A joystick interface for tongue operation with adjustable reaction force feedback

This paper proposes a novel tongue-operated joy- stick device for severely disabled persons. The human tongue has superior movement and tactile sensations. By providing force information during the device´s operation, user can skillfully control life supporting equipment, such as electric powered wheelchairs, robotic manipulators for meals through interaction with this equipment. Therefore, we designed a joystick mechanism that enables not only the generation of control commands for the equipment but also the adjustment of the reaction force during its operation. The adjustment of the reaction force enables the user to know if there is any interference between the equipment and the environment and to improve task performance. In our proposed mechanism, the elastic pins surround the tip of the joystick and restrict its movement by this contact. The reaction force is controlled easily by adjusting the support length of the elastic pins. This paper describes the detailed mechanism and its basic performance through several experiments.