Motion control of omnidirectional mobile manipulators (Part I) - Modeling and control

Aiming at a certain kind of omnidirectional mobile manipulators,which generally consist of an omnidirectional mobile platform driven by wheels and a robot arm,an integrated kinematics model is built based on the mechanical structure and motion properties of the omnidirectional mobile manipulator.In addition,its dynamic model is deduced by Lagrangian formalism.In terms of the proposed models,two tracking controllers are designed subsequently.Stability analyses of the proposed controllers are also given. Especially in the tracking controller based on the dynamic model,the coupling torque between the mobile platform and the robot arm is analyzed quantitatively,and compensated in the tracking controller.Simulation results show the correctness of the proposed models and the effectiveness of the control approaches,and indicate that the research can be a general method for modeling and controlling a certain kind of mobile manipulators.