The Separate Meter in Separate Meter Out Control System Using Dual Servo Valves Based on Indirect Adaptive Robust Dynamic Surface Control

Due to the demand for energy efficiency in electro-hydraulic systems, the separate meter in and separate meter out (SMISMO) control system attracts vast attention. In this paper, the SMISMO control system was configured with two servo valves to control the meter in and meter out separately. By designing two of the proposed indirect adaptive robust dynamic surface controllers (IARDSC) for the working-side and off-side system and setting the coupled items as estimated parameters, the SMISMO control system was decoupled into two subsystems completely. Here, indirect adaptive robust control (IARC) was employed to address the internal parameter uncertainties and external disturbances. Dynamic surface control (DSC) was utilized in the backstepping design procedure of IARC to deal with the inherent ‘explosion of terms’ problem. As thus, the proposed IARDSC could simplify the design procedure, decrease the computational cost, and achieve an improved control performance in practical use. Finally, experimental results validated the effectiveness of proposed IARDSC and showed that the proposed SMISMO control system could provide a possibility to save more energy.