Paper Title
Development of Achilles Tendon Pushing up Type Simultaneous Thigh and Calf Stretching Device for Nursing Care

In this paper, a novel mechanism achilles tendon pushing up type simultaneous thigh and calf stretching device for nursing care was proposed and evaluated. Physical therapists treat their patients to prevent a subject ankle joint’s contracture and improve their walking function. Still, sufficient rehabilitation therapy cannot be done due to the ankle joint rehabilitation demand labor-task. There has been a long demand for the self-rehabilitation system to reduce the labor task, and the rehabilitation system is operated by a physiotherapist operating the machine. The self-rehabilitation has not been realized so far. In our method, a mechanism of pushing up the foot rest under the achilles tendon to stretch thigh and calf muscles simultaneously was proposed. We developed two types of the devices using aluminum frame and linear actuator(s) as basic study. The simple one linear actuator pushing up mechanism can realize the simultaneous thigh and calf stretching, but there is unbalance problem of instability due to the Achilles tendon of both feet riding on one actuator. Next, a device that pushing up the Achilles tendon by placing only one foot on the foot rest was developed. By measuring the stiffness of the thigh and calf using muscle durometer, about 25 cm pushing up process occurs 42.4 / 21.2 = 2.0 times large stiffness values of the calf, and it means that simple Achilles tendon pushing up process generates the stretching of the thigh and calf. The proposed system could realize a stretching of thigh and calf muscles simultaneously by simple pushing up of the subject Achilles tendon using a linear actuator. And by using a ankle joint angle fixing plate, the stretching effect was increased. This mechanism maybe relief the burden on nurses / physical therapist of the heavy work of ankle joint stretching for preventing a bedridden old man