Study On The Dynamics Analysis And Navigation Control Of Tracked Wall-Climbing Robot

The wall-climbing robot(WCR)is an automatic mechanical device that can move on the vertical or inclined wall and perform tasks.The main feature of the wall-climbing robot is to realize movement and operation while ensuring reliable adsorption.Wall-climbing robot can complete dangerous tasks such as monitoring,inspection,maintenance,and engineering construction,therefore,they are wildly used in many high-altitude extreme operation fields such as construction,transportation,petrochemical,nuclear power plants,fire protection,and shipbuilding industry.Started in the 90s,researchers and engineers have developed a variety of wall-climbing robots suitable for different application fields.Among them,the tracked wall-climbing robot adopting the negative pressure adsorption method has the advantages of wide application range,good motion performance and strong carrying capacity,which has great potential for application development.In this paper,supported by the National Natural Science Foundation of China"Electromechanical coupling dynamics and adaptive control of multi-crawler travelling gears"(No.51775225),the dynamic performance and the navigation control technology of tracked wall-climbing robot are studied to meet the needs of economic and social development.The dynamic model of tracked wall-climbing robot is established,and the influence of the safe working condition and design parameters on the movement performance of the robot is analyzed.The author proposed an optimization design method of the impeller of the adsorption device and an adaptive negative pressure trajectory tracking control system for the wall-climbing robot.In addition,the trajectory tracking control experiment is carried out based on UWB/INS integrated navigation technology.Firstly,the development history and research status of wall-climbing robots at home and abroad are reviewed,and the current problems and challenges are put forward.According to the structural characteristics and movement characteristics of the wall-climbing robot,the transient steering dynamic equation,containing information about the driving motor,adsorption device,crawler device and wall,is established.In order to verify the accuracy of the dynamics model,an experimental platform is designed and manufactured for the wall-climbing robot.The accuracy of the model has been verified by comparing the simulation results with the experimental results.Based on the verified dynamics model,the effects of the safe adsorption conditions under static and dynamic conditions and the design parameters on the wall movement performance are analyzed respectively.In order to improve the adsorbability of the robot and meet the task requirements of adaptive negative pressure control during wall movement,the optimization design method of the impeller of the adsorption device is proposed.In the proposed method,computational fluid dynamics(CFD)simulation is adopted to obtain the fluid flow characteristic inside the negative pressure generating device at the working condition,and the Kriging model of the impeller parameters and the negative pressure performance is established.And then,the optimal design parameters are obtained by using genetic algorithm(GA).The trajectory tracking controller with adaptive negative pressure is designed for the wall-climbing robot.It is proposed to adjust the negative pressure of the adsorption device in real time according to the pose of the robot,so that the robot can track the reference trajectory under safe adsorption condition and low energy consumption state.The actual position,velocity,posture,negative pressure and reference trajectory of the robot are input to the controller,and the sprocket velocity and the speed of the fan motor are output to control the robot to move along the reference trajectory adaptively.According to the deviation between the actual position,speed,posture of the robot and the reference trajectory,the control variable of the movement mechanism is calculated by using the fuzzy calculated torque method.In order to verify the effectiveness of the proposed trajectory tracking controller,the simulation analysis is carried out under the straight reference trajectory and the circular reference trajectory respectively.The simulation results show that the trajectory tracking controller with self-adaptation negative pressure can adjust the negative pressure in real time according to the pose of the robot,and track the reference trajectory quickly,stably and accurately.The experiment platform for the trajectory tracking control of wall-climbing robot is designed based on UWB/INS integrated navigation.The tracking effects of the typical linear trajectory and circular trajectory are respectively analyzed.The results show that designed wall-climbing robot navigation control system can realize the trajectory tracking motion of the wall-climbing robot,and has high control accuracy.In summary,the dynamic model of wall-climbing robot is established,and the trajectory tracking control method is proposed for wall-climbing robot.Meanwhile,the accuracy of the dynamics model and the effectiveness of the control method are proved by experiment.This study provides a reference for the design and control of negative pressure adsorption tracked wall-climbing robot.