floor (rendezvous points) will test how robustly made a lot of robots are. Make sure you test your robot driving over 1" bumps (the kit 2x1 is a good approximation) before coming to your first event. We are going to see a lot of radios, roboRIOs, batteries and other electronics and connectors come loose if they are only zip tied loosely to robots.
More photos and videos are in our photo gallery.
Shooter Prototype V2
Hopefully will have test shots tomorrow after we make it a little more rigid.
2013 - 180 (shooting game objects inside of your robot)
2017 - 125 ( 4-bar intake)
Photo of V2 Prototype using HYPEblocks, hopefully we will have some testing tomorrow. We have to refactor the hood a bit.
Spectrum
Intake/Indexing
Intake and indexing plans are still up in the air. We are re-investigating an intake similar to 971's from 2012. At first we didn't think it would package nicely but after some other changes to the design we think we can make it fit, but we need to build a better model to make sure it will index the balls fast enough for our robot.Robots that inspired us today
2012 - 971 (intake & ball funneling), 2056 (ball funneling)2013 - 180 (shooting game objects inside of your robot)
2017 - 125 ( 4-bar intake)
Spectrum
January 15, 2020
2020 Day 11: Design Review Week 2
Tuesday = design review day
Here are some of the slides from today's review put together by each of the subsystem lead groups.Photo of V2 Prototype using HYPEblocks, hopefully we will have some testing tomorrow. We have to refactor the hood a bit.
Spectrum
January 16, 2020
2020 Day 12: New intake/indexer Plan
Block Robot Update
The new intake plan, allows for balls to rapidly be brought into the robot with a wide intake, and set quickly into the tower using a powered V similar to prototype videos from FRC#6135, FRC#4481 and FRC#95 . We plan to prototype some variations of this idea by adding a central channel for balls to rolls straight down and possibly a powered belt to move balls towards the tower belting as well. We will test various options for the side conveyors/wheels and also speeds and direction changes.
The tray on top of the intake is designed so this robot would be able to load from the human player station with the intake down. That should allow us to intake balls on the ground and then quickly get any remaining needed balls from the loading bay when drive in.
When retracted the intake acts as a cage around any balls remaining in the funnel to not allow them to bounce out of the robot as we drive over the boundaries.
We have prototypes of these systems under constructed and will post video and photos when they are operational.
Spectrum
When retracted the intake acts as a cage around any balls remaining in the funnel to not allow them to bounce out of the robot as we drive over the boundaries.
We have prototypes of these systems under constructed and will post video and photos when they are operational.
Spectrum
January 16, 2020
2020 Day 13: Prototypes are working
Shooter
The shooter prototype was updated with a more rigid hood and basic velocity control on the NEO motors. It's shooting with 2 NEOs powering a 6" wheel 1:1 at 5000 RPM and a 4in accelerator wheel powered by 1 NEO 1:1 at 5000RPM. We plan to update the shooter to gear the main flywheel up so the NEOs have more power head room to maintain an RPM of around 5000. We also may test powering the accelerator wheel off the same two NEOs that are powering the main fly wheel.
Video
Intake
Our newest intake prototype is meeting all our expectations for an intake. The balls are rapidly moved up into our robot and our new indexer should be able to sort out the 3 wide balls pretty easily in the unlikely case we are intake 3 balls all sitting next to each other.
Video
Indexer
The indexer prototype based on FRC#6135 is working flawlessly.
Video of it working without intake
Video
More Pictures and Video of all the systems are available in our photo gallery.
Spectrum Dead Axle Rollers
The roller setup we have been using in our prototypes are based on a system we developed for our 2019 Cargo intake. We plan to use it again for our Power Cell intake.
The system has 6 parts
- 7/8" Aluminum Tubing
- 1.125" ID x 1.25" OD Polycarbonate Tubing
- McMaster Tube Connecting Nuts for 7/8" Tube
- 7/8" ID x 1.125" OD Needle Bearings
- 7/8" Push on Retaining Rings
- 3D printed Clamp-On Pulleys
- The 7/8" tube has the tube connecting nuts (star nuts) pressed into the ends of the length you need to span and is bolted into place on the ends acting as a standoff between two plates.
- The needle bearings go in the ends of the polycarbonate tube after you cut it to length.
- The push on retaining rings hold the tube and needle bearings in place.
- The 3D printed pulley clamps over the polycarbonate tube so it can be driven by a belt.
- Any rubber tube of your choice can be applied to the outside of the polycarbonate tube to provide grip on the game pieces.
Spectrum
January 18, 20202020 Day 14: Controls and Everybot
Controls Update
Our controls Subteam has been working on several projects already this year.
Their todo list is pretty long
- Path Following using BobTrajectory and HelixFollower
- PID tuning using the WPILib 2020 implementation
- Cameras
- Limelight target tracking
- Other software target and object tracking
- Driver camera streaming
- Control Panel Color Sensing and automation
- Ball indexing
- Scouting and Data Visualization
- Automated Subsystem Testing (based on 254 sample code)
- Improving Camera Stream Viewing
Over the past few days we have been testing OpenSight and learning to implement a simple power cell tracker.
Everybot Project
Several of our newer team members are working on building a version of the Everybot The Everybot is the model for teams with limited resources to design an effective robot. Every year there are teams that follow the Everybot documentation that have very successful seasons. Spectrum is building an Everybot so we can have a robot to practice with and we will also release any updates that we make to our version.
The kit drive base construction got under way this week.
Spectrum
January 19, 20202020 Day 15: Some progress
Shooter Hood
Tomorrow we will be testing some new shooter hood additions. We have yoga mat foam and PTFE sheet mounted to the hood.
Belt Tower Testing
We built a belt tower testing rig out of prototype so we can see how the balls react to each other and try to learn to prevent jamming mechanically in addition to control solutions that will come later.
Controls
Opensight was setup today to stream two driver cameras to the driver station and was using less than 3Mbps to do so. The controls team also looked into some edge detection as well.
Spectrum
January 20, 20202020 Day 16: Drive Gearboxes and Shooter Testing
Shooter Testing
We did more shooter testing today. We made several changes all at once we normally try not to do but circumstances were somewhat beyond our control. The modified VEX traction tire we had been shooting with had a failure and one of the tires broke apart. We won't be using that wheel anymore for our development of competition. It's possible it was just our implementation but we will be going with a solid wheel from here on out. We moved to 2x 6x1.5" colsons wheels we had from our 2015 drive train.
We also changed the gearing to move the NEOs to 1:1.5 with a 36 tooth pulley on the NEO output and a 24t on the shooter wheel. We did some tests with the accelerator wheel on it's own NEO and then moved to a setup that had the 4" accelerator wheel ganged together with the colson shooter wheels 1:1 and only shot using 2 NEOs. The smaller diameter means that the 4" wheel will have a reduced surface speed.
We also tested our shooter with a new backing of yoga mat foam and Teflon sheet. This backing still couldn't let us nicely shoot ball #14 (a ball that has previously been sliced open multiple times in a belt prototype). Once the balls have enough cuts, rips, tares, and holes to vent at a similar rate to a new ball they become very hard to shoot.
Here is one of our tests. The one ball that lands short is the ball that has multiple cuts through the skin. It compresses far easier than the other balls and the yoga foam doesn't seem to help.
After we adjusted the angle we were able to start hitting the 3 point inner goal from approximately the initiation line.
Drive Gearbox
The test fit of our drive gearboxes was done today. The competition versions will be 1/4" Aluminum plate but we can make sure everything working out of delrin or polycarbonate on our laser cutter. We are using a gearbox design inspired from this thread by Evan Morrison. Our implementation isn't direct drive so we can simplify some things as we don't need as much reduction. The 32:12 chain reduction to the wheels will get us a large part of each gears overall reduction. The spacers are 7/8" round tube with 3D printed inserts.
Block Robot Update
More of the design is starting to take shape.
Everybot Documentation is out
The awesome people behind Everybot have released this year's build guide and a brand new website. If your team is struggling to figure out what to build, building a robot based on the Everybot is a great idea. This robot will be effective in the 2020 FRC game for a large number of teams, definitely think about if your team should be one of them, it's a really good idea. Maybe you have another idea for a ball mechanism but just want to use their climbing mechanism, that works too. No matter what reading through their documentation will make you better at building robots and give you new ideas.
Spectrum
January 20, 20202020 Day 17: Public CAD Release
CAD Updates
Today we finally reached a point with multiple systems to create our top level Solidworks assembly and add in the subsystems.
There are still a few subsystems to add but we are now working with most of the subsystems in one place with them mated in space. None of the subsystems are complete but each of the sub-teams is working on getting closer to real models for every part.
Public STEP File
We have published a STEP file of our current progress on GrabCAD. Remember that none of this robot is actually built and much of it is still in development so we don't recommend anyone using this design directly but we happily encourage teams to take inspiration from our progress and make versions of your own based on our CAD.
STEP File Download
We plan to upload a new STEP about once a week through out the rest of the season. If you haven't seen it updated in a while feel free to message us and we will try to get a new one made when we can.
Spectrum
January 21, 20202020 Day 18: Design Review #3
Design Review #3
Third Tuesday of the season means it's our third design review.
Here are a few of the slides presented to the team by the subsystem leads today.
Controls Update
More work has been done of the ball tracking using OpenSight.
Spectrum
January 22, 2020FRC 2020 Youtube Channels and Vlogs
There are a large amount of teams that post vlogs and prototype videos to youtube that don’t get seen by many people unless they are looking for them.
Several members of Spectrum have collected a bunch of these channels but we’d love to have more.
Full Sheet: vlogs.spectrum3847.org Submit New Channels: https://forms.gle/VxkR9st95uvC58y16
Spectrum
January 23, 20202020 Day 20: CAD updates
Largely we have been getting more of our subsystem designs CADed.
Shooter Design
We are experimenting with adding a rear kicker wheel to the shooter setup. The idea being to have more linear acceleration into the shooter wheel and less spin. It would be powered off the front accelerator wheel using polycord in a figure 8.
We have learned to use Solidworks surfaces to allow us to CAD a curved shooter hood and then unwrap it so we can easily laser cut it from a flat piece of material.
Funnel
The Powered V funnel (based on FRC#6135’s design), is moving along. We will have custom printed pulleys on 7/8“ dead axles with 30mm wide, 5mm pitch timing belts to move the balls along. The BAG motors will be replaced by NEO550s in the real robot.
Climbing Brake
Last year we intended to use a VP ratchet slice to hold our robot after the match, but the standard ratchet slice never really worked. We ended up using a pneumatic cylinder driving into the ratchet adapter. We may be using a similar mechanism again this year.
Spectrum
January 24, 20202020 Day 21: First Sheet Metal Arrived & Everybot Tips
Sheet Metal Arrived
With stop build day no longer existing this year we decided to move to a slightly different model. In most seasons we would build our practice bot and competition bot about a week behind each other. When we would do a sheet metal order we would order enough for two+ robots. This year we are building a protobot, a competition robot, and a practice robot. The drive train sheet metal for the prototype robot arrived today. After the get the protobot working nicely and test fitted we will release the rest of the sheet order to our sponsor to build the competition and practice robots. The practice robot will be completed after the competition this season. The protobot will also be decommissioned to create the practice robot. This is to ensure that our practice and competition robots can be closer to identical.
We are also making a larger portion of our robot our of extrusion than we have done in the past few years.
Everybot Updates
Our Everybot project is moving along. We have the KOP chassis completed to the proper size and have begun cutting down some of the stock to make the Everybot.
We have found a cheaper source for the flex ratcheting wrench used on the Everybot climber. If you have a Grainger near you, you can order it and pick up in the store with no shipping charges.
https://www.grainger.com/product/WESTWARD-1-2-3LU37
We also have been using our bench shear and aviation snips to cut the tie plates into gussets instead of a band saw. We find this to be faster and easier.
Spectrum
January 25, 20202020 Day 22: Protobot Chassis & Purchases
Protobot Chassis
We found some issues with the current design that we will be fixing before we send off the comp bot and practice bot chassis.
Purchases
Here are some of the items 3847 has purchased this season from some non-FRC suppliers.
Belts from VBeltGuys.com
We started using them in 2018 and haven't looked back. Their timing belts are cheaper than every other source we have found and they have nearly every length and width you could want. Combined with 3D printed pulleys these have made there way on to many parts of our robots over the past few seasons.
A 70 tooth, 5mm pitch, 9mm wide HTD belt is 350-5M-09. The 350 is the belt circumference which is tooth count multiplied by pitch.
Vbeltguys.com
USB Wide Angle Camera
We have been using this camera for a couple seasons as well. The wide angle lets you see a much larger portion of the field while driving.
Amazon.com - ELP 170degree Fisheye Wide Angle VGA USB Camera
Cheap PTFE Sheet
This is way cheaper than the comparable product from McMaster and from our brief testing seems as slippery on the ball as the McMaster stuff. It's possible it's not pure PTFE but it's what we are planning to use on our robot.
Amazon.com PTFE Film No Adhesive, Pure White 16 x 60 inch
PLA Pro Filament
We have been using this filament extensively this season. It has all of the benefits of PLA, fast print speeds, stiffness, and inexpensive but it's far less brittle than normal PLA and stronger. There are still times for even stronger and tougher filaments but for general printing this is our new default material.
January 26, 20202020 Day 23: Intakes and Drive Trains
Falcon Pinions
We ran into our first issue with the Falcon 500s are second batch of pinions were a tight fit on the falcon shafts which is a known issue and is discussed in that thread. We used a wire wheel brush similar to ones in this kit. It took some of the nice black finish off the front of the falcon with it but it worked to take the shaft OD down enough to get a nice slip fit for pinions. We noticed that most of the pinions prefer to go on to the shafts a certain side first. When slipped on to the shaft the other direction they seem to stop sooner but when you turn them around they slip all the way down after the wire wheel.
Protobot Progress
Our protobot intake, indexer, and drive train are coming along.
Small incremental improvement are on the way, which is why we are doing it on a full prototype robot. So we can drive it and make changes for the comp robot to handle the balls better.
Spectrum
January 27, 20202020 Day 24: CAD Update & Vision Update
CAD Updated
The STEP file on GrabCAD has been updated for this week. You can download it here - https://grabcad.com/library/spectrum-3847-2020-ultraviolet-frc-robot-1
Vision Progress
We have made a lot of progress using opensight to be able to track balls and track the rectangle on the loading bay. We are planning to use a limelight for aiming our robot and to have two additional cameras for driver viewing and tracking of balls and the loading bay.
Ball tracking is using a color filter and then selecting only circles.
The rectangle tracking is just normal shape tracking on the retro-reflective tape.
Spectrum
January 28, 20202020 Day 25: Design Review #4
January 29, 20202020 Day 26: Intake progress and motor allocations
Intake Progress
Progress on the Protobot intake and funnel have come to their 2nd iteration.
This version fixes some geometry issues with the first and removes the belt path from the center of the funnel.
Motor Allocations
We added our motor allocations to our copy of the Spectrum Design Sheet (Designsheet.spectrum3847.org)
Video
Video
Intake
Our newest intake prototype is meeting all our expectations for an intake. The balls are rapidly moved up into our robot and our new indexer should be able to sort out the 3 wide balls pretty easily in the unlikely case we are intake 3 balls all sitting next to each other.Video
Indexer
The indexer prototype based on FRC#6135 is working flawlessly.
Video of it working without intake
Video
More Pictures and Video of all the systems are available in our photo gallery.
Video of it working without intake
Video
More Pictures and Video of all the systems are available in our photo gallery.
Spectrum Dead Axle Rollers
The roller setup we have been using in our prototypes are based on a system we developed for our 2019 Cargo intake. We plan to use it again for our Power Cell intake.
The system has 6 parts
Their todo list is pretty long
- 7/8" Aluminum Tubing
- 1.125" ID x 1.25" OD Polycarbonate Tubing
- McMaster Tube Connecting Nuts for 7/8" Tube
- 7/8" ID x 1.125" OD Needle Bearings
- 7/8" Push on Retaining Rings
- 3D printed Clamp-On Pulleys
- The 7/8" tube has the tube connecting nuts (star nuts) pressed into the ends of the length you need to span and is bolted into place on the ends acting as a standoff between two plates.
- The needle bearings go in the ends of the polycarbonate tube after you cut it to length.
- The push on retaining rings hold the tube and needle bearings in place.
- The 3D printed pulley clamps over the polycarbonate tube so it can be driven by a belt.
- Any rubber tube of your choice can be applied to the outside of the polycarbonate tube to provide grip on the game pieces.
Spectrum
January 18, 2020
2020 Day 14: Controls and Everybot
Controls Update
Our controls Subteam has been working on several projects already this year.Their todo list is pretty long
- Path Following using BobTrajectory and HelixFollower
- PID tuning using the WPILib 2020 implementation
- Cameras
- Limelight target tracking
- Other software target and object tracking
- Driver camera streaming
- Control Panel Color Sensing and automation
- Ball indexing
- Scouting and Data Visualization
- Automated Subsystem Testing (based on 254 sample code)
- Improving Camera Stream Viewing
Over the past few days we have been testing OpenSight and learning to implement a simple power cell tracker.
Everybot Project
Several of our newer team members are working on building a version of the Everybot The Everybot is the model for teams with limited resources to design an effective robot. Every year there are teams that follow the Everybot documentation that have very successful seasons. Spectrum is building an Everybot so we can have a robot to practice with and we will also release any updates that we make to our version.
The kit drive base construction got under way this week.
Spectrum
January 19, 2020
2020 Day 15: Some progress
Shooter Hood
Tomorrow we will be testing some new shooter hood additions. We have yoga mat foam and PTFE sheet mounted to the hood.
Belt Tower Testing
We built a belt tower testing rig out of prototype so we can see how the balls react to each other and try to learn to prevent jamming mechanically in addition to control solutions that will come later.
Controls
Opensight was setup today to stream two driver cameras to the driver station and was using less than 3Mbps to do so. The controls team also looked into some edge detection as well.
Spectrum
We did more shooter testing today. We made several changes all at once we normally try not to do but circumstances were somewhat beyond our control. The modified VEX traction tire we had been shooting with had a failure and one of the tires broke apart. We won't be using that wheel anymore for our development of competition. It's possible it was just our implementation but we will be going with a solid wheel from here on out. We moved to 2x 6x1.5" colsons wheels we had from our 2015 drive train.
January 20, 2020
2020 Day 16: Drive Gearboxes and Shooter Testing
Shooter Testing
We did more shooter testing today. We made several changes all at once we normally try not to do but circumstances were somewhat beyond our control. The modified VEX traction tire we had been shooting with had a failure and one of the tires broke apart. We won't be using that wheel anymore for our development of competition. It's possible it was just our implementation but we will be going with a solid wheel from here on out. We moved to 2x 6x1.5" colsons wheels we had from our 2015 drive train.
We also changed the gearing to move the NEOs to 1:1.5 with a 36 tooth pulley on the NEO output and a 24t on the shooter wheel. We did some tests with the accelerator wheel on it's own NEO and then moved to a setup that had the 4" accelerator wheel ganged together with the colson shooter wheels 1:1 and only shot using 2 NEOs. The smaller diameter means that the 4" wheel will have a reduced surface speed.
We also tested our shooter with a new backing of yoga mat foam and Teflon sheet. This backing still couldn't let us nicely shoot ball #14 (a ball that has previously been sliced open multiple times in a belt prototype). Once the balls have enough cuts, rips, tares, and holes to vent at a similar rate to a new ball they become very hard to shoot.
Here is one of our tests. The one ball that lands short is the ball that has multiple cuts through the skin. It compresses far easier than the other balls and the yoga foam doesn't seem to help.
After we adjusted the angle we were able to start hitting the 3 point inner goal from approximately the initiation line.
Drive Gearbox
The test fit of our drive gearboxes was done today. The competition versions will be 1/4" Aluminum plate but we can make sure everything working out of delrin or polycarbonate on our laser cutter. We are using a gearbox design inspired from this thread by Evan Morrison. Our implementation isn't direct drive so we can simplify some things as we don't need as much reduction. The 32:12 chain reduction to the wheels will get us a large part of each gears overall reduction. The spacers are 7/8" round tube with 3D printed inserts.
Block Robot Update
More of the design is starting to take shape.
Everybot Documentation is out
The awesome people behind Everybot have released this year's build guide and a brand new website. If your team is struggling to figure out what to build, building a robot based on the Everybot is a great idea. This robot will be effective in the 2020 FRC game for a large number of teams, definitely think about if your team should be one of them, it's a really good idea. Maybe you have another idea for a ball mechanism but just want to use their climbing mechanism, that works too. No matter what reading through their documentation will make you better at building robots and give you new ideas.
Spectrum
January 20, 20202020 Day 17: Public CAD Release
CAD Updates
Today we finally reached a point with multiple systems to create our top level Solidworks assembly and add in the subsystems.
There are still a few subsystems to add but we are now working with most of the subsystems in one place with them mated in space. None of the subsystems are complete but each of the sub-teams is working on getting closer to real models for every part.
Public STEP File
We have published a STEP file of our current progress on GrabCAD. Remember that none of this robot is actually built and much of it is still in development so we don't recommend anyone using this design directly but we happily encourage teams to take inspiration from our progress and make versions of your own based on our CAD.
STEP File Download
We plan to upload a new STEP about once a week through out the rest of the season. If you haven't seen it updated in a while feel free to message us and we will try to get a new one made when we can.
Spectrum
January 21, 20202020 Day 18: Design Review #3
Design Review #3
Third Tuesday of the season means it's our third design review.
Here are a few of the slides presented to the team by the subsystem leads today.
Controls Update
More work has been done of the ball tracking using OpenSight.
Spectrum
January 22, 2020FRC 2020 Youtube Channels and Vlogs
There are a large amount of teams that post vlogs and prototype videos to youtube that don’t get seen by many people unless they are looking for them.
Several members of Spectrum have collected a bunch of these channels but we’d love to have more.
Full Sheet: vlogs.spectrum3847.org Submit New Channels: https://forms.gle/VxkR9st95uvC58y16
Spectrum
January 23, 20202020 Day 20: CAD updates
Largely we have been getting more of our subsystem designs CADed.
Shooter Design
We are experimenting with adding a rear kicker wheel to the shooter setup. The idea being to have more linear acceleration into the shooter wheel and less spin. It would be powered off the front accelerator wheel using polycord in a figure 8.
We have learned to use Solidworks surfaces to allow us to CAD a curved shooter hood and then unwrap it so we can easily laser cut it from a flat piece of material.
Funnel
The Powered V funnel (based on FRC#6135’s design), is moving along. We will have custom printed pulleys on 7/8“ dead axles with 30mm wide, 5mm pitch timing belts to move the balls along. The BAG motors will be replaced by NEO550s in the real robot.
Climbing Brake
Last year we intended to use a VP ratchet slice to hold our robot after the match, but the standard ratchet slice never really worked. We ended up using a pneumatic cylinder driving into the ratchet adapter. We may be using a similar mechanism again this year.
Spectrum
January 24, 20202020 Day 21: First Sheet Metal Arrived & Everybot Tips
Sheet Metal Arrived
With stop build day no longer existing this year we decided to move to a slightly different model. In most seasons we would build our practice bot and competition bot about a week behind each other. When we would do a sheet metal order we would order enough for two+ robots. This year we are building a protobot, a competition robot, and a practice robot. The drive train sheet metal for the prototype robot arrived today. After the get the protobot working nicely and test fitted we will release the rest of the sheet order to our sponsor to build the competition and practice robots. The practice robot will be completed after the competition this season. The protobot will also be decommissioned to create the practice robot. This is to ensure that our practice and competition robots can be closer to identical.
We are also making a larger portion of our robot our of extrusion than we have done in the past few years.
Everybot Updates
Our Everybot project is moving along. We have the KOP chassis completed to the proper size and have begun cutting down some of the stock to make the Everybot.
We have found a cheaper source for the flex ratcheting wrench used on the Everybot climber. If you have a Grainger near you, you can order it and pick up in the store with no shipping charges.
https://www.grainger.com/product/WESTWARD-1-2-3LU37
We also have been using our bench shear and aviation snips to cut the tie plates into gussets instead of a band saw. We find this to be faster and easier.
Spectrum
January 25, 20202020 Day 22: Protobot Chassis & Purchases
Protobot Chassis
We found some issues with the current design that we will be fixing before we send off the comp bot and practice bot chassis.
Purchases
Here are some of the items 3847 has purchased this season from some non-FRC suppliers.
Belts from VBeltGuys.com
We started using them in 2018 and haven't looked back. Their timing belts are cheaper than every other source we have found and they have nearly every length and width you could want. Combined with 3D printed pulleys these have made there way on to many parts of our robots over the past few seasons.
A 70 tooth, 5mm pitch, 9mm wide HTD belt is 350-5M-09. The 350 is the belt circumference which is tooth count multiplied by pitch.
Vbeltguys.com
USB Wide Angle Camera
We have been using this camera for a couple seasons as well. The wide angle lets you see a much larger portion of the field while driving.
Amazon.com - ELP 170degree Fisheye Wide Angle VGA USB Camera
Cheap PTFE Sheet
This is way cheaper than the comparable product from McMaster and from our brief testing seems as slippery on the ball as the McMaster stuff. It's possible it's not pure PTFE but it's what we are planning to use on our robot.
Amazon.com PTFE Film No Adhesive, Pure White 16 x 60 inch
PLA Pro Filament
We have been using this filament extensively this season. It has all of the benefits of PLA, fast print speeds, stiffness, and inexpensive but it's far less brittle than normal PLA and stronger. There are still times for even stronger and tougher filaments but for general printing this is our new default material.
January 26, 20202020 Day 23: Intakes and Drive Trains
Falcon Pinions
We ran into our first issue with the Falcon 500s are second batch of pinions were a tight fit on the falcon shafts which is a known issue and is discussed in that thread. We used a wire wheel brush similar to ones in this kit. It took some of the nice black finish off the front of the falcon with it but it worked to take the shaft OD down enough to get a nice slip fit for pinions. We noticed that most of the pinions prefer to go on to the shafts a certain side first. When slipped on to the shaft the other direction they seem to stop sooner but when you turn them around they slip all the way down after the wire wheel.
Protobot Progress
Our protobot intake, indexer, and drive train are coming along.
Small incremental improvement are on the way, which is why we are doing it on a full prototype robot. So we can drive it and make changes for the comp robot to handle the balls better.
Spectrum
January 27, 20202020 Day 24: CAD Update & Vision Update
CAD Updated
The STEP file on GrabCAD has been updated for this week. You can download it here - https://grabcad.com/library/spectrum-3847-2020-ultraviolet-frc-robot-1
Vision Progress
We have made a lot of progress using opensight to be able to track balls and track the rectangle on the loading bay. We are planning to use a limelight for aiming our robot and to have two additional cameras for driver viewing and tracking of balls and the loading bay.
Ball tracking is using a color filter and then selecting only circles.
The rectangle tracking is just normal shape tracking on the retro-reflective tape.
Spectrum
January 28, 20202020 Day 25: Design Review #4
January 29, 20202020 Day 26: Intake progress and motor allocations
Intake Progress
Progress on the Protobot intake and funnel have come to their 2nd iteration.
This version fixes some geometry issues with the first and removes the belt path from the center of the funnel.
Motor Allocations
We added our motor allocations to our copy of the Spectrum Design Sheet (Designsheet.spectrum3847.org)
After we adjusted the angle we were able to start hitting the 3 point inner goal from approximately the initiation line.
Drive Gearbox
The test fit of our drive gearboxes was done today. The competition versions will be 1/4" Aluminum plate but we can make sure everything working out of delrin or polycarbonate on our laser cutter. We are using a gearbox design inspired from this thread by Evan Morrison. Our implementation isn't direct drive so we can simplify some things as we don't need as much reduction. The 32:12 chain reduction to the wheels will get us a large part of each gears overall reduction. The spacers are 7/8" round tube with 3D printed inserts.Block Robot Update
More of the design is starting to take shape.
Everybot Documentation is out
The awesome people behind Everybot have released this year's build guide and a brand new website. If your team is struggling to figure out what to build, building a robot based on the Everybot is a great idea. This robot will be effective in the 2020 FRC game for a large number of teams, definitely think about if your team should be one of them, it's a really good idea. Maybe you have another idea for a ball mechanism but just want to use their climbing mechanism, that works too. No matter what reading through their documentation will make you better at building robots and give you new ideas.
There are still a few subsystems to add but we are now working with most of the subsystems in one place with them mated in space. None of the subsystems are complete but each of the sub-teams is working on getting closer to real models for every part.
Spectrum
January 20, 2020
2020 Day 17: Public CAD Release
CAD Updates
Today we finally reached a point with multiple systems to create our top level Solidworks assembly and add in the subsystems.There are still a few subsystems to add but we are now working with most of the subsystems in one place with them mated in space. None of the subsystems are complete but each of the sub-teams is working on getting closer to real models for every part.
Public STEP File
We have published a STEP file of our current progress on GrabCAD. Remember that none of this robot is actually built and much of it is still in development so we don't recommend anyone using this design directly but we happily encourage teams to take inspiration from our progress and make versions of your own based on our CAD.
STEP File Download
We plan to upload a new STEP about once a week through out the rest of the season. If you haven't seen it updated in a while feel free to message us and we will try to get a new one made when we can.
Here are a few of the slides presented to the team by the subsystem leads today.
Spectrum
We are experimenting with adding a rear kicker wheel to the shooter setup. The idea being to have more linear acceleration into the shooter wheel and less spin. It would be powered off the front accelerator wheel using polycord in a figure 8.
We have learned to use Solidworks surfaces to allow us to CAD a curved shooter hood and then unwrap it so we can easily laser cut it from a flat piece of material.
Spectrum
Spectrum
January 21, 2020
2020 Day 18: Design Review #3
Design Review #3
Third Tuesday of the season means it's our third design review.Here are a few of the slides presented to the team by the subsystem leads today.
Controls Update
More work has been done of the ball tracking using OpenSight.Spectrum
January 22, 2020
FRC 2020 Youtube Channels and Vlogs
There are a large amount of teams that post vlogs and prototype videos to youtube that don’t get seen by many people unless they are looking for them.
Several members of Spectrum have collected a bunch of these channels but we’d love to have more.
Full Sheet: vlogs.spectrum3847.org Submit New Channels: https://forms.gle/VxkR9st95uvC58y16
Spectrum
January 23, 2020
2020 Day 20: CAD updates
Largely we have been getting more of our subsystem designs CADed.
Shooter Design
We are experimenting with adding a rear kicker wheel to the shooter setup. The idea being to have more linear acceleration into the shooter wheel and less spin. It would be powered off the front accelerator wheel using polycord in a figure 8.
We have learned to use Solidworks surfaces to allow us to CAD a curved shooter hood and then unwrap it so we can easily laser cut it from a flat piece of material.
Funnel
The Powered V funnel (based on FRC#6135’s design), is moving along. We will have custom printed pulleys on 7/8“ dead axles with 30mm wide, 5mm pitch timing belts to move the balls along. The BAG motors will be replaced by NEO550s in the real robot.Climbing Brake
Last year we intended to use a VP ratchet slice to hold our robot after the match, but the standard ratchet slice never really worked. We ended up using a pneumatic cylinder driving into the ratchet adapter. We may be using a similar mechanism again this year.Spectrum
January 24, 2020
2020 Day 21: First Sheet Metal Arrived & Everybot Tips
Sheet Metal Arrived
With stop build day no longer existing this year we decided to move to a slightly different model. In most seasons we would build our practice bot and competition bot about a week behind each other. When we would do a sheet metal order we would order enough for two+ robots. This year we are building a protobot, a competition robot, and a practice robot. The drive train sheet metal for the prototype robot arrived today. After the get the protobot working nicely and test fitted we will release the rest of the sheet order to our sponsor to build the competition and practice robots. The practice robot will be completed after the competition this season. The protobot will also be decommissioned to create the practice robot. This is to ensure that our practice and competition robots can be closer to identical.
We are also making a larger portion of our robot our of extrusion than we have done in the past few years.
Everybot Updates
Our Everybot project is moving along. We have the KOP chassis completed to the proper size and have begun cutting down some of the stock to make the Everybot.
We have found a cheaper source for the flex ratcheting wrench used on the Everybot climber. If you have a Grainger near you, you can order it and pick up in the store with no shipping charges.
https://www.grainger.com/product/WESTWARD-1-2-3LU37
We also have been using our bench shear and aviation snips to cut the tie plates into gussets instead of a band saw. We find this to be faster and easier.
Spectrum
January 25, 2020
2020 Day 22: Protobot Chassis & Purchases
Protobot Chassis
We found some issues with the current design that we will be fixing before we send off the comp bot and practice bot chassis.
Belts from VBeltGuys.com
We started using them in 2018 and haven't looked back. Their timing belts are cheaper than every other source we have found and they have nearly every length and width you could want. Combined with 3D printed pulleys these have made there way on to many parts of our robots over the past few seasons.
A 70 tooth, 5mm pitch, 9mm wide HTD belt is 350-5M-09. The 350 is the belt circumference which is tooth count multiplied by pitch.
Vbeltguys.com
USB Wide Angle Camera
We have been using this camera for a couple seasons as well. The wide angle lets you see a much larger portion of the field while driving.
Amazon.com - ELP 170degree Fisheye Wide Angle VGA USB Camera
Cheap PTFE Sheet
This is way cheaper than the comparable product from McMaster and from our brief testing seems as slippery on the ball as the McMaster stuff. It's possible it's not pure PTFE but it's what we are planning to use on our robot.
Amazon.com PTFE Film No Adhesive, Pure White 16 x 60 inch
Purchases
Here are some of the items 3847 has purchased this season from some non-FRC suppliers.Belts from VBeltGuys.com
We started using them in 2018 and haven't looked back. Their timing belts are cheaper than every other source we have found and they have nearly every length and width you could want. Combined with 3D printed pulleys these have made there way on to many parts of our robots over the past few seasons.
A 70 tooth, 5mm pitch, 9mm wide HTD belt is 350-5M-09. The 350 is the belt circumference which is tooth count multiplied by pitch.
Vbeltguys.com
USB Wide Angle Camera
We have been using this camera for a couple seasons as well. The wide angle lets you see a much larger portion of the field while driving.
Amazon.com - ELP 170degree Fisheye Wide Angle VGA USB Camera
Cheap PTFE Sheet
This is way cheaper than the comparable product from McMaster and from our brief testing seems as slippery on the ball as the McMaster stuff. It's possible it's not pure PTFE but it's what we are planning to use on our robot.
Amazon.com PTFE Film No Adhesive, Pure White 16 x 60 inch
PLA Pro Filament
We have been using this filament extensively this season. It has all of the benefits of PLA, fast print speeds, stiffness, and inexpensive but it's far less brittle than normal PLA and stronger. There are still times for even stronger and tougher filaments but for general printing this is our new default material.
Small incremental improvement are on the way, which is why we are doing it on a full prototype robot. So we can drive it and make changes for the comp robot to handle the balls better.
Spectrum
January 26, 2020
2020 Day 23: Intakes and Drive Trains
Falcon Pinions
We ran into our first issue with the Falcon 500s are second batch of pinions were a tight fit on the falcon shafts which is a known issue and is discussed in that thread. We used a wire wheel brush similar to ones in this kit. It took some of the nice black finish off the front of the falcon with it but it worked to take the shaft OD down enough to get a nice slip fit for pinions. We noticed that most of the pinions prefer to go on to the shafts a certain side first. When slipped on to the shaft the other direction they seem to stop sooner but when you turn them around they slip all the way down after the wire wheel.Protobot Progress
Our protobot intake, indexer, and drive train are coming along.Small incremental improvement are on the way, which is why we are doing it on a full prototype robot. So we can drive it and make changes for the comp robot to handle the balls better.
Spectrum
January 27, 2020
2020 Day 24: CAD Update & Vision Update
CAD Updated
The STEP file on GrabCAD has been updated for this week. You can download it here - https://grabcad.com/library/spectrum-3847-2020-ultraviolet-frc-robot-1
Ball tracking is using a color filter and then selecting only circles.
Vision Progress
We have made a lot of progress using opensight to be able to track balls and track the rectangle on the loading bay. We are planning to use a limelight for aiming our robot and to have two additional cameras for driver viewing and tracking of balls and the loading bay.Ball tracking is using a color filter and then selecting only circles.
The rectangle tracking is just normal shape tracking on the retro-reflective tape.
Spectrum
This version fixes some geometry issues with the first and removes the belt path from the center of the funnel.
Spectrum
January 28, 2020
2020 Day 25: Design Review #4
January 29, 2020
2020 Day 26: Intake progress and motor allocations
Intake Progress
Progress on the Protobot intake and funnel have come to their 2nd iteration.This version fixes some geometry issues with the first and removes the belt path from the center of the funnel.
Motor Allocations
We added our motor allocations to our copy of the Spectrum Design Sheet (Designsheet.spectrum3847.org)