Stand Assist WheelchairBy Bajaj, Shoib; Nandipati, Chaitanya; Roberts, Stephanie; Weil, Samantha; Rice, David A.; NSF 2008 Engineering Senior Design Projects to Aid Persons With Disabilities, pages 174-175
Publication Date: 2011
Description of a modified wheelchair that allows the user to work in a standing position. Designed by engineering students at Tulane University for a client who is paralyzed from the waist down, the Stand Assist Wheelchair uses nitrogen gas struts to actuate a hinged chair frame such that the footrest, seat, and seat back align in the standing configuration. The client is able to use his body weight and upper body strength to compress the gas struts and return the chair to the wheelchair configuration, thus eliminating the need for an outside active power source. The seat, back, and leg supports of the chair were replaced with three main plywood sections that are hinged together and bolted onto a standard wheelchair frame. Throughout the sitting and standing movement, the seat back and leg support maintain a vertical position by following a four bar linkage mechanism to which the sections are attached. To operate the chair, the client removes the armrest and transfers from his wheelchair using one hand. His other hand is used to push on the armrest and relieve some of his weight on the seat. As the load on the seat lessens, the nitrogen gas spring struts underneath the seat extend and the chair moves to a standing position. To return to the seated position, the client reaches back and pulls up on the armrest. The additional force on the struts causes them to compress. In addition to a knee abduction and restraint system, the client is secured by three safety straps. Total project cost was 520 dollars.
Published by: Creative Learning Press, Inc. (Website:http://www.creativelearningpress.com)
Link to text: http://nsf-pad.bme.uconn.edu/2008/Chapter%209,%20Tulane%20University.pdf