A stand alone wearable power assisting suit has been developed, which gives nurses the extra muscle they need to lift their patients and avoid back injuries. In order to put a stand alone power assist suit to practical use, sensing system and the mechanism have been improved. To stabilize the muscle hardness sensing system more, the sensor of the all-in-one design that built the sensor into meshed belt was developed and the sensing characteristic of the muscle sensor were improved. The improvement in the mechanism was advanced so that a movable range of the suit was expanded and the content of the work wearing the suit was expanded. The output torques of the actuators increased by increasing the number of the cuffs inserted into the actuators. According to the equations derived from static body mechanics using the joint angles, the necessary joints torques for maintaining a position were calculated by an embedded microcomputer and the necessary joint torques were combined with the output signals of the muscle sensors to make control signals. An exoskeleton for measurement having the same frame and potentiometers as the power assisting suit was developed. The muscle forces were measured by applying the exoskeleton to the human body and it was proved that the each unit of the suit transmitted assisting torque directly to each joint, and by wearing the suit to the body the weight could be lifted by half or less muscular power, i.e., muscular power became twice or more.
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