Our pivot uses two pairs of Kraken X60s (4 in total), linked with a cross shaft but individually tensioned. We adapted this chain tensioner idea from 2910. The gearbox that converts to a sprocket is free to rotate around the cross shaft, but is held by the turnbuckle made from two long bolts. This architecture blends both power transmission and sprocket tensioning.
Though shown in build photos with a through-axle MAXSpline, the final pivot will have two stub axles going into the elevator.
The 2×2 crossbar in the drivetrain that frames the battery is also the attachment point for the pivot. This example of top-down design helps carry the forces of the pivot across the robot. Despite the solid mounting, the pivot can still unbolt fairly easily, should it become necessary.
The pivot serves as the mount for our radio and RSL. We expect to use our 3D printer to create better mounting options for these as we finalize the angles for our cameras.
The pivot joint does not have a natural mechanical hard stop. It uses a 1:1 absolute CANCoder, mounted off-axis as shown above. While bulky, this assembly is important to help us safely operate the robot across code restarts or power cycles.
