Research On Disturbance Rejection Control Technology For Contact-Operating Aerial Robot

Contact-Operating Aerial Robot(COAR)is a special kind of Aerial Robot which carries working equipment and interacts with working objects in the air to complete specific tasks.COAR plays an important role in more and more industries.Therefore,it is of great significance to improve the performance of its control system.In this paper,a kind of COAR,which is used to prune the tree barriers near the high-voltage power lines in the power industry,is chosen as reserch objects to study the flight control technology.The specific contents are summarized as follows:Firstly,based on Solid Works 3D drawing software,the whole structure of COAR is established.The flight principle of COAR is discussed,and two different motion states of COAR are defined.After that,the kinematics and dynamics model of COAR is built,and the model parameter uncertainty,disturbing force and moment brought by working device and model parameter change caused by contacting with trees are analyzed.It paves the foundation for the design of flight control law.Then,the controller of COAR is designed by using the sliding mode technology.Taking the finite time convergence as the starting point,the convergence and stability of terminal sliding mode and nonsingular fast terminal sliding mode are discussed.For improving the robustness of the control system,the disturbance observer is introduced to observe and compensate the lumped disturbance of the system.On this basis,the attitude and position controller of COAR is designed.Based on the analysis of the principle of the controller,the general regulation of its parameters is discussed.Then,the controller designed in this paper is implemented in Matlab/Simulink environment,and the numerical simulation experiment with compare group is designed.In order to verify the effectiveness of the designed controller,a simulation experiment is designed to simulate the process of tree barriers pruning.The experimental results show that the designed controller has good control performance and can meet the requirements of COAR for tree barriers pruning.Finally,on the basis of the previous design,the prototype of the COAR is built.The flight control law and intelligent flight logic of the COAR are realized with the help of the open source flight controller Pixhawk and STM32 embedded platform.On this basis,the program design of each function module is completed.In the end,the COAR prototype can realize the safe cutting of tree barriers with diameter less than 4.5cm,and has good flight maneuverability,which verifies the effectiveness of the design of this paper.