Research And Verification On Autonomous Planning And Control Of Quadrotor UAV With Suspended Payload

The quadrotor UAV has the advantages of simple structure,vertical take-off and landing,and strong maneuverability.The quadrotor UAVs are gradually applied to material transportation,agricultural assistance,environmental surveying,etc.The issue of the suspended load has caused concern.Due to the complex flight environment,the swing of the load,the obstruction of obstacles and various physical constraints must be considered during the flight.Using the trajectory planning to obtain an optimized trajectory can ensure that UAV reduces the swing of the load while flying smoothly.It is necessary to design a position tracking controller to ensure that the UAV stably tracks the optimized trajectory.This paper elaborates on the research and verification on autonomous planning and control of quadrotor UAVs with suspended payload.The following aspects are included:For the track planning problem of the quadrotor UAV carrying the suspended payload,this paper establishes a comprehensive model of quadrotor UAV and payload system using Lagrange equation.Based on actual flight environment,performance constraints and mission requirements,the cost function of the shortest route,avoiding obstacles and reducing the swing of the payload as performance index is designed based on predictive control and achieve quadrotor UAV spatial location planning in real time.Consider specific environmental analysis designs: Use the Cubic path in an urban environment to generate a flight path along the street;in the suburban environment,the Dubins path method is used to generate obstacle avoidance smooth paths for multiple waypoints.The effectiveness of the path planning method is verified by simulation,and the quadrotor UAV is guaranteed to reach the target point smoothly and the load swing during flight is minimal.Starting from the basic structure and principle of the quadrotor UAV,the position controller of the quadrotor UAV with payload is designed.The design adopts the hierarchical control structure of attitude inner loop and position outer loop.The dynamics model of the quadrotor UAV was established by using Newton's Euler method.After reasonable assumptions were made for linearization,use the PID control principle,the attitude controller of the angular velocity inner loop and the angle outer loop is designed.The position loop adopts a single-stage PID design.After analyzing the UAV model,the output of the position loop is transformed into the desired input of the attitude loop.The UAV and controller models were built by Matlab/Simulink.The stability and tracking performance of the position controller were verified by simulation results.Finally joint simulation is carried out and the effectiveness of the controller and path planning is verified.In order to verify the application of trajectory planning and position tracking control in engineering,this paper completed the design and construction of the quadrotor UAV experimental platform.In terms of hardware,the design and implementation of the flight control board with STM32F407 as the main control core is realized,and the hardware part selection is completed on this basis.The program design and testing of the functional modules of the overall flight control system were carried out.Finally,the application of track planning and position control with suspended load quadrotor UAV in engineering is verified by hardware debugging and flight experiments.