Design of a modular wheelchair with posture transformation capabilities from sitting to standing

A significant part of world's population is handicap, with majority suffering from lower body disabilities - the body waist down is paralysed or weak. In many of such cases, upper body of the affected person was found to be deemed fit and was able to perform all tasks, if feasible. Being able to transform posture from sitting to standing position independently, helps perform routine jobs with ease, increases employment prospects and improves blood circulation to name a few. Most of the existing wheelchair designs are expensive because of the electrical and electronics involved requiring added maintenance, or contain a variety of subsystems thus decreasing reliability. The objective is to further increase the posture transformation capabilities in terms of cost, user effort, maintenance and life. The modular wheelchair allows the user to use his/her own energy and bodyweight to shift from sitting to standing position and back, in single smooth movement with zero dependency on electrical/electronic parts. Detailed design of links, mechanisms and load calculations were performed as per standard requirements. Prototype of the proposed design was also made and successfully tested for all its design features and capabilities as per the design standards and conditions of physically challenged people.Implications for rehabilitationFive bar link mechanism helps to reduce manual effort.There is no dependency on auxiliary power source.It is a low cost rehabilitation solution with increased posture transformation capabilities.Increased body movements will help to increase self-confidence of disabled person.Easy sitting and standing capabilities will improve overall bodily functions and remove psychological barriers.