Hybrid Force/Position Control of Multi-Mobile Manipulators for Cooperative Operation Without Force Measurements

In this paper, considering the difficulty of the interaction between the multi-mobile manipulators and the environment, the dynamics model of the mobile manipulator is analyzed, and a hybrid force/position control method based on the prescribed performance is proposed to improve the stability of the multi-mobile manipulators in the process of cooperative object transportation. Firstly, the dynamics model of the underdriven system of the multi-mobile manipulators is established by the Newton-Euler theorem. Then, the equivalent control theory is adopted for underdriven system, and a prescribed performance control method is proposed by considering the motion interference between the mobile manipulator and the high precision control of the manipulator. At the same time, an adaptive impedance control method is used to overcome internal and external disturbance during the cooperative transport of multi-mobile manipulators. The stability of the proposed method is analyzed through the Lyapunov stability theory. Finally, the effectiveness and superiority of the proposed scheme are verified through a simulation of multi-mobile manipulators collaborative object transportation.