Aerocraft Simulator Servo System Controlling & Parameter Tuning Techniques

Aerocraft simulator is a kind of device in hardware-in-the-loop simulation system, which can provide a highly emulational environment that can simulate the characteristics of target radiation spectra, the change of relative distance and possible interferences.This paper aims at presenting relative approaches and techniques about serial communication in servo system and PID parameter tuning of the simulator. Serial communication, which is fully developed and widely used as a communication approach, has advantages of low cost and high stability. Therefore, serial communication can be considered as a communicating method in the simulator. PID parameter tuning refers to choose the right proportional index, integral time and differential time so that the servo system could work under optimal condition. Parameter tuning is significant and crucial to controlling system. PID tuning approaches can be divided into two kinds: theoretical calculating and practical project tuning.After shortly introducing the background of hardware-in-the-loop and the simulator, type selections of the four compositions of servo system are presented in detail, which include controlling part, driving part, execution part and feedback part. Then, serial communication in servo system of simulator and PID parameter tuning are discussed. In the discussion of serial communication, the essay introduces the ASCII interface of Bakery controller that can support serial communication between Bakery controller and the motor, and the concrete procedures to implement the serial communication in VC++ environment utilizing MSComm tool. In the discussion of parameter tuning, the transfer functions of DC motor used in this project are calculated firstly. In the following, different PID parameter tuning results of simulator servo system are proposed using the classical Ziegler-Nichols Method, Cohen-Coon Algorithm and Set-Point Optimal Algorithm. These results are compared and analyzed by MATLAB. Besides, three practical project tuning approaches are introduced, including critical proportion method, cut-and-trial method and die-away curve method. CME software provides an auto-tuning function for users. The essay also includes the specific procedures to auto-tuning the parameters of simulator system by CME software. The summery of the paper and personal perspectives are given in the end.