Augmented wheelchair control for collision avoidance

Abstract

An electric wheelchair gives people with disabilities the ability to move independently and participate in social activities. However, the control of wheelchairs requires concentration, foresight, and spatial orientation, which often deteriorate with the progression of a disease and with age. The loss of these efficiency can be significantly compensated by the safety system. The research presented on augmentation in manual control of the wheelchair is carried out. Although most of the existing propositions focus on stopping before an obstacle, bypassing it, or automatic navigation to the indicated area, they do not resolve safe motion in tight spaces and areas with many obstacles. This article presents a new approach to collision controller for manual control. The proposed solution takes into account the situation in which the driver of the electric wheelchair uses it as a tool to move moveable objects in its surroundings. The developed and tested system provides safe and controlled contact with the obstacle. As a result, the intent to move resulting from joystick deflection causes a controlled low-speed motion of the object. This article contains descriptions of the control method and the research stand with the wheelchair, simulation results and experimental studies. The simulation model was used to analyse dynamics of the controlled object, select collision controller parameters and test controller operation. The results of wheelchair tests and simulations are similar and consistent with the assumed mode of operation, confirming correctness of the proposed control method.