Improving wheelchair-driving using a sensor system to control wheelchair-veer and variable-switches as an alternative to digital-switches or joysticks

Structured Abstract Page Purpose Powered-wheelchair transducers and systems are presented that provided more control, reduced veer on slopes, and improved energy conservation, while reducing effort. They are especially significant for people with movement disorders who lack sufficient hand-grasp and release ability or sufficient targeting skill to use joysticks. Design/methodologies/approach Laboratory test rigs were created to test the proportional switches and to teach potential users. Then a rolling road was created and trials were conducted with the road and real situations. Caster angle measurement was selected to provide feedback to minimize drift away from a chosen course and an electronic solution was created to match driver control to caster steering position. A case study is described as an example. Findings Results and advantages are presented from changing from using a set of digital-switches on a wheelchair to a set of new variable-switches and then adding a sensor system to prevent veer on slopes. The systems have been tested for more than 18 months and shown to assist powered-wheelchair users with poor targeting skills. Research limitations The research used typical wheelchairs with caster wheels but systems could easily be used on other wheelchairs. Practical implication Simple input-devices are presented that isolate gross motor function and are tolerant to involuntary movements (proportional-switches). A sensor system is presented that assists users in steering across sloping or uneven ground. Originality/Value The proportional-switches and sensors were shown to reduce veer and to provide more control over turn and forward speed and turn radius while reducing frustration and improving energy conservation. The simple and affordable systems could be created and attached to many standard powered-wheelchairs in many organisations.. The powered-wheelchair users became more independent when using the new systems. 1. INTRODUCTION This paper presents simple systems to enable people to begin using powered-wheelchairs and to become more independent. Advantages are presented of changing from using a set of digital-switches on a powered-wheelchair to a set of new variable-switches. The work is then extended by adding a sensor system to prevent wheelchairs from veering off course on slopes. These improvements are especially significant for people with movement disorders who lack sufficient hand-grasp and hand-release ability or sufficient targeting skill to use joysticks. Instead, simple variable input-devices are presented that isolated gross motor function and that was tolerant to involuntary movements. Interacting with the variable controls was a success for several students but problems with the common caster-wheel configuration …