Identification and analysis of pneumatic polishing force control system based on least square method

In this paper, a pneumatic polishing force control system taking Siemens S7-1200 as the key control element is developed, and the closed-loop control is realized by multi-sensors feedback. Then the pneumatic system is identified and analyzed by the time domain identification method and the least square method. According to the experiment results the system model based on the least square method identification has higher accuracy than the time domain identification method. Nyquist stability criterion is used to analyze the stability of the identified model based on the least square method, which satisfies the stability criterion and can be used for system simulation analysis. It provides excellent choice to solve the complicated modeling problem of pneumatic polishing force control system.