A tactile language for intuitive human-robot communication

This paper presents a tactile language for controlling a robot through its artificial skin. This language greatly improves the multimodal human-robot communication by adding both redundant and inherently new ways of robot control through the tactile mode. We defined an interface for arbitrary tactile sensors, implemented a symbol recognition for multi-finger contacts, and integrated that together with a freely available character recognition software into an easy-to-extend system for tactile language processing that can also incorporate and process data from non-tactile interfaces. The recognized tactile symbols allow for both a direct control of the robot´s tool center point as well as abstract commands like ldquostoprdquo or ldquograsp object x with grasp type yrdquo. In addition to this versatility, the symbols are also extremely expressive since multiple parameters like direction, distance, and speed can be decoded from a single human finger stroke. Furthermore, our efficient symbol recognition implementation achieves real-time performance while being platform-independent. We have successfully used both a multi-touch finger pad and our artificial robot skin as tactile interfaces. The evaluation of our tactile language system was done using test persons that had to learn to language symbols, perform certain missions, and finally report on their experience using the NASA Task Load Index.