Adaptive Control Of Real-Time Substructure Testing

Real-time substructure testing (RSTing) is an important testing method to evaluate the performance of rate dependent structures and devices. To this end, RSTs must be performed at the correct loading rate and higher performance of hydraulic servo-actuator is demanded. Adaptive control is an approach to the control of dynamic systems with uncertain parameters. This approach may serve as a good candidate for loading control of highly nonlinear civil engineering structures. In this paper, model-reference adaptive control (MRAC) method is applied to the controller design of the hydraulic servo actuator in RST. The contents are described briefly as follows:Firstly, the design method of MRAC system is studied. An adaptive control system with an unknown mass is numerically simulated, the influence of the adaptive gain and the reference signal amplitude on control system is analyzed.Secondly, the adaptive control system for RST is designed for the case of linear physical substructures. Numerical simulations of RST with the MRAC and PID control are carried out. The results show that: the control accuracy and robustness of the MRAC are better than that of the PID control method.Thirdly, the numerical model of the servo-hydraulic system is developed for the case of nonlinear physical substructures. The satisfactory performance of the control system is show by numerical simulations.