That looks like one HAL of a good robot. I like the x-drive and how all your base is SO close to the ground. I didn’t see the skyrise aligner that well in the reveal, would you mind giving a more detailed look at it, I’ve had a few variations of one on the ‘drawing board’ for a bit.
The claw interests me too, it seems that one piston and some sort of linkage (maybe string) could have done the job as well as the two pistons on that claw. The lift could be made more stable to reduce the wobble you showed off.
But overall HAL 9000 is a great robot, thank you for sharing your progress with the rest of the community!
Robot looks good. You may be able to get 12 points on the autonomous if you lean the pre-load against the robot and bump it on to the base. That would give you time to put two or more skyrise sections in. Just a though. You all should be very competitive.
We posted a little “joke” video a little while ago that shows an autonomous program we thought was pretty funny; that video has a fairly good view of our aligner: https://www.youtube.com/watch?v=bOhBkaLLAxA
It’s the little thing that looks like an X at the back of the robot (back meaning where the claw is, our driver had trouble with that too haha)
You can also see it in 1080p in the reveal video during the 8 point autonomous, there’s a pretty good view of it working.
Two pistons gives us more grip to the skyrise and ensures we never have to grab it more than once (unfortunately it wasn’t until our third tournament that we realized the zip ties holding the mesh in place were contacting the skyrise instead of the mesh itself, so that reduced the friction by a TON ). Also, each use of the claw (intake and outtake) only used 4 psi, and the aligner used about 10, so we had a ton of air to waste
Yeah, it wasn’t that significant of an issue. At first, we used PID to control it, but then we added 2 motors and made a few other modifications, and rather than tune it again we decided to focus on autonomous. We basically resorted to counting rubber bands to control the tilt for the most part. Marty also used a partner joystick with single-side lift control to help our driver out.
We were considering that, but the problem we came up with was a lack of accuracy in scoring the skyrise. We actually made the skyrise aligner mostly for autonomous, because there were those miniscule variations in the drive that prevented us from scoring the skyrise. However, with a cube already on the base, the aligner is not useful anymore, so we didn’t really have a choice
The skyrise aligner was a one stage scissor that moved on two linear slides. The whole mechanism fit under the robot inbetween the base and the floor. One piston was mounted to the connecting joint of the scissor linkage and controlled the retraction and deployment of the aligner. One actuation took about 6 psi because we wanted it to be able to align properly and be strong enough to stop the robot. Unfortunately we’ve already taken it apart and I don’t have any good pictures of it. I’ve attached a screen cap that gives a good look at the aligner; you can see the scissor and the attachment point for the piston. If you have any more questions, I’d be happy to answer them.
I found a nice (good view but bad quality) screenshot of the aligner
This is before we actually built the aligner and is just a crude prototype, but it gets the general idea pretty well: the scissor is the aligner, the rail is where it’s attached and slides along, the screwdriver is where the piston is attached, and the other end of the piston attaches to the joint of the aligner.
All you have to do is search for “5/32” OD Polyurethane Tubing" and a lot of results come up. Its a lot cheaper and you can buy much longer lengths and in different colors.
It’s legal if its the same in all ways except color and length (Vex only sells 5 ft lengths).
I know its legal if the color is different, however I seem to remember a Q&A about the length of the tubing. If memory serves, Karthik said because VEX only sells 5 foot chunks, then 5 feet is the longest piece you can use on a robot. (Presumably you could purchase a huge roll of it and cut it into 5 foot lengths though)