Our V3 Coaxial Swerve Drive builds upon our previous version, solving many issues we discovered. This pod uses 2 aluminum plates for it's main structure and an additional 3d printed plate to mount the servo. We designed this to have interchangeable gear ratios (600-830 RPM). By changing the pinion gear on the motor and changing the mounting of the custom waterjet cut intermediary gear, we can achieve speeds from 6-9 ft/s. The V3 utilizes the is Axon Mini MK2 for faster pod rotation, crucial for the maneuverability needed in smaller swerve drives. The wheel is the same 3d printed TPU tread design, but is now wider and crowned for rotation efficiency and more grip.
What we learned:

• DFM (milling and lead time)

• Don't use stainless steel for gears (galling)

• Be prepared for manufacturing hiccups along the way

• CAD version control

You can view the CAD here.

We don't talk of V1. Our V2 coaxial swerve drive was the only of its kind in Massachusetts for the 2024-2025 season. A swerve drivetrain consists of at least 2 independently swiveling powered wheels that when combined, can move in any direction (omnidirectional). It features many custom parts 3D printed out of a nylon carbon fiber material, laser cut plates, and most importantly, 3D printed wheel tread. The tread was designed to be printed out of TPU, with tiny spikes modeling the style of FRC treads.

What we learned:

• Don't cantilever shafts!

• Concentricity is important, especially on pulleys

• Herringbone gears must be aligned perfectly for efficiency

• Design to print without supports—unless printing TPU spikes because those can be printed as overhangs

• Make tapped holes on plates when possible

• More teams should adopt Swerve!

"What speed did you aim for your swerve last year cause that was hella fast — Student from FTC #14846 Wilmington Wired Wildcats

You can view the CAD here.

Into the Deep was another pick and place game that required a lot of vertical and horizontal extension. We decided to have both extension directions in one package. This removed the need for complex rigging and geometry for transfers, and cuts costs compared to prebuilt slides. We came up with a telescoping tube design, inspired by NUTRONs' 2023 FRC world finalist robot. Our solution is a 3 stage cascading system of square aluminum tubing that pivots around a coaxial shaft, shared with the pulleys driving the spool. That way, motors can be mounted in the middle of the robot, lowering its center of mass. The 3D printed blocks holding the bearings for each stage had to be printed over and over to adjust for perfect tolerances between the bearings and the tube itself.

What we learned:

• How to string a cascading lift! (Crucial for FTC)

• String tensioning/preventing string from hopping off the bearing

• Tolerancing and patience

• How to use sheet metal fabrication services like Fabworks

• Plate pocketing

• Efficient knee mill workflow

You can view the CAD here.