Analysis of Reaction Times and Time-Delays Introduced into an Intelligent HCI for a Smart Wheelchair

Time-delays are introduced to an intelligent HCI for an intelligent wheelchair and the effects of time-delays are investigated. The ability for wheelchair users to complete tasks is considered. Two systems and two different ways for drivers to interact with their wheelchairs are considered in various situations. Wheelchair drivers were scrutinized while they completed a task with their wheelchair. Time-delay was introduced and wheelchair users undertook tests with and without sensors and a computer system connected in order to assist the driver. As the delay was extended then more failures were recorded. When the time-delay was longer or when the wheelchair was moving through more complex situations then users did better when assisted by a sensor system. The effect of introducing a delay between a joystick and a motor controller is investigated. It is suggested that in simpler situations with a shorter time-delay then little sensor assistance was required but more assistance was needed in more complicated situations or when the time-delay was longer. So it might be better to vary the sensor support provided depending on the difficulties being encountered.