The Motion Analysis of Standing Up and Sitting Down Under Assistance by a Physical Therapist

This paper deals with a measuring system and the results of the analysis for the motions such as standing up and sitting down under assistance by a skilled physical therapist (PT). This measuring system is developed to evaluate the efficiency of assistance quantitatively, and is composed of the following two subsystems. One is for the position data of the each lower limbs’ joints measured by the optical camera, and the another is for the force vectors acting on the lower limbs measured by the force plates and multi axes force-moment sensor. The experiments with a sound person as a subject assisted by a skilled PT are performed. With these data, the inverse dynamics analysis is done, and the following results are obtained. The torque and power which should be generated on each lower limbs joints of the subject are reduced, when he is assisted by the PT. Especially in the hip joint, the ratio of reduction is remarkable.