The belt units of an omnidirectional treadmill need to be connected for a continuous rotational transmission with variating axes angle. Torus gearing is not appropriate due to kinematic reasons, therefore a crown gearing with cone-shaped teeth is proposed. Parameter analysis on a virtual kinematics model show that depending on the cone angle, overlaps occur at different axis angles. Consequently, the shape of the teeth is modified with tip and foot relief and optimized so that no overlapping of the teeth occurs while a large path of contact is provided.
