The 4 inch (100mm) aluminum Mecanum wheel set (2x Left, 2x Right) allows your robot to easily move forward and backward (reverse), laterally, diagonally, or spin in a circle. Each roller has a plastic sleeve bearing. Nexus part# 14162.
This set of wheelchair motors makes great heavy duty robot motors. One left motor and one right motor. They are right angle gear drives with a release and electric brakes. They are 24VDC and the operating speed is 120 RPM.