Our prototype drivetrain all wired up! We almost got it driving, but the cRio was out of date and not responding. Looks like we will get it working on Monday instead #excited
Any plans to put a bunch of weight on it when you drive it? It looks great, will we get to see video ?
I really enjoy the invert CIM stickers.
I’m curious to see how the hex shaft collars on the axles hold up. I’ve never seen that done on a WCD before, but it seems like a nice way to reduce machining.
Anecdote here, but we ran a virtually identical drive last year. They were okay, but we had to tighten them every few matches. We’ll probably switch to clips or bolts this year.
We are just temporarily using the collars because we haven’t had access yet to the machines in our school. We will eventually replace them though.
And yes, we will try and do a video on Monday
Looks sweet. What’s the pneumatics do for you?
I believe it’s probably for shifting, since there’s just the one tank.
Correct, all the pneumatics do is shifting.
What is the weight of it with motors and electronics and no battery?
Very cool Gear boxes! Just curious what are your gear ratios and expected fps when fully loaded with 135ish pounds?
What material did you use to mount the electronics on?
Thanks! They are from West Coast Products.
The Ratio spread currently is 2.06, with calculated FPS at 7 in low and 13.5 in high. The drivetrain is currently unloaded (50 lbs roughly,) so we can’t really tell between low and high… They are both stupidly fast. We also purchased two different gear sets, and also pinions. We can configure the drive to the following speeds: 5.5/15 7/18 5.5/18 7/20.5 5.5/11 7/13.5 (low/high)
We’ll see how many we have time to actually test.
It is a perforated polypropylene sheet. You can find them online. McMaster Carr has them in stock.
Yeah, and the programmers capped the power to 80%!
Why? You have 6 cims running at <14fps in high gear.
What kind of drive method are you using to drive it? If you are using tank drive or standard arcade drive, it would make it seem like it is really fast and hard to control. I would recommend something similar to Chezy Drive. We’ve been using Chezy Drive for the past 3 years, and it makes faster robots much easier to control, as long as you put set the gains right. 13.5 fps is fast, but not stupidly fast, which I would consider being 17+. Still anything over 10 fps is hard to control with tank.
What is Chezy drive?
Its a modified arcade drive. They use 2 separate joysticks. One to control throttle, and one to control turning. Some math actually changes the turning ratio so the robot turns in smooth arcs instead of sharp corners like standard arcade drive would. This makes full speed sweeping turns much easier, which makes the robot more controllable.
Their implementation can be found here.
That is essentially what we use but I just called it halo drive. I might just implement the “smooth arc” changes to our drive though to see what that is like.
do you have video of the drive running?
Of our prototype drive, yes. Our video guy won’t be able to render it immediately though
And just a linear drive is a bit to uncontrollable, so we are going to try to test out some different math functions for the different gears and see what handles the best.