The NavChair Assistive Wheelchair Navigation System

TLDR

The obstacle avoidance routines used by the NavChair, combined with ultrasonic sensors, are adaptations of methods originally developed in mobile robotics research. The NavChair Assistive Wheelchair Navigation System is developed to reduce cognitive and physical demands of operating a power wheelchair for people with diverse impairments, and to advance smart wheelchair technology and shared‑control systems that adapt to human behavior. The NavChair builds on a commercial wheelchair by adding a DOS computer, ultrasonic sensors, and an interface module, and operates in three modes—general obstacle avoidance, door passage, and automatic wall following. Performance testing of the three operating modes demonstrates their functionality.

Abstract

The NavChair Assistive Wheelchair Navigation System [19] is being developed to reduce the cognitive and physical requirements of operating a power wheelchair for people with wide ranging impairments that limit their access to powered mobility. The NavChair is based on a commercial wheelchair system with the addition of a DOS-based computer system, ultrasonic sensors, and an interface module interposed between the joystick and power module of the wheelchair. The obstacle avoidance routines used by the NavChair in conjunction with the ultrasonic sensors are modifications of methods originally used in mobile robotics research. The NavChair currently employs three operating modes: general obstacle avoidance, door passage, and automatic wall following. Results from performance testing of these three operating modes demonstrate their functionality. In additional to advancing the technology of smart wheelchairs, the NavChair has application to the development and testing of "shared control" systems where a human and machine share control of a system and the machine can automatically adapt to human behaviors.