Research On Joystick Control And Autonomous Adsorption Of A Bipedal Wall Climbing Robot

Wall climbing robot is a kind of special robot,which can replace human beings working in dangerous or inaccessible areas,such as high altitude,radiation environment,narrow pipes and so on.Our group has developed a wall climbing robot,some control problems of which are discussed in this thesis.First of all,the mechanism of a 5-Degree-of-Freedom wall climbing robot is designed based on modularity and bionics,the robot is made up of T joint modules,I joint modules and S modules according to inchworm structure;The kinematics model is built by using D-H method,the forward displacement,inverse displacement and Jacobi matrix are deduced,the relation between the speed of swing foot in Cartesian space and the speed in joint space is analysed,and the joystick data is mapped to the speed loop of swing foot.The mapping relation is analyzed after exchanging support foot;3 typical gaits are introduced,the size of obstacle and load parameters are calculated.Secondly,the space geometric model is established to calculate the angle and distance between swing foot and wall,the necessary conditions of sealed chamber is analyzed;S module is designed according to this model using STM32 as lower computer control chip,ultrasonic sensor as distance sensor,and the RS485communication circuit,sensor signal acquisition circuit and vacuum pump,solenoid valve drive circuit are designed;Besides,lower computer is programmed to acquire the distance signal by I~2C,pressure signal by ADC,and a data reception protocol is defined between the upper and lower computer.Thirdly,the control system is built using EPOS servo controller as the CAN slave,and PC as the CAN host;A zero calibration method is designed using the Hall sensor and magnets;The control software has been developed by LabVIEW using the principles of object-oriented programming after software requirements analysis,each of the robot modules is packaged as a class to improve the scalability.Finally,the prototype experiment is carried out to verify the feasibility of joystick control,and the consuming time of adsorption may be reduced from minutes to seconds through autonomous adsorption.The prototype is 18kg,and the maximum speed is about 2m/min.