Full time wheelchair users are at a height disadvantage during many function activities, such as transferring or reaching. Retrieving objects from the ground or a higher shelf while seated in the wheelchair can be both difficult and unsafe. Lateral transfers between surfaces at different heights can be difficult and unsafe. Sit-to-stand transfers are made simpler with a higher seat. This research project seeks to assist reach and transfers by designing a system to raise and lower a wheelchair seat over a 4'' range. The project included several needs assessment: 1) by conducting interviews and surveys, identify design needs from different stakeholder groups; 2) analysis of stakeholder groups' feedback and synthesis into design criteria; and 3) creation of design concepts for the adjustable height wheelchair seat; 4) evaluation of the design by setting up heuristic evaluation criteria and perform user testing; 5) design revision design based on user's performance and feedback. The design process included fabricating and testing of various concepts, validating design through user testing, and addresses technology transfer of the device.

Thesis (MScPhysio)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Aims: To assess the effect of a chair and computer screen height adjustment on the neck and upper back musculoskeletal symptoms in an office worker. Methods: An N=1 study was conducted using the ABC design. Ethics approval was obtained for the study and the participant provided informed written consent. The participant was assessed over three four week phases as she performed her habitual computer work. The outcome measures assessed during the three phases were the pain intensity and perceived sitting comfort. The three phases were named the baseline, intervention and wash-out phases. During the baseline phase, the outcome measures were obtained at the participant‟s habitual work station. The intervention phase involved a vertical adjustment of the chair and computer screen height. The wash-out phase allowed the participant to adjust the chair and computer screen height to their choice. A follow-up interview was conducted with the participant three months after completion of the study. The mean values and the ranges of the pain intensity and perceived comfort were obtained and compared. The data collected was captured on a Microsoft Excel 2010 spread sheet, where after the data was tabulated and presented graphically. Results: The mean pain intensity of the participant increased slightly during the intervention phase in comparison to the baseline phase, but remained stable during the wash-out phase. The mean perceived sitting comfort deteriorated initially during the intervention phase, but improved later during the intervention phase and showed greater improvement during the wash out phase. The perceived sitting comfort showed more improvement than the pain intensity during the washout phase. Both the pain intensity and perceived sitting comfort showed improvement at the three months follow up assessment, post completion of the study. Conclusion: The vertical height adjustment of the chair and the VDT did not improve the participant‟s pain intensity and perceived sitting comfort when compared to the participant‟s habitual workstation parameters. The findings do not favour the horizontal viewing angle. The findings of this study however support the use of „slightly below horizontal‟ viewing angle as being conducive to reduce the pain intensity and improve the sitting comfort of an office worker. / AFRIKAANSE OPSOMMING: Doelstelling: Om die effek te bepaal van die hoogte aanpassing van die stoel en rekenaarskerm op die nek en bo-rug muskuloskeletale simptome van 'n kantoorwerker. Metodes: „n N=1 studie was uitgevoer deur gebruik te maak van die ABC ontwerp. Etiese goedkeuring was verkry vir die studie en die deelnemer het ingeligte skriftelike toestemming verleen. Die deelnemer was ge-evalueer oor drie vier week-lange fases terwyl sy haar gewone rekenaarwerk verrig het. Die uitkomsmetings ge-evalueer tydens die drie fases was pyn intensiteit en waargenome sitgemak. Die drie fases was genoem die basislyn, intervensie en uitwas fases. Gedurende die basislyn fase was die uitkomsmetings by die deelnemer se gewone werkstasie ingevorder. Die intervensie fase het 'n vertikale aanpassing van die stoel en rekenaarskerm behels. Die uitwas fase het die deelnemer toegelaat om haar stoel en rekenaarskerm se hoogte aan te pas volgens haar keuse. 'n Opvolg onderhoud was gevoer met die deelnemer drie maande na die voltooiing van die studie. Die resultate was vasgelê op 'n Microsoft Excel 2010 data bladsy, waarna die data getabuleer en grafies uitgebeeld is. Resultate: Die gemiddelde pyn intensiteit van die deelnermer het effens toegeneem tydens die intervensie fase in vergelyking met die basislyn fase, maar het stabiel gebly tydens die uitwas fase. Die gemiddelde waargenome sitgemak het aanvanklik verswak tydens die intervensie fase, maar het later verbeter tydens die intervensie fase en het aangehou verbeter tydens die uitwas fase. Die waargenome sitgemak het groter verbetering getoon as die pyn intensiteit tydens die uitwas fase. Beide pyn intensiteit en waargenome sitgemak het verbetering getoon by die drie maande opvolg evaluasie, na voltooiing van die studie. Gevolgtrekking. Die vertikale hoogte aanpassing van die stoel en rekenaarskerm het nie die deelnemer se pyn intensiteit en waargenome sitgemak in vergelyking met die deelnemer se gewone werkstasie parameters verbeter nie. Hierdie bevindinge is nie ten voordeel van die horisontale kykhoek nie. Nietemin, ondersteun die bevindinge van hierdie studie die gebruik van die "effens onder die horisontale" kykhoek as bevorderend om die pyn intensiteit te verminder en die sitgemak van 'n kantoorwerker te verbeter.