Evaluation of semiautonomous navigation assistance system for power wheelchairs with blindfolded nondisabled individuals.

Some individuals with disabilities are denied powered mobility because they lack the visual, motor, and/or cognitive skills required to safely operate a power wheelchair. The Drive-Safe System (DSS) is an add-on, distributed, shared-control navigation assistance system for power wheelchairs intended to provide safe and independent mobility to such individuals. The DSS is a human-machine system in which the user is responsible for high-level control of the wheelchair, such as choosing the destination, path planning, and basic navigation actions, while the DSS overrides unsafe maneuvers through autonomous collision avoidance, wall following, and door crossing. In this project, the DSS was clinically evaluated in a controlled laboratory with blindfolded, nondisabled individuals. Further, these individuals' performance with the DSS was compared with standard cane use for navigation assistance by people with visual impairments. Results indicate that compared with a cane, the DSS significantly reduced the number of collisions. Users rated the DSS favorably even though they took longer to navigate the same obstacle course than they would have using a standard long cane. Participants experienced less physical demand, effort, and frustration when using the DSS as compared with a cane. These findings suggest that the DSS can be a viable powered mobility solution for wheelchair users with visual impairments.