Development of obstacle avoidance strategy for a shared control wheelchair

Abstract

The wheelchair’s design has changed throughout the years in order to increase performance and make it safer. However, accidents do occur frequently for wheelchair users due to falls or accidental contact with the surroundings. This highlights the need for more safety on the wheelchair to reduce accidents. This research work hence investigates utilizing sensor array technology to improve current wheelchair driving safety. Ultrasonic sensors are employed together with an obstacle avoidance feature to aid wheelchair users in navigating their surroundings easily. Firstly, the choice of different types of sensors is discussed and considered. Secondly, different obstacle avoidance algorithm is explored. A new obstacle avoidance strategy inspired by previous obstacle avoidance algorithm such as the artificial potential field and vector field histogram is then derived. Meanwhile, certain existing wheelchair designs have been analysed. Next, the design process, setup of the wheelchair and the various experiments are discussed in detail too. Finally, the effectiveness of both the sensor placement and obstacle avoidance strategy is then evaluated in different situations by testing the wheelchair in corridors and an obstacle route.