Here is the link to all of the CAD models and renders:
https://grabcad.com/library/frc-team...swerve-drive-1
This is the swerve drive model that I created for my FRC team for future use hopefully. This is our first time working on swerve drive, but our programmers have experience with mecanum.
The model consists of 2 key components; the swerve drive pods and the dual speed gearboxes. The dual speed gearboxes are a bit on the experimental side as they do not use the traditional dog gear to shift. They instead rotate gears to mesh and unmesh on the fly. The gear ratios are 5.33 in high gear and 10.88 in low gear. Two gearboxes are put together to achieve shifting with a cylinder between them. This allows for half the needed cylinders while still having each wheel independently driven. A SRX Mag Encoder is attached to the output shaft. The output shaft then drives the swerve pod via chain and sprocket.
The swerve drive pods use a coaxial drive, with the drive power running inside the pivot shaft. The pivot shaft is a hub that clamps on a 1" x 2" rectangular tubing with thrust bearings to lower the friction. The pivot motor is attached to the 1" x 2" tubing and drives the hub with gears. The drive shaft comes to a bevel gear to rotate the power transmission by 90 degrees. The wheel is driven with a chain and sprocket, allowing for a simple change in gear ratio if needed. An electronics assembly has been added, but is still a work in progress.
Specs:
5.33 high gear and 10.88 low gear ratios
4" High traction wheels
48ish pounds as measured in Inventor (still working on accurate weight calculations)
Using the JVN Motor Calculator, I have 14.13 ft/s in high gear and 6.92 ft/s in low gear
Is there anything missing in my model? Any points of failure? Any suggestions on gear ratios or speeds? Any improvements that you can think of?
Thanks for all the feedback!
-Reed Nowling, GalacTech Robotics Engineering Design Team Leader