The Research Of Optimal Control And Attitude Estimation On Quadrotor

Benefited from the development and application of science and technology in recentdecades, quadrotor aircraft become a high integrated control system in the composition ofseveral subsystems (navigation, communication, power and flight control, etc.) using variouskinds of micro sensors. It improves remarkably in structure, weight, manufacturing andassembling. Due to the unique flight characteristics, not only can it vertically take off and land,but it easily accomplishes tasks such as recognition, collision avoidance of obstacles. It canserve as an intelligent inspection robot to replace human in unattended industrial field, andcomplete a variety of dangerous work that workers faced in the safety test. This will promotethe intelligent level of inspection, improve the efficiency of the inspection work andmanagement and reduce labor intensity and operational costs. Quadrotor aircraft manifestsextremely high research value and application potential in the field of military and civilianareas.In this thesis, the main research work and result are summarized in following aspects:(1) Considering the project background, development history of the quadrotor aircraftwas introduced. After reviewing its research status at home and abroad, existing technicaldifficulties of the aircraft are summarized and briefly described. At last, the current existingmain research methods are set forth.(2) Starting from general structure and control principle of quadrotor aircraft prototype,we made detailed analysis of its force situation in motion. With presupposition, the quadrotoraircraft dynamics model is established ignoring secondary disturbance factors.(3) Taken elaborate analysis on the material selection, the mechanical structure quadrotoraircraft’s fuselage is determined according to the design demand. Then taking the controlrequirements and required functions into account, we design overall structure of the flightcontrol system, complete the aircraft hardware system, finally set up quadrotor aircraftcomplete machine.(4) At first pretreatment method to sensor data is expounded. Next, the principle anddiscrete recursion formula of four filters are respectively explained and deduced. Whenalgorithms are transplanted to the micro-controller, and their performance can be tested viagraphical data curve displayed on the computer, and analyzed respectively each filter’sadvantage and drawback.(5) Firstly, the variable speed integral PID control algorithm and the sliding mode control algorithm based on backstepping are respectively introduced. According to theirprinciples, the corresponding control laws are designed. In the Matlab/Simulink environmenta system model for the two kinds of controller has been set up. Through the coupled fourindependent channel control structure of aircraft system, the attitude and displacement loopsimulation perform to verify the validity of the method. In the end, designed flight controlprogram adopts the variable speed integral PID algorithm to test vehicle performance.