Apex Robotics is proud to publicly release our 2018 robot CAD, available on GrabCAD and natively in Onshape, and Technical Documentation. We’ve gotten a lot of questions recently from teams interested in our drivetrain CAD, so we figured we might as well clean it up and post the whole thing.
The model contains most of the details although some changes and small components that were built-to-fit or made during competitions were never added. The model also includes both sets of wheels, the original 6” pneumatic tires and the Colson+Omni configuration we used from our 2nd district event through Champs.
Use MKCAD libraries, they’re very good and super handy
Definitely do use part studios for multiple parts. It’s one of Onshape’s best features.
Don’t put the WHOLE robot in one part studio like we did. At some point during the design it will become impossible to have more than one person in the main part studio. Break it up by subsystem or something.
The interface will take some getting used if you’re coming from another CAD program, especially assembly mates with mate connectors. But once you get it you won’t want to go back.
“Replicate” is your friend for bearings, spacers, shafts, bolts, wheels, etc.
*]I’ve found that Firefox plays nicer with it than Chrome or Edge/IE.
At some point I’m going to actually get around to putting an article together with Ty Tremblay from 319 about using Onshape for FRC that will go into lots of details with tips and tricks we’ve learned.
Are those AndyMark elevator bearing plates or custom plates with a similar design? In any case, did you run into any alignment issues with the lateral bearings mounted on the bent flanges? I’m a fan of the one piece design on principal but wondered about the sheet metal tolerances.
They are the Andymark plates, arranged in a modified configuration. We didn’t have any issues with the alignment, though it’s worth noting that the lateral bearings are actually nylon rollers on a brass sleeve running directly on a #10 bolt, so it’s not a super tight tolerance assembly in that dimension.
The plates worked great. We bought a full set of spares knowing that we were running them in a slightly different configuration than designed and those are still new in the bag, we never touched them. Having used the VexPro ones before, these are definitely heavier and beefier. In this case we wanted the beef, given the amount of load being dumped into them when climbing.
I was going to ask about the single part studio if u didn’t bring it up! The way 319 structures their cad looks more promising, a single part studio per sub. Is there any trick to deal with mirrored assembles like gearboxes? or do you just have to grind out an opposite hand version?
Yeah, we’ll be picking up some of 319’s methods for the future.
Unless there’s been an update since build season that allows mirrored assemblies, you have to put it together yourself. I searched for options when we were doing the drivebase and came up with nothing. It’s definitely a highly requested feature so we will probably see something in the future.
All that being said, most subassemblies are very fast to put together in Onshape thanks to how they do mate connectors and the aforementioned replicate feature, so it’s not too much of a pain for the level of complexity we deal with in FRC.
Sub-assemblies are flexible by default in Onshape. If an assy needs to be mirrored, we typically leave the mates that would be affected out of the sub assembly and mate the parts accordingly in the assembly above.
