ZouKeepers CAD Release and Final Notes

For those of you who have asked, here is the STEP file of our robot.

Some important notes about our CAD model:

  1. This was done in a very short time period, so there are definitely mistakes in the model.
  2. This is not a complete CAD model. Meaning some things were left out and inferred during fabrication (like the blocks for the motors/gearboxes or bearings).
  3. Some things were changed between the CAD and fabrication. This includes things like lowering the hooks on the arms by an inch, altering the location of the rollers on the elevator, using proper #35 chain sprockets instead of the #25 sprockets in the model, switching our 6" wheels to 4" wheels, changing the shape of our hooks to be stronger and to be able to detach easily.
  4. Our chassis is 4" over frame perimeter. It was designed and built prior to kick-off, so dimension rules were unknown.

If you have any questions on the CAD model or how we actually fabricated certain elements, please feel free to reach out to me.

Final Notes:

  • While our climber appears to be a very viable design, careful attention must be paid to chain stretching, axle twist, and gearbox mounting. For the chain, finding prestretched chain or tensioners could be a solution. Axle twist issues on our arm (causing an uneven rotation when climbing) could be solved by driving the axle on both ends with two separate motors. The issue of our gearbox threads ripping out may be solved by making use of the mounting holes on both sides simultaneously to split the load. This in addition to driving with two separate motors/gearboxes should cut the load on them down to 1/4 of what it is as we had it.
  • Make sure you take into account your center of gravity (CoG). You should attempt to get the CoG as close to the elevator/climber as possible to reduce swinging and the amount of torque you need to climb.
  • The elevator roller design was inspired by vex’s linear motion kit (check out the drawing file in the link). If you can custom make brackets, you can potentially make a slimmer design.
  • We didn’t spend much time prototyping an intake, but from what we did do, it’s clear that recovering balls after they start bouncing will be a big issue. Having a way to trap the ball from overhead would likely be beneficial.

I hope our videos or this CAD release will help some of you all out there. Please feel free to reach out with any questions about our design.

10 Likes

As a classroom teacher, wanted to say thanks for your ri3d sharing, it inspired some great engineering discussions.

2 Likes

Thanks for posting the videos and information. Our teams current climbing design is definitely inspired by your work. Team 5550 thanks you.

1 Like

Thank you for the file, we were just recently looking at your video :black_heart: very helpful for our brainstorming

1 Like

Would it be possible to get a parts list for this build?

Unfortunately, we do not have a BOM for this year’s build. However, if there is something specific you are looking for, I can help you source it or provide more detail

Would it be possible to get the gear ration on the WCP SS - West Coast Drive Version

I don’t remember off the top of my head. We built our chassis before kick-off and we just picked a middle tier ratio. I recommend using the JVN calculator. It has all the basic vex drivetrain gearboxes to help determine your ideal ratio for your needs.