Alright CD, totally hypothetically and definitely unrelated to this year’s game… what’s the secret to a linear slide that’s powered in both directions (up for lifting and down for climbing?) Some sort of rack and pinion system maybe? Pneumatics?
Chain or belt connected to the carriage, probably the most commonly used approach
Double winch (one spool pulls up, one spool pulls down, wound in opposite directions so one loosens while the other tightens)
Lead screw (limited speed though)
Lots of options.
https://www.youtube.com/watch?v=lBVcPxq1KTY
This is for an FTC scale lift, but the concepts are generally the same. Hope this helps!
Oooh, I hadn’t even thought about chain… I’ll have to look into chain lifts, right now the only way I can think of doing it is only powered one way and letting gravity do the work on the way down. Are there any good examples of this somewhere?
Man, I used to coach an FTC a few years ago and tried to build this exact lift… It went terribly, after a couple of cycles they were constantly getting slack in one direction… up would be so tight it was about to break and down would be falling off… I don’t know what I was doing wrong.
You basically just run a full loop of chain parallel to the lift, and bolt through the gaps in the links to connect to the carriage. You can drive it up and down for control in both directions.
I’ll go digging through my 2015 photos to find some more specific physical examples, this kind of structure was pretty popular then and in 2011.
EDIT: Decent shot of implementation on 148’s 2015 robot:
Vex also sells a chain attachment kit, which allows you to interface their VersaFrame system with #25 or #35 chain for exactly this use. See here.
Oooooo, that video really helps bring it together. I got it now. That’s pretty awesome.