Research On Control Law Of Autopilot System Of Flight Simulator

Flight simulator plays an important role in the pilots' training. At present, flight simulators which used in all airlines of our country were imported from abroad in the proportion of 99. With the development of China's aviation industry, research and development of domestic aircraft simulator will have a positive role in development of China's aviation industry. In order to improve domestic flight simulator development and promote civil aviation,our college has done some research of simulator systems, based on 6 degree-of-freedom Stewart Platform manufactured successfully cooperated with Harbin Institute of Technology. The main content of my project is to design the autopilot system control law of simulator.As an important system to ensure automatic flight technology, autopilot system plays a very important position in the flight simulator. It affects the fidelity, flight performance of flight simulators. It is also a key index to determine the level of the aircraft simulator. The aim of this project is to design autopilot control law for large civil aircraft flight simulator. First of all, a detailed analysis was introduced about the composition and principle of autopilot. Secondly, flight simulator quality target was made according to the relevant provisions of GIB185-86 “Manned aircraft(fixed wing) flying qualities”, the nature aircraft performance of Boeing737-300 was analyzed, laying the foundation for the design of control law. The purpose of this research is to find control law suitable for large civil aircraft. Considering the special requirements of large civil aircraft, such as security, stability and comfort, the subject uses the classic control theory to design autopilot control law. The control law parameters of pitch, altitude, lateral and course model was designed with root locus method and the longitudinal and lateral control system model was established with SIMULINK. The parameters of PID controller was modified initially with the method based phase margin, then parameters were optimized with the gradient descent algorithm and SQP method embed in the optimization toolbox of SIMULINK. The optimized parameters used in the control model.Autopilot system in the horizontal and vertical channels not only meet the requirements of flight quality but also obtain a more satisfactory control effect through a lot of simulation tests.