Billfred and team are likely asleep at this hour and I’m not quite asleep yet so may a I proudly present our Ri3D Robot submission for Team Cockamamie!
Ask any questions you may have about the design here and either myself, Ryan, or Billfred can answer them.
Also if you haven’t checked out the thread Ryan made about the Rev Robotics Digit Board lib he worked on for LabVIEW seen in the video you should check it out here!
Amazing!!
Wow! When I heard someone at kickoff say that a low-bar high-goal shooter is impossible, I knew someone else would do it.
Does the drivetrain get over any other defenses, or is this bot focused on the low bar to shooting path? If the drivetrain has the ability to get over other defenses, I would be interested in knowing the wheels’ size and the center wheel’s drop.
Looks like the intake is spring-loaded or something. Does that improve performance compared to a static wheel?
I can’t figure out how that catapult works; the catapult doesn’t seem to be connected to anything but its shaft. Is the potential energy stored somewhere else, then transmitted to that shaft?
Credit goes to John on this; he was adamant about the low bar.
Does the drivetrain get over any other defenses, or is this bot focused on the low bar to shooting path? If the drivetrain has the ability to get over other defenses, I would be interested in knowing the wheels’ size and the center wheel’s drop.
Can’t get over what you didn’t build. 
We built Rough Terrain because we felt that was one of the toughest ones to get over. Others were planned, but time constraints pinched us (Monday was the start of classes at USC). The wheels are 8" AndyMark pneumatic tires, and the kit frame’s drop is…1/8"? 1/4"? I don’t remember, but it’s the OEM AndyMark frame there.
Looks like the intake is spring-loaded or something. Does that improve performance compared to a static wheel?
It’s actuated by a pneumatic cylinder, though that piece of surgical tubing you see replaces that original function (pushing the ball up the ramp) for most applications. We can pull it back in for frame perimeter and to eject into the low goal. It definitely doesn’t hurt our low bar abilities to have it sitting lower than usual.
I can’t figure out how that catapult works; the catapult doesn’t seem to be connected to anything but its shaft. Is the potential energy stored somewhere else, then transmitted to that shaft?
Never underestimate the power of a CIM motor lightly geared. It’s literally one CIM, a Toughbox (maybe 12.75:1?), and the kicker you see on camera. Oh, and some pool noodle to protect everything. Drive it one way to pull it back, then swing it hard the other way to fire. I have experience with CIM-powered swinging sticks; it’s why 1618’s 2007 robot was called Uppercut. (There, it was a 5’ PVC arm and it about sent me to the canvas.) We were happy with the kick, so why mess with success?
As Billfred said we didn’t have the other defenses built yet. So we cannot claim to have gone over them, but theoretically it was made to be able to go over all of them that don’t require some active mechanisms easily. When we have the rest of the defenses built for our team we’ll shoot some additional video potentially. The frame is a modified AM14U3 I believe the drop center is 1/8".
The intake is not spring loaded. It is connected to a pneumatic cylinder that is plumbed for only lifting the intake up to center the ball in the robot, holding the ball as we drove across the field, and helping for when we would need to spit the ball out in the low goal. When the solenoid isn’t on the intake floats which allows it to move as needed to let the ball roll in and over the front geometry of the robot easily and quickly.
The catapult is that simple because mathematically speaking you don’t really need more power than what our system provided us for shooting. Since shooting from the neutral zone and secret passage is not allowed. Billfred pretty much nailed what the shooter is, and you don’t need much more than that to be successful in shooting.
Two updates from the Team Cockamamie camp:
Rock wall? Check!
Tonight, we let the Garnet Squadron kids drive it in our parking lot for some practice. After several more jumps not unlike that one (which are super fun, so I can’t blame the kids), the two sides of the drive system had noticeable camber to them. This robot was not huge on bellypan or front supports for varying reasons; the first thing we’d probably try is more fasteners on the belly pan in the front (the metal panel where the USC logo is) to tie the two sides together better. If we weren’t concerned with the low bar or if we didn’t use a kicker, we would absolutely tie the frame together in the back as well. And, of course, there’s not driving your robot like a raving lunatic.
Just things to consider if you’re giving our robot a look while you design.
…well, not sure what I expected, but that wasn’t it. Very nice way of defeating the wall.
Remember, this is only possible because we made our robot intentionally butt-heavy. Bumpers may change that, but the net CG change would probably move backwards anyway since there would be a gap in the front.
Hey, I was wondering if anyone knew what gearbox and gear ratio they have for their arm shooter?
12.75:1 on a standard Toughbox with 1 CIM motor.