Dual-drive gantry stage decoupling control based on a coupling model

A Dual-Drive Moving Gantry Stage Robot can be modelled as a square MIMO system. However, it is usually considered as two independent SISO systems: classical industrial gantry control is achieved by two independent position controllers. This control structure does not take into account the mechanical coupling between the two actuators and leads to a reduction of the overall performances of the system. In this paper, a physical lumped parameters model of an industrial robot is proposed and experimentally identified. It is based on a structural, modal, and Finite Element Method analysis. Then, a physical model-based control structure is deduced. The solution is finally simulated and implemented on an experimental test bench. Results are compared to the performances of the initial industrial control and show an improvement of the overall performances.