Research On Docking Mechanism Design And Control Of Self Weight Spherical Robot

At present,the international self reconfigurable modular robot industry is developing rapidly and has a bright future.The demand of modular robot research and development in the world is also increasing.High mobility self Reconfigurable Intelligent spherical robot can be used in the fields of extraterrestrial detection,disaster relief and national defense security to complete the tasks of anti-terrorism reconnaissance,data acquisition,cooperative stacking obstacle crossing and cooperative external operation.It has the advantages of variable configuration,cooperative movement and cooperative operation,so it has important application prospects.Docking mechanism is the key module of self reconfigurable modular spherical robot,and its performance plays a decisive role in fast and effective docking and reconfiguration transformation of self reconfigurable modular spherical robot.In this paper,the docking mechanism of self reconfigurable modular spherical robot is studied,and the configuration design and control of the docking mechanism are mainly carried out.Firstly,the docking mechanism is designed.Secondly,the kinematics and contact mechanics of the docking process are modeled.Secondly,the docking control strategy for the self reconfigurable modular spherical robot is studied.Finally,the docking system simulation experiment platform is built for experimental verification.The specific work contents are as follows:Firstly,the design requirements and technical indicators of the docking mechanism are determined according to the application scenario.Based on this design,three docking mechanism schemes are compared,and the "cone rod" type is finally selected as the best design scheme of the docking mechanism.The four working stages of the docking mechanism are analyzed,and the working principle of the docking mechanism is clarified.The strength and stiffness of the main stressed parts of the ball head are checked,and the results are analyzed from the following aspects The maximum allowable error range of docking mechanism is analyzed from the perspective of structure,and the tolerance zone of key components is selected;the headset communication interface is used for wired communication between docking mechanisms,and Modbus communication protocol is adopted,and the frequency and speed are determined.Secondly,the kinematic models of the active docking mechanism on the self reconfigurable modular spherical robot and in the simulation experiment environment are established respectively,which lays the foundation for the follow-up simulation and experiment;the calculation model of the contact force between the ball head and the receiving cone in the docking process is established by using the L-N contact mechanics model of the virtual power principle,which lays the foundation for the follow-up research of compliant docking control Set the foundation.Thirdly,a flexible docking control method based on impedance control is adopted to reduce the contact force in the docking process.The control variable method is used to analyze the influence of the damping coefficient,stiffness coefficient and inertia coefficient in the impedance control method on the docking system,and the parameters suitable for the docking mechanism are determined.The docking function of the docking mechanism and the effectiveness of the flexible docking control method are verified by setting the selected parameters and using MATLAB and Adams to carry out the docking co simulation on the self weight spherical robot.Finally,the simulation experiment platform of self reconfigurable modular spherical robot docking mechanism is built,and the device selection and parameter setting of the experimental platform are discussed.The software control system and electrical control system of the experimental platform are designed.Through the physical experiment,the error range of the docking mechanism and the effectiveness of the compliant docking control method are determined.