Humanoid Robot Teleoperation with Vibrotactile Based Balancing Feedback

One of the main challenges while teleoperating a humanoid robot consists in maintaining the slave's balance while satisfying the operator's intention. The main goal of this work is to settle whether feeding back the robot's balance state to the operator by the mean of a vibrotactile belt can lead to an enhanced quality teleoperation. This study examines if an adequate cutaneous guidance can enable the operator to understand when the robot is approaching a loss-of-balance configuration, and use this information to adjust his teleoperation strategy. To achieve this objective, three different feedback patterns were compared during an initial experimental study. The evaluation focused on the subjects capacity to recognize the boundaries of a virtual workspace under each feedback mode and to adapt accordingly their teleoperated motions. The best suited feedback mode was selected and used during a second experiment which compared the performances obtained with and without tactile feedback during the teleoperation of the humanoid robot COMAN. Results clearly reveal that the cutaneous feedback of the slave's balance state leads towards an enhanced quality teleoperation combining an increased safety as well as an unrestrained use of the entire stable workspace.