Dynamics Analysis Of Multiple Flexible Wheeled Suspension Mobile Manipulator

In petrochemical enterprises, it is needed to use robots to inspect storage tanks andpipelines of dangerous goods at a high speed. Combined with special working requirementsof the inspection manipulator, used accurate positioning of the end-effector for the purpose,the wheel suspension mobile manipulator has been the research object. The manipulatorelastic deformation and wheeled mobile carrier flexibility damping have been syntheticallyconsidered. Its dynamic characteristics have been studied deeply. Its dynamic model hasbeen established and the numerical simulation has been done. All above have made thefoundation for subsequent controlling strategy. Innovative work of this paper is as follows:1. Used accurate positioning of the end-effector for the purpose, based on theconstraint equations of the wheel suspension mobile manipulator system and thegeneralized coordinates separation method, the independent coordinate variables and theassociated coordinate variables of the wheel suspension mobile manipulator have beenextracted and the relationship of them have been set up.2. Based on the Euler-Bernoulli beam element theory, the Reyliegh-Rize method, thefinite element method and the Newton-Euler equation, considerd the elastic variables ofeach flexible manipulator component, the independent coordinate variables of the rigidmovement of the system, the input torque, suspension parameters, and such as road surface,the driving force models of the wheel suspension mobile carrier which contain the elasticvariables of each flexible manipulator components have been proposed and established.3. Based on the Euler-Bernoulli beam element theory and the Reyliegh-Rize method,the elastic deformations of the links of the manipulator have been described. Consideringthe elastic deformations of the manipulator, the linear elastic-damping suspension of themobile carrier, the uneven ground and amass quality of motors, the dynamic models of themultiple flexible wheeld suspension mobile manipulator have been proposed andestablished. A precise description of the physical model has been realized.4. To test different effects on the end-effector position with different dynamic models,the analysis used the numerical simulation method. The simulation result shows that it isthe necessary condition to improve the end-effector positional accuracy to consider theelastic deformations, and the dynamic coupling between the elastic deformation of thecomponents of the manipulator and the rigid motion of the whole of wheeled mobilemanipulator is the main factor that causes the high frequency vibration of the rigid motionvariables, which affects the positioning accuracy of the end-effector.