Trajectory planning of omnidirectional mobile robots with active casters: Multi-motor coordination and singularity avoidance

This paper presents a trajectory planning approach for omnidirectional mobile robots with active casters, wherein multi-motor motion coordination and singularity avoidance constraints are successfully guaranteed. These constraints, together with the velocity, acceleration, and jerk constraints, are elegantly formulated and then incorporated into an optimal control framework, which can be numerically solved by various approaches such as the direct shooting method, pseudospectral methods, and so on. An example is given by using the directing shooting method. Extensive simulation results on our developed mobile platform "NK-Omni" are provided to demonstrate the effectiveness of the proposed method.