Impact of lead-lag contributions of subject on adaptability of the GENTLE/A system : An exploratory study

The idea of using robots to assist a therapist with a rehabilitation exercise has led to the development of several rehabilitation robotic devices. The scope of robotic devices in rehabilitation is rapidly advancing based on the developments in robotics, haptic interfaces and virtual reality. GENTLE/S was a rehabilitation system that utilized haptic and virtual reality technologies to deliver challenging and meaningful therapies to upper limb impaired stroke subjects. The current research is working towards designing the GENTLE/A system with a better adaptive human-robot interface. This paper presents the results from an exploratory study conducted with twenty healthy subjects. The aim of the study was to identify the contribution by subject/robot during different human-robot interaction modes. Our results show that it is possible to identify the leading or lagging role of a subject during a human-robot interaction session where a reference trajectory is used to drive the arm along a path. The final goal is to use these observations to probe various ways in which the adaptability of the GENTLE/A system can be improved as a therapeutic device and an assessment tool.