Swerve Module Question

[adlai]

Thank you.
I assumed I would need to support the module at the bottom and the top. What I was especially curious about was where you get your delrin, how you mount it to the rest of the module and frame, and if you use small bearings or rollers around the arc to lower friction. I can see how the top bearing would work, seeing as it is a smaller radius.

Another decision i have to make is whether to have one CIM + gearing within each module or to use miter gears and transfer power through the pivot(using outside gearboxes and a sprocket.) The price and inconvenience of mounting the CIM inside the module points me in the other direction, but I was wondering whether one miter gear rotating around the other while they are spinning at high RPM causes problems. I guess now that I think about it it wouldnt really matter, you just need to make sure that your pivot is very precise so that your miter gears maintain good mesh no matter what angle the one that rotates with the module is.

[Al Skierkiewicz]

Adlai,
The delrin bearing is cut from a sheet using standard machining technique. It is a "z" shape through the cross section but with the vertical at right angles to the horizontal pieces. This allows the circular plate at the bottom of the module to hold the delrin in place once the module is mounted in the robot. I have been under the impression that bevel gears are just too lossy for this application. We have always mounted the motors inside the module. We have used drill motors, Fisher Price Motors and the small Chalupas. As I remember, the gear box uses standard gears cut from gear stock and mounted on shafts with bearings in the side plates of the module. Even with the Chalupa, the module ends up just slightly larger than the length of the motor with a gear on the shaft. The wheel is mounted almost touching the motor case and the gear box is just off to the side of the wheel. As you can imagine, using crab drive does bring the wheels closer to the center of the robot since the turning radius of the module must fit inside the outer dimension of the robot frame.