Can we stop calling it “cheesecake” yet? I’ve never been one for euphemisms. I prefer to call things what they are. In this case, it should be called the collaborative effort of multiple teams to build one of the craziest contraptions I think I have ever seen in my 11 years of FRC experience. Granted, that’s a mouthful so maybe “cheesecake” is easier to say.
I’m very proud of my team. My students are amazing and our other mentors are a dream team so let me start by describing the robot that my team constructed over build season. It was an impressive feat of engineering. It had a swerve drivetrain (yeah, first time we’ve ever done that and we did it during build season). It had an onboard Nvidia Jetson board that was processing video footage in realtime using cascade classifiers to detect the recycling bins (which don’t have retroreflective tape).
Mechanically we built an arm that could extend over 7 feet and grab a recycling bin from the step. It could do it autonomously and then slam it into the ground before doing it a second time. It wasn’t fast but it was awesome. Oh, did I mention that along the way we had to redesign adapter plates to drive the arm using two AndyMark 4-Stage GEMs? We tried it with a single 5 stage but we corkscrewed a 1/2" steel shaft. We also destroyed some AndyMark raw boxes. We dealt with alignment issues and taught our students about overhung loads at not one but two regionals and even at the championship.
We also used carbon fiber tubing to reduce the weight of the arm so we could actually get a bin from the step without tipping over (at least all the way). We had originally built a claw that was made from balsa wood and carbon fiber layups that our students did in our own lab. That claw didn’t work mechanically though so we ended up having to redesign it and rebuild it for our second regional using aluminum tubing that was bent by hand because we couldn’t easily get access to a bender.
And let me tell you, that second regional was a doozy. We were a “sleeper pick” by the number one alliance. They picked us because we complemented their alliance and we helped them boost their scores high enough to come out above the others’ average. We helped them go on to win the event. We couldn’t have done it without them and they couldn’t have done it without us. We worked collaboratively.
It was an amazing robot but I’m not proud of the robot. I’m proud of what my team did to build it and make it work. This all brings me to what happened on the Curie field between my team and three of the other best teams we’ve ever had the pleasure of working with.
Much has been said about it already. Some people seem to think that 1114 or 148 pressured a poor helpless 900 and 1923 into doing whatever they said… HAH! As if. Have you even met my team? We built a 7 foot lever arm supported by two 1/2" steel shafts with 1/8" keys trying to drive a dynamic 20 pound load… we’re not just stubborn, we’re insane. No, no one pressured us into anything.
It all happened because we were hungry to win. We knew getting those cans off the step was the key to winning. Over build season we built a robot to do it after all. We built that robot for regionals and we knew it wasn’t enough for championships but we had to get there first. We knew what it would take to win. We had seen 1114 working on a really complicated mechanism in their pit and we decided maybe they were on to something. While our drive team was playing matches and keeping “Go Big” (that’s the robot’s name by the way, the practice robot is named “Go Home”) working on Friday the pit crew and scouts were hard at work trying to find out what it would take to mount those mechanisms onto our drive base.
It turned out what it would take was a new drive base. Swerve is heavy and hard to program. It’s a great drivetrain but it wasn’t needed for what we were going to do. If this was going to work, it was going to take some out of the box thinking. So we did what we do… We bought more stuff from AndyMark (thank you to all of the AM crew, you are all amazing). We bought an AM14U2 kit (KOP chassis) and a pneumatic kit. Our pit crew went about assembling a new drive base and getting a crash course in pneumatics. We left the pits on Friday night with a plan and a new drive base. The electronics from the old robot were stripped once we were done with our last match.
We left and then did what teams do in St Louis. We went to the arch and had dinner. Then we went back to the hotel. Another mentor on the team stayed a little later and got some contact info for another mentor on 1114. We had gone back to the hotel with the plan to put the KOP drive base into CAD and then stuff the electronics in. It was a miracle they all fit. Then, we found out something else from our Canadian friends. The drive base we had assembled needed to be even smaller.
So we made it smaller and stuffed the electronics in tighter. We then sent the CAD files over to 1114. Yeah, that’s right, two teams working collaboratively in CAD the night before alliance selections to build a robot from parts at the arena. It was an impressive feat. It wasn’t over though. It needed to go from CAD to robot the next day. It also wasn’t a sure thing. Someone else could have chosen us for alliance selections just to mess this plan up… if anyone even knew what we were doing.
The next morning we took the robot apart and then set to work rebuilding it all. We have a time lapse video of it coming together. Zebracorns and Simbotics mentors and students working shoulder to shoulder. Our pit became a tangled mess of components, tools, robot parts, and human beings. I’m sure it was a spectacle for all of those around us.
The integration testing was a challenge. 1114’s programmer had code written for this whacky contraption but we kept running into issues with our Talon SRXs in PWM mode. It was likely a bunch of loose cables but we solved it by just adding more of them onto the robot. We ended up with 10 of them on there instead of the 7 we had planned.
The device, dubbed “Crossbow” by 1114 was a masterpiece of engineering. It used electric solenoids as firing pins to launch harpoons sprung by surgical tubing at the recycling bins. These harpoons then retracted along with the 4 stands that were spread out from the robot. The stands came together in a tangled mess of wires, pneumatic tubing, nylon line, and aluminum. It was spectacular. And there were safety stops build into every aspect of this thing. There were pins built into it for transport, along with multiple lines in case of failure, which wasn’t likely, the lines were dynamic and designed to withstand far more force than those harpoons could ever put on them.
At this point, it was about 2:00 in the afternoon and we had missed all of the inspectors packing up on the Curie field but Ed, being the amazing LRI he is, had us covered. Did I mention that while we were doing all of this, the rest of the alliance was out winning the Curie field? We missed the handshake with the opposing alliance in the finals because we were packing up the robot and bringing it to the field inspection station.
The inspection process reminded me of inspections from when I was a student. It was a frenzy of duct tape, filing, and zip ties. The inspectors were fantastic. They were helpful, courteous, and kept a good sense of humor throughout the process. It was intense but a lot of fun. We had to trim about 6 pounds of weight from the robot. We dropped the steel weights on each of the stands and then went on to cut out some wire and surgical tubing. Did I mention the bill of materials? According to the inspector, it was one step above a napkin. I told him we were going to give it to him on a napkin but we decided typing it in Notepad was a little better. I can’t thank the inspectors enough, they were great to work with even though they didn’t cut us any slack.
Once we were through with inspection we went about practicing the setup and teardown of this contraption. It was a complicated monstrosity. Four pods plus the robot. We had it down though. It could be setup quickly and transported onto the field. If you saw us on the side of Einstein, that’s what we were doing.
Was it an elaborate ploy? A threat of mutually assured destruction in a literal arms race? Maybe. Maybe not. We were ready to deploy it and it had been tested. I don’t know if it would have worked on the field and I don’t care. The experience of working alongside 1114, 148, and 1923 to build something so insanely complicated so quickly was astonishing. We now have some incredible stories to tell and we’re going home with another banner. We were on the number three alliance in the world and for that, I’m ecstatic.
We took a robot built collaboratively over the course of a day all the way to Einstein. That’s the stuff of legends in FRC. The students and mentors of 900, 1923, 148, and 1114 aren’t going to forget this experience. We worked well together and created something amazing. We fought hard and did what we had to do to win. In the end, we didn’t make it as far as we were hoping to, but we were ready to go all the way. The hunger was there.
To our alliance partners, thank you. Everyone on 900 is awestruck by what we did together. The students and mentors of 148, 1923, and 1114 are an inspiration. It was a pleasure working with you.
I’ll leave you with something I’ve been pondering. I really want to know why it takes 3 days to build a robot. Our alliance can do it in 7 hours and we can take it to Einstein.