Measurement of the standing-up motion from a chair using a luminous marker system

In the field of rehabilitation, a reflective marker is commonly used to measure the physical movement of a subject, while it allows the motion measurement only from the direction in light. A new method was proposed for measuring the physical movement by using a luminous marker that emits infrared rays. This method enables one to simultaneously measure the movement from all directions due to the hemispheroidal radiation of infrared rays, which leads to the three-dimensional measurement of physical movements. A prototype system was developed, and the three-dimensional movement and physical parameters for the standing-up motion from a chair were demonstrated.