608 Dead-Wheel Odometry Swing Arm
A spring-loaded swing arm for a passive odometry "dead wheel". It pivots on an 8 mm rod or M8 bolt and carries two stacked 608 bearings (8 x 22 x 7 mm) in a 16.5 mm hub, so your M8-bolt axle and tracking wheel stay square to the floor. Pivot to axle is 70 mm. There is a 4.5 mm hole for a spring or rubber band that keeps the wheel pressed down, and two M3 heat-set bosses 38 mm apart where you can attach your own encoder bracket. It's a cheap stand-in for commercial odometry pods on skid-steer and holonomic rovers.
robotics odometry 608-bearing dead-wheel