Hybrid position-position and position-speed command strategy for the bilateral teleoperation of a mobile robot

In this paper a control method for the bilateral teleoperation of a mobile robot was proposed, which is combining position-position and position-speed command strategies. We consider bilateral teleoperation of a wheeled mobile robot. Our main objective is to combine position-speed command strategy, which is usual for mobile robot control, with position-position command strategy. Generally teleoperation scheme has two control modes, which are position-speed mode and position-position mode. In position-speed mode, a master haptic manipulator´s position defines the linear velocity and heading angle of the mobile robot. In position-position mode, the position of the robot is controlled based on the position of the master device. In this paper we propose a strategy to adapt a reasonable control mode automatically. Sonar sensors were used to detect obstacle range information, which is the source of force feedback to human operator. Developed scheme was tested with numerical simulations and experiments. The different types of navigation tasks were evaluated. Productivity, accuracy and usability of hybrid control strategy are analyzed. Flexible and intuitive control was achieved.