Body Scanning Scheme of Electronic Massage Chair Using a Simple Load Current

Nowadays electronic massage chairs are much more interesting in health and healing products. The relaxing effect is dependent on the proper strength for the accurate muscle position. To improve the relaxing and massaging effect, the controller has to scan and detect the human body with an effective method. The proposed body scanning scheme uses the reflected load current from the massage ball and the human back body. The y-axis motion control motor drives the massaging part from the head to the hip position. Then, the z-axis motion control motor drives the massage ball in the forward direction to scan the displacement length between the massaging part and the human backside at the fixed y-axis position. Each detected z-axis displacement data array according to the y-axis position can be used to the basement z-axis strength. Furthermore, the shoulder position can be estimated by the slope of the z-axis displacement data. From the neck to the shoulder boundary, the slope of the scanning data is suddenly changed. From the curvature of the slope, the shoulder position can be estimated by the body scanning together. In the experimental verification, the proposed body scanning scheme shows the accurate shoulder position estimation at the same time as body scanning.