The Study Of Small-scale Unmanned Helicopter Flight Attitude Control

In modern today, especially in the military field, small unmanned helicopter is gradually replaced by the helicopters and fixed-wing aircrafts. Because of some advantages of low cost, good motor performance, completing various combat mission and no casualties etc, it has been widely concerned.The paper studies the flight attitude control of small scale unmanned helicopter, and chooses“Raptor 50 V2”small unmanned helicopter model as the research object. The paper introduces linear motion eqution of small unmanned helicopter, and small unmanned helicopter longitudinal and lateral simplified model is sured by adopting system identification method. For the first time the PID controller based on genetic algorithm control longitudinal model, and using MATLAB simulation software to make the pitching angle step response simulation. The simulation results show that the PID controller based on the genetic algorithm not classical control PID, which performance and control effect are much better. According to the simulation results and the original reference data of small unmanned helicopter, adjusting the parameters and optimizing longitudinal model.The linear optimal control theory based on the genetic algorithm is one of the important research points we discussed.In the small unmanned helicopter longitudinal control,the control system of linear optimal control theory design based on the genetic algorithm more stable than the stability of quadratic control.The optimal control method the paper adopts after optimization,obtain the best weighted Q array and R array. When the appointed Q and R are certain,then the Riccati equation has a unique solution and only.This paper selects MC9S12XS128 microcontroller of Motorola company as the main controller, and comes true control of servo and transmission of data. In data transmission, the data is transimitted and displayed on the control system data display terminals based on the MFC write by using the wireless module and data protocol.The display based on MFC makes the system’s efficiency higher and real-time processing speed faster. In serve control section, adjusting its duty cycle can obtain the adjustment of small unmanned helicopter attitude.