Hello! The team that I am on is looking to build a swerve drive module in the off season as a proof of concept/learning experience. I have noticed a part that would be very helpful to us that I have seen in some photos online, but I can not find it anywhere. I have (crudely) circled in the attached photo.
Any help identifying/locating the part would be very much appreciated and would greatly help our off-season build.
Edit: To Clarify, we don’t need the exact part (though it would be nice), but the name of this type of part and where to get it would be great as well.
That is a swerve module sold by 221 robotic systems. I’m not sure if they will sell that specific part independently. But I would recommend getting in touch with them. Their very helpful people.
I’d probably best describe the part as a swerve module rotation bearing block. The creators of the system probably have their own, different name. This type of part is extremely specific to FRC, and I doubt that you’ll be able to find ones outside of FRC suppliers like AndyMark and 221 Robotics Systems.
Generally, the CD community is a lot more helpful if we know your goal. Is this to build a swerve drive in the offseason?
EDIT: Apparently I can’t read, yes, they are building a swerve drive.
If we can not find a specific part like this, anything else that will allow us to attach the wheel module to the frame while allowing the gear for rotation being attached (obviously) would be just as helpful
Edit: clarification
So I was able to design a swerve drive module like above, where one gear is attatched to the shaft, which will power the wheel. The other gear would be attatched to the frame of the module, allowing for rotation. The tricky part was attatching the whole module to the frame without messing up the rotational gear
You might want to start looking at CADs of swerves. 973 ran a mechanically solid swerve and posted their CAD. Basically you want a large ball bearing for radial loads, a thrust bearing, and some kind of gear/pulley/sprocket for rotation
According to the product page on 221 systems, they are using an oilite bronze bushing. Although a specific McMaster-Carr part number was not listed, something that fits the dimensions of your designs can surely be found on McMaster-Carr. I wish you the best of luck in your swerve project. Don’t be afraid to post here for more help if you need it, and be sure to post the final results to show what you’ve done at the end of the offseason! My team isn’t quite ready for swerve at the moment, and I always get a little bit jealous watching non-tank drive robots glide around the field effortlessly, although our WCD wasn’t too shabby this year.
Those are what some folks would call a lazy susan. I’ve also seen them called turntables. In essence, it’s a very large-diameter ball bearing. Similar to what you circled earlier, only much flatter.
What is the larger “Case” or shaft around the smaller shaft that powers the wheel?
Most folks would call that a sleeve, and it’s a second shaft that rotates the wheel.
BTW, there are more types of swerve modules than coaxial, if you wanted to try to locate some pictures. 3928 did some last year where the motor was inside the wheel; I think 16 has done some where the motor is in the module.
As others have said, those are lazy susans. I would be hesitant to use them in a swerve drive. If you put any significant side load on them (Which can happen very easily on the field), I’ve seen the bottom and top halves of them pull apart and warp, which ruins them very quickly.
After doing some research and designing, we probably will not use lazy susans for the reason you said. We do however have a possible solution for the piece pictured above.
Although it will definitely not be as eloquent as Neutrio’s swerve drive.
