DEVELOPMENT AND VALIDATION OF SIMULATORS FOR POWER WHEELCHAIR DRIVING EVALUATIONS

Of all those people with severe physical and cognitive disabilities who are rated as unsafe to drive a power wheelchair and hence denied a wheelchair, a significant number can have positive outcomes by using advanced control interfaces and by getting adequate amount of driving training. This dissertation research presents development and user evaluations with a virtual reality based wheelchair driving simulator system. Using the software systems validated in these research studies clinicians can select and customize joystick interfaces that can optimally use their client’s physical and cognitive capabilities. When people with traumatic brain injury and cerebral palsy used the isometric joystick they committed equivalent or lesser driving errors than when they used the conventional movement sensing joystick to drive a wheelchair. Potential wheelchair users can benefit from such customizable control interfaces to reliably and safely control their power wheelchairs and improve their community participation. \ud An immersive virtual reality simulator was further developed as a driving training and evaluation tool. People with various disabilities completed a clinically validated driving evaluation protocol in real and virtual environments. Their virtual driving performances in the simulator were predictive of their performances in real world. Experienced clinicians showed high inter and intra rater reliabilities in their driving evaluations. Research was also performed to understand the relative contribution of different system components of the simulator system to the overall mental and physical workload of users. This research may assist researchers in selecting simulator system components that best suit the clinical needs of potential users. Clinicians who were trained to evaluate wheelchair driving using this system and wheelchair users who used it gave a general positive feedback that that this simulator has good potential for use in clinical or community settings