Adaptive control for a mulit-axis hydraulic test rig

Multi-axis hydraulic rigs are widely used in industrial testing applications but still represent a challenging area for control system design. This paper considers the control of a six degrees-of-freedom Multi-Axis Shaking Table driven by six hydraulic actuators. The strategy adopted employs adaptive decentralised position control, i.e. each axis has its own adaptive controller. The scheme developed is based on a cascade Minimal Control Synthesis (MCS) approach, which is a class of Model Reference Adaptive Control (MRAC). The theoretical background to the controller is presented, together with the results of an experimental study. Performance is compared with three other fixed gain control schemes. The new adaptive scheme has superior disturbance rejection and command tracking capabilities