FRC 1466 - Webb Robotics - 2022 Build Thread

[Jen_Lawrie]

Thanks for visiting the 2022 Webb Robotics #openalliance build thread! We’ve learned from #openalliance teams in past years, and are enthusiastic about contributing. We are team 1466 from the Webb School of Knoxville in Knoxville, TN. Webb is a PreK-12 independent day school. We’re the oldest active team in East TN. There’s a relatively large density of teams in east TN, and solid local collaboration & cooperation network.

About our team

We’ve got ~35 students and ~5 mentors. We struggle at times to have enough mentors to work effectively, but we have a mentor group with many years of FRC experience. We also have 2 FLL teams and 1 FTC team working with us in a large, shared build space at our school.

Our team has only 5 students who’ve participated at an FRC in-person regional. We’re fortunate to have a decent number of team members with FLL and FTC event experience. We attempted all of the 2021 challenges, and the team stayed engaged in FRC even after 2 seasons without in-person events.

Since 2015, we consistently registered for 2 regionals and usually play some on Saturday afternoon. We moved from a build-season-only program to one that operates outside of the competition aspect, too. We lobbied for and helped design a new robotics workspace which opened Fall 2020 in the center of our school campus.

Pre Season

Our team meets year-round (that’s FLL, FTC, and FRC together) with seasonal variation in which team members attend when. We moved back to in-person meetings summer 2020. We’ve held team workshops on power tool use/safety, participated in CAD-a-thons, ran CAD lessons using Onshape, STEM summer camp projects, and participated in the National Advocacy Conference.

We’re a mid-level resource team. Recent additions to our workshop are a Glowforge Pro laser cutter, a Nomad desktop CNC, and a small Grizzly metal lathe. Our most-utilized power tools in our lab are the drill press and bandsaw. We are hoping the laser cutter helps us with rapid prototyping early in the build season, which we practiced by helping our FTC and FLL teams with build projects.

Season Planning and Goals

Team leadership spans 10th-12th grade. We have 2 team captains and subteam leaders in electronics, design, code, media, and strategy. They’ll be sharing the responsibilities of posting regular updates here. The leadership team identified a few overarching goals for the competition season:

• Better communication within and between subteams
• Visible schedule and task planning in the lab
• Basic robot CAD by end of week 2 (drivetrain week 1)
• Reliable autonomous routines (to be defined after game reveal)
• All team members understand the game and strategy
• Improved (and consistent) organization of team materials and lab space
• Easily accessible and labeled robot wiring

Build Season Plan

Our team usually meets after school on Tuesdays and Fridays around 3:30-5:30pm. On Saturdays and some Sundays, we run extended build sessions. We try to limit scheduled build hours, but our workshop is generally open and supervised, so some FRC stuff happens outside of those times or via remote collaboration.

We are scheduled for regional events in Week 2 (Electric City) and Week 5 (Smoky Mountain). Our goal is to have a finished robot by early February, giving new drivers plenty of time to practice. We expect to build two robots - prototype bot and a polished bot done in time for events.

Other Places to Find Us

Youtube
Instagram
Facebook
Twitter
Website (update coming soon!)

Thanks for reading. We look forward to sharing our progress and learning from you all!

[Jen_Lawrie]

End of Week 1 Update

Just a little delayed with this post, with FLL and FTC events for our teams this weekend, but we’ll try to be a bit more consistent with updates. We spent kickoff weekend mostly working on game analysis and watching old FRC games to get a feel for match play and how robots interact with each other & game pieces.

Saturday 1/8 - we split into small working groups to read the game manual and complete a game summary google doc. Teams then discussed as a large group and compiled information. We’ve used a game rules test (thanks 1678!) to check throughout week 1 to see what details we know. Archived games match video we watched: 2012, 2016, and 2019 for cargo; 2013 and 2020 for climb.

General observations:

• There’s no story with with game (for the first time since 2015). Why are the robots launching cargo at the hub at an airport?
• Game pieces recycle onto the field, but are quite limited. At competitive levels of play, pushing your opponent’s cargo, holding opponent cargo, etc can make the difference in the final tally
• Mid-level climb should be attainable for every team with COTs solutions and Everybot-style climbs from 2020
• Teams that want to get the climb RP every match should be able to climb to more than one rung because it’ll be a tight fit during some quals
• Cargo RP seems less likely week 1 or 2, and I doubt we’ll see a quintet at our week 2 event
• No need to get fancy with the drivetrain, my kids immediately decided to run with the KOP (to my immense relief)

Sunday 1/9 - we worked on game analysis, ranking robot priorities, and started mocking up some field elements. The team decided they’d like to maximize RP at our competitions (week 2 and week 5). Consistent, fast climb to mid is a requirement. My kids want to focus on developing a climb from mid-to-high and then from mid-to-traversal. Getting scoring bonuses in auto and then banking on climbing points at the end will allow for versatility in teleop. My kids see defensive actions to bump launching robots or move opposing cargo as worth the effort.

Our robot Non-negotiables:
Solid drivetrain (going KOP w/ square or long config)
Climb to mid level every time in under 5sec
A practice bot done by week 4 so there’s plenty of drive time
Touch-it-own-it floor pickup
Score cargo in low hub from fender
Can score in auto (taxi/cargo)

Preferred features (by 1st regional):
Can move from mid rung to high rung
A 2 cargo autonomous (start in tarmac, backup to pick up 1, drive forward to score 2 from fender)
Can score on hub from any side

Stretch goal (by 2nd regional):
Can move from high rung to traversal rung
Score cargo in high hub from fender
A 2+ cargo autonomous (at least pick up a 3rd and 4th)

Not even thinking about:
Scoring cargo from any distance
Scoring cargo from any robot heading

On trying to climb
On 1/16, we finished modifying our 2020 climbing rung to contain the 3 properly spaced mid-high-traversal rungs to help with prototyping. (We’ll need more stability before we put full weight robots on this.) We looked at lots of 2013 climber architectures for inspiration on how to move through this challenge. Top priority is minimizing moving parts to manage and ensuring the motion connects climbing hooks with rungs.

Our 2013 scouting found a few different climb styles from 2013:
Interlocking rotary arms (1763, 3572, 4819, 2582)
Interlocking 4-bar lift (4819)
Interlocking extending arms (453, 4587)
Tilting elevators (4294, 811, 1619, 1986)
The windmill (2994)
Interlocking hook-spring (1165, 1168)
Sliding base elevator (340)

Prototyping climb
We’re still narrowing down what is a reasonable climb with CAD, cardboard, and PVC just to see how the moving parts interact. Single rotary arm and stationary interlocking hook was ruled out yesterday. With a front and back rotating arm on the robot, we still had difficulty mapping out a geometry to reach from rung to rung. Today, we’re working on the geometry to have one extending arm, and one rotating.

Prototyping for cargo
We’re looking to modify our 2021 Infinite Recharge intake and launch system for the 2022 cargo. So our robot will utilize a single-wheel hooded launcher + top roller intake. This week, we worked a bit with different wheel configurations for launcher and intake roller, but the information is not super consistent and we’ll do some follow up testing today. Our biggest yet-to-be-tested issue is figuring out deploying the intake and feeding cargo into a launcher. We don’t have a lot of experience on the team doing those things well.

[Jen_Lawrie]

End of Week 2 Update

Rough week in Knoxville, TN! We actually were only in the lab once since the previous update. The east Tennessee area is getting hit pretty hard by omicron at the moment and many schools - including ours - had to shut down. For my team, I’ve got as many precautions as I am allowed to implement in place, and so far we’ve stayed healthy. With covid numbers skyrocketing around us, though, we needed to hunker down for a few days from home. Our last day in-person was Tuesday 1/18. We’re back to work today (Sunday 1/23) with a healthy crew. The delay did at least give us some time to order parts and allow for some orders to arrive.

Drivetrain
Under construction and should be finished up during our 1/23 meeting. Looking at the climb geometry, we’re pretty sure we need the extra reach length afforded by going with the long KOP configuration. That gives us a little more room to work with when reaching out of the frame perimeter to go from mid rung to high. So chassis configuration is set: 26”x32” KOP running on 4” wheels. Why the 4”? Still enough clearance to go over the wire guides, and allows us to cut some weight. Less gear reduction to worry about. Slightly more telescoping reach and space in the bellypan for a climbing winch. We’re running with a 8:45:1 reduction in the Toughbox Mini gearboxes, powered by 2x Falcon 500’s. Mechanical team is looking at this game as involving mid to short length sprints, and want enough torque to fine-tune chassis placement in the hangar to line up for the climb.

In an effort to improve our overall assembly and maintenance, we’re switching over to using anderson powerpole connectors and snap connect CAN wire housings. These are amazing, and I’m not sure why we never switched over before. Institutional inertia, I guess? Electrical and mechanical team spent a meeting learning to use the connectors and prepping the control system and Falcon 500s. The team seems pretty pleased with the new system. We had several new students learn the ins and outs of wiring.

Climb
We’re a team looking to do cool things with a minimum number of moving parts. I tell my kids that some of our best years as a team were the ones where the robot was simple, practiced, easy to maintain, and reliable. My advice is not always heeded, but I put it out there! Traversing the rungs has my kids really interested. We’ve talked about reaching mid-rung every match as a non-negotiable, but how to get to high rung from there? Ideally, we want to pull this off with only 2 or 3 moving parts.

Current plan: telescoping system in middle of robot + rotary arm with pivot near top of robot to hook the next rung + controlled release of telescope system latch. We rigged up some PVC, bolts, hooks, and a chassis rail to see if this was even possible given the dimensions involved. We think we’re in the clear and the project moved over to the CAD team for further development.

On our one day in the lab this week in-person, we were able to start cutting some material to mock up this system more accurately. The rotary arm will be powered via belt drive. The hooks on the end of the rotary arm will likely be open U-shaped, but we’ll do some testing to see if it needs a bit more security on the bar.

We don’t want to have to pivot our elevator, and don’t want to have to actively rotate the pivot arm with the torque from the robot weight applied. Either of those options are great solutions for other teams, but not for us. In 2020, we built a custom telescoping climber from carbon fiber and delrin slides which were designed and manufactured in house. For this one, we’ve ordered a telescope kit from thethriftybot, but are ready to manufacture if needed.

Big remaining unknowns: the latch-unlatch hook on the telescoping arm. We’d like the telescoping arm to grab onto the mid rung from directly below, pushing up into the bar to latch. We’re looking at some climbers from Power Up (like 379’s) for inspiration, as well as bear jaw latches, and other similar hardware. And if we can get a latch to connect, how easily can we disengage the latch to rotate to the next bar? And how much will the robot swing? We’ll find out this week….

Cargo
Some testing with a plywood mockup of a hooded flywheel shooter. Good news: the cargo launches pretty well with high durometer 4” compliant wheels. We used those wheels in our 2021 robot, so I was not surprised. Right now, my kids are still spinning that wheel up with an impact driver, so it really needs to be hooked up to a motor for further development.

Other Good Stuff
Our FLL teams had fun at their event last weekend, and our FTC team finished 3rd at s scrimmage. On this coming Saturday, we host our first event in our new lab space: an FTC scrimmage. In addition to the typical build activities, we are also going to be working with our FTC team to set up pit spaces, competition field, practice field etc. for about half a dozen local teams.