Determination of Feet Elevation for the Development of a Robotic Squat-Assist Device

Squatting is considered to be the natural, traditional and widely followed posture for defecation and hence it is a practical solution to avoid constipation. However, due to musculoskeletal issues and changes in lifestyle, it is difficult for the older population to follow squatting posture. A semi-squat posture has also been recommended by the researchers which is closer to the squatting posture. This study is aimed at determining the required feet elevation so as to achieve 30° angle between the torso & legs during semi-squat posture to facilitate smooth bowel movement. For this, two feet elevated postures, upper body up-right and upper body bending forward, have been considered. Using anthropometric data such as body height, body-segment lengths and certain assumptions, feet elevations in both the postures have been estimated using trigonometry. The feet elevations to achieve 30° angle between the torso and legs in upper body bending forward posture are smaller and hence it is considered to be an optimal posture that can be achieved by the users without much strain. The result of this analysis will facilitate in developing a squat-assist device for elderly to tackle constipation.