A Model-Free Cross-Coupled Control for Position Synchronization of Multi-Axis Motions

A model-free cross-coupled controller is proposed for position synchronization of multi-axis motions. The position synchronization error of each axis is defined as the differential position error of the adjacent axes in both directions, which is then coupled with the position error to form the coupled position error. A PD-type synchronization controller has been proven to guarantee asymptotic convergence to zero of both position and synchronization errors in a set-point position control. A trajectory tracking controller is further developed. The cross-coupling effect to the system stability has been investigated. The proposed method is easy to implement in practice since it is model-free and the control gains are not time-varying. Experiments are performed to verify effectiveness of the proposed approach.