Research On 3D Path Planning And Control Algorithm Of UAV

The Quadrotor has the advantages of simple mechanical design,sturdiness and durability,also has small size,low cost,and easy to carry sensors and cameras.The unique hovering ability and vertical take-off and landing characteristics of quadrotors make their use in the military and civilian neighborhoods more and more common.In the path planning process of the quadrotor,the complexity of the three-dimensional environment is higher than two-dimensional environment,and most of the current path planning algorithms are based on two-dimensional planes,so path planning will cause difficulties in the three-dimensional environment.Since the quadrotor is a highly nonlinear multivariable system with six degrees of freedom and four actuators,so quadrotor is an under-actuated nonlinear system.which caused poor stability and poor anti-interference ability in the quadrotor control system.According to the existing problems,this paper conducts the following research on the path planning and control of the quadrotor:1.This paper gives a brief description based on the uniqueness of the quadrotor structure and the basic principles that need to be followed during flight.Derive the conversion matrix on this basis,establish mathematical expressions for describing the dynamics and kinematics of the quadrotor through related theories,Make theoretical reference preparations for the construction of the next control part system.2.Improve the A* algorithm,propose a two-layer extended neighborhood search strategy,further narrow the shortest path by increasing the search direction;And improve the heuristic function based on the extended neighborhood search strategy,make the heuristic function value closer to the actual planned path distance and reduce additional expansion nodes,use the improved A* algorithm to plan the global path of the quadrotor finally.For the path generated by the A* algorithm,there is a large sudden change in heading at the turning point,and adopt the B-spline to smooth the path and obtain a smooth trajectory.3.This paper briefly describes the control principle of the control algorithm and the method of converting PID into digital PID.Subsequently,this paper builds a cascade controller with reference to the mathematical expression of the quadrotor.Due to the large fluctuation range of the attitude angle in the cascade controller,This paper proposes to add an improved fuzzy controller to attitude control.Through the analysis of the simulation results,the quadcopter can complete the trajectory tracking stably and has good anti-interference ability.4.This paper builds an algorithm for the path planning of the quadrotor on the matlab side,and build a control model to control the quadrotor on the Simulink side.This paper also build the simulation environment of a quadrotor aircraft on the V-REP side,and add the obstacles and aircraft models in the environment.Set the communication interface on the V-REP side and Matlab side and Realize the joint simulation of Matlab and V-REP.Analyze the experimental results,This paper verifies the feasibility of the path planning and trajectory tracking of the quadrotor.