Attitude Control And Trajectory Optimization Of Variable-pitch Quadrotor

Quadrotor,which has simple structure,good hover performance,good handling and other salient features,is currently the hot area of UAV.Unlike miniature UAVs,industrial-grade multi-rotor UAVs make extensive use of variable-pitch and variable-speed control to provide better aerodynamic efficiency and longer battery life.In this paper,aimed on the application of logistics and transport mode,variable pitch and variable speed control and track planning research are carried out.It has important practical value for applications of industrial multi-rotor UAV.First of all,50 kg variable-pitch four-rotor test prototype made by the research group is taken as the research object in this paper.The aerodynamic performance and power characteristics of the rotor were analyzed by using the combination of the blade element and the slipstream theory.Based on this,the flight dynamics model of the rotor was developed.The rotor performance is experimentally measured and compared with the calculated results,which improves the reliability of the model.Then,based on the PID control method,the attitude control and position control loop of UAV are designed.The simulation model is set up in Matlab Simulink environment,and the co-simulation between Matlab and Flightgear is realized.Finally,taking UAV logistics as an application scenario,the global path planning method is established by the ant colony algorithm to obtain the optimal distribution order.Then,the dynamic constraint condition is introduced by the differential flat theory.With minimum energy consumption and time-consuming as the goal,to screen out the actual flight program.Then the author based on the grid method to establish a local dynamic programming method,giving the UAV abilities such as real-time obstacle avoidance.