I. Introduction
With the coming of aging societies and a shortage of people for nursing care, handicapped people, including the elderly and blind, find it increasingly necessary to be self-supporting. However, many such people suffer from injuries, poor eyesight, or a general lack of muscular strength, and need the support of other people in daily activities. In the living environment, the ability to walk is one of the most important and fundamental functions for humans, and enables them to realize high-quality lives.