Haptic interfaces for wheelchair navigation in the built environment

A number of countries have recently introduced legislation aimed at ending discrimination against disabled people; in the United Kingdom the Disability Discrimination Act (1995) provides the disabled community with new employment and access rights. The intention of the act is to help those who rely on wheelchairs for mobility and who frequently find that not all buildings provide conditions suited to easy access. Central to these new rights will be an obligation for employers and organizations to provide premises that do not disadvantage the disabled. This work reports on the development of instrumentation that allows wheelchair navigation within virtual buildings and can assist architects in identifying the needs of wheelchair users at an early design stage. Central to this project has been the need to provide a platform that can accommodate a range of wheelchair types and will map intended wheelchair motion into a virtual space. This interface must have the capacity to provide feedback to the user reflecting constraints present in the physical world, including changes in floor surface characteristics, gradients, and collisions. Integrating visual and nonvisual sensory feedback correlating to the physical effort of wheelchair propulsion has been found to augment the perception of self-motion within the virtual world and so can create an effective instrument for use in the study of wheelchair accessibility within the built environment. This project represents a collaborative effort between architects and bioengineers engaged in research related to platform design, construction, and interfacing, while testing and evaluation has been accomplished with the assistance of user groups.