A Four-rotor Unmanned Helicopter Flight Controller Design

Quardrotor is a simple, unique way of flying VTOL UAV. It has broad applications in many areas. According to one kind of quardrotor, this paper concentrates on its special characteristics, mainly researched the problems on mathematical modeling, liner and nonlinear controller and flight controlling laws which are verified by simulation tests.First of all, the dynamics and kinematics equations of the prototype quadrotor are established by mathematical modeling. And the system equations are transformed to affine nonlinear form.Secondly, the increment function of small signal perturbation is derived which is regarded as the control object. On the base of work principle and linear model, Attitude controller and position controller are designed using the classical method of PID. The method and application of the controller are proposed by simulation tests. Then the feedback linearization system with the PID control is presented. The feasibility of control method is verified by the digital simulation.Then, because of the dynamic characteristics, linear controllers may have drift error. In order to efficiently, precise control, I present a controller with sliding mode based on backstepping design. Simulations show that the proposed controller is validity.Finally, by considering the basis of the actual situation, the system must be adaptive after adding disturbances to the system. And simulation show that the designed controller can achieve fixed hovering and trajectory tracking, can anti-interference that shows the system robust. And then the QPSO is used to optimize multi-objective analysis of the adjustable parameters on the system.