Designing swerves seems to be a trend as of late, so I figured I would take a stab at it too! Over the past few days, I created my take on a differential swerve. I took a great deal of inspiration from Aren Hill’s (971) swerve module here.
My goal was to make the differential swerve as small & light as possible while keeping it a reasonable speed and possible to make. Each swerve module is powered by two neos, geared for a hair above 16 ft/s free speed with a 2.75in 3D printed wheel with 1” Blue Nitrile Tread. It is geared a little fast, but with the two neos I believe it’s a good balance between top speed and acceleration.
The differential has two 84T VEXpro gears, each with a 46 Tooth bevel gear milled into them. The large 46 tooth bevel gear and the custom 10 tooth bevel gear is the part of the design that would be the most complicated to craft. Instead of machining the bevel into the 84 Tooth gear, you could bolt a bevel gear on with little modification to the design.
At the center of the differential there is the fully 3D printed “Wheel Carriage”. It is held to the differential by eight (four top and four bottom) 0.5in OD bearings set in groves machined into the 84 Tooth gears of the differential. The Wheel carriage also holds the main 4in OD 3.5 in ID bearing (can be found here ).
The module is designed to be nested into a one by two drive rail (as shown in the 6th picture).
Physical specifications for each module are:
Weight: 3.84lbs (as said by Inventor)
Due to the module being nested inside the side rail, it only takes up 4.45 in each corner from the inside of the side rails (dimensions seen in first image).
This module could also use two Cims or mini-Cims. However, it would need to be modified to include an encoder for speed. Currently, the built in neo encoder would be used for speed/distance whilst an absolute encoder would be used for the angle of each wheel carriage.
All the aluminum and carbon parts could be machined on a three axis CNC mill or router, and all the 3D prints would use a MarkForged Mark Two 3D printer.
Critics and questions are, as always, more than welcome!