Kinematic Analysis of Tractor-Trailer Mobile Robot on a Sphere

In order to study the motion control problem of a Tractor-Trailer Mobile Robot (TTWMR) on a spherical container, the kinematics characteristics of the robot on the sphere were analyzed. The position and orientation of a TTWMR system are described using a generalized coordinate vector composed of six variables. Based on the holonomic and nonholonomic constraints imposed on the system, a velocity transfer matrix for adjacent robots in a wheeled multi-body robot system is proposed, and a kinematics model for the motion of a TTWMR on a sphere is established. The kinematic model is theoretically simulated using Matlab and virtually simulated using Adams for robot prototypes. By comparing the results of the theoretical simulation with the virtual simulation, the accuracy of the model is validated, providing a theoretical foundation for the control of trailer mobile robots on a sphere and practical insights for their practical application.