Flight Control System, Sensor Data Fusion Technology Research

In order to enhance stabilization, improve flight quality and maneuverability of the UAV, three methods for gaining two important feedback signals—angle-of-attack and sideslip angle that are needed in UAV control and stability augmentation system are studied in this dissertation. They are nonlinear observer, geometry relation, and multisensor data fusion estimation. Major research is listed as follows:1. The UAV's nonlinear model is built. Several mathematic models of simulation modules of UAV and the flight control laws are given.2. UAV state parameters are estimated by nonlinear observer, and the principle of this method is analyzed. Gain matrix of observer is optimized using NCD Blockset of Simulink. Nonlinear observer is designed offline and the real-time estimation of UAV state parameters is verified by the simulation using Matlab/Simulink.3. UAV state parameters are estimated using the method of geometry relation. Principle of INS/GPS system is introduced firstly, then principle of applying INS/GPS system to geometry relation to estimate UAV state parameters is studied, finally simulation results verify the real-time estimation of UAV state parameters.4. The method of utilizing multisensor data fusion to estimate UAV state parameters is proposed. Principle and method of data fusion are introduced firstly, then principle of utilizing the method of multisensor data fusion to estimate angle-of-attack and sideslip angle is studied, and verified by simulation finally. The simulation results indicate that three methods all can obtain requiredprecision. The methods of geometry relation and multisensor data fusion can both directly be applied to estimate real-time angle-of-attack and sideslip angle of UAV. The method of utilizing multisensor data fusion to estimate UAV state parameters proposed in this dissertation is innovative in certain extent, and this method enables the existing sensors to function effectively and avoid developing complicated sensors with high precision. So this method takes on the better value of project application.