Development of closed-fitting-type walking assistance device for legs and evaluation of muscle activity.

A walking assistance device using a flexible shaft was developed. The combination of a flexible shaft with a worm gear was successfully adopted on this device to simplify its appearance and reduce its size. A hybrid - control system on this device controls both torque and angle at the ankle and knee joints. In this system, the torsional spring constant of the flexible shaft is taken into account by the motor in controlling the power and angle of rotation of the motor. To expand the area in which a person may use the device, it is equipped with a self-contained system powered by a Lithium-ion battery and controlled by an SH-4 microcomputer and actuators, consisting of motors and gears, all of which are carried in a small backpack. Consequently, persons using the device may walk freely in both indoor and outdoor environments.

Walking assistance apparatus using a spatial parallel link mechanism and a weight bearing lift.

A prototype for a walking assistance apparatus for the elderly or motor palsy patients was developed as a next-generation vehicle or movable neuro-rehabilitation training appliance, using a novel spatial parallel link mechanism and a bearing lift. The flat steps of the apparatus move in parallel with the ground; the apparatus can support entire leg alignment (including soles) and assist; walking behavior at ankle, knee and hip joints simultaneously. In order to respond the variation of equipped person's walking velocity, the length of stride and walking cycle while walking with wearing the apparatus were compensated by using the relation of walking ratio. Therefore the apparatus can be controlled in response to equipped person's will. Motor palsy and muscle weakness patients can walk by themselves by using the apparatus; patients who have ambulation difficulty can use the apparatus with weight bearing lift that we developed. Using the apparatus with the weight bearing lift prevents stumbling and enables input of walking movement to the brain motor area. It is very effective for rehabilitation to use the apparatus with the weight bearing lift. This newly developed system facilitates motor palsy and muscle weakness patients in the rehabilitation program.