Development and evaluation of a simulation system of electric-powered wheelchairs for training purposes

Abstract

For some people with severe physical disabilities, the main assistive device to improve their independence in activities of daily living and to enhance overall well-being is an electric-powered wheelchair (EPW). However, a large number of wheelchair users find nearly impossible to drive them with conventional EPW interfaces, so there is a necessity to offer users EPW training. In this work, the Simcadrom is introduced; which is a virtual reality simulator for EPW safe driving learning purposes, testing of driving skills and performance, and testing of input interfaces. This simulator uses a standard proportional joystick as the main input interface, and a virtual reality head-mounted display to make the experience with the system more immersive, which can also be used with an eye-tracker device as an alternative input interface and a projector to display the virtual environment (VE). A sense of presence questionnaire (IPQ), a user experience questionnaire (UEQ), and some statistical tests for performance parameters like: total elapsed time, path following error, and total number of commands were implemented to evaluate this version of the Simcadrom as a reliable simulator capable of providing a VE very similar to reality, where users can learn and improve their skills by driving a virtual EPW while training in the simulator. Afterward, a test protocol was purposed not just for comparing users’ performance and driving experience between the VE and RE, but additionally,some hypotheses were established for a deeper evaluation of the developed system. Considering the overall results, it is concluded here that the Simcadrom simulates a real EPW close enough, so it can be used for virtual training using a joystick and an HMD, or an eye tracker as an alternative interface and a projector. In general, it was well accepted by volunteers and proved to be a system that simulates, very realistically, the usability, kinematics, and dynamics of a real EPW in a VE. It was proven that people can learn and improve their EPW driving skills by doing a training session in the Simcadrom. Furthermore, the skills learned in the training session could be transferred to a real EPW.