In my engineering class I have had several students working on a concept drivetrain that we are hoping to build before the season starts. We really like using 80/20, so that’s what we started with on the frame. We have our 3-D printed corner pieces on it along with new motor and wheel mounts. It’s a 6 CIM direct drive to one wheel and belt drive to the other 4" Vex Wheels. We have the VEX shifting gearbox in it geared for 22 FPS and 10 FPS (wanted to go slower, but they were out of stock of one of the gears we needed - but I believe they are in now, so we’ll get those in soon, swap them out and we’ll be at 18.1 and 8.4 or 6.9 if we go with the different ratio). We don’t have the pneumatic cylinders in it just yet, but will hopefully by the end of the week. Also, if you happen to have seen the 118’s drivetrain, we based it off of that concept.
If you have any suggestions or questions let us know!
Also, I tried to include this in the Extra - Discussion forum, but I wasn’t able to. I hope this is the correct location for this thread.
Could you post higher resolution picture possibly? I’d like to see what you did with the sliding wheels. From what I hear tensioning belts properly is really finicky, so if you’re just planning on pulling the wheels apart by hand until they ‘feel’ tight enough you might want to come up with a more repeatable system.
Also what are the switches with rollers attached near the center wheels used for? At least from the picture they look like switches.
Total weight with what you have in the picture?
They look like switches, but these wheels will actually actuate with pneumatic cylinders. The front will actuate together and the back will actuate together, but independent of the front. This should help with turning and maneuverability. (at least in theory, we need to test it though). (see this video for how we are hoping to make it work https://www.youtube.com/watch?v=PtRewwr59d8 )
We’ll get an updated render up also. We are new to rendering in Solidworks (making the change from Inventor) so we are a little rusty.
As far as tensioning goes we are going to use the measurements from the online calculators to drive our distances. If we have to, we can make “positive stops” between the pieces and mount to the 80/20 to set the distances.
