Intelligent perception assist with optimum force vector modification for an upper-limb power-assist exoskeleton

This paper presents a method of intelligent perception assist (IPA) with optimum force vector modification for an upper-limb exoskeleton robot to assist the perception of the user to interact with environment in addition to power-assist. The exoskeleton assists not only the motion but also the perception of the user. In the case of perception assist, the exoskeleton assists user to interact with the environment by monitoring the userpsilas interaction with the environment. The exoskeleton is equipped with a sonar sensor and a stereo camera to gain information on the userpsilas interaction with the environment. When the user interacts with the environment, if the exoskeleton found any problem in the userpsilas motion, the optimum force vector modification (i.e., the modification of power-assist force vector with the optimum amount of force) is carried out by the exoskeleton to modify the userpsilas motion to solve the problem without giving any uncomfortable feeling to the user due to motion modification. IPA ensures that the userpsilas interaction with the environment can be monitored by the camera all the time by rotating the camera to track the location of the userpsilas hand. The effectiveness of the proposed concept was experimentally evaluated.