Constrained Outlines: A Method for Creating Access Guidelines for Individual Wheelchair Users

Abstract

A novel method of identifying solutions for wheelchair access problems is presented. This method was developed in response to difficulties in identifying manoeuvring space requirements, particularly of wheelchair users with large or nonstandard wheelchairs. A simple theoretical model of wheelchair manoeuvring is used. This model allows scaled drawings of the wheelchair outline to be constrained on an adaptation plan, in a way that provides a useful representation of the space required during individual wheelchair manoeuvres. The method can allow speedier assessments, encourages the identification of novel and individual solutions and provides a simple visual account of decision making.

Contrary to basic kinematic modelling, during tight turns, wheelchairs can slide sideways by non-negligible magnitudes: Collision risks may be increased

“…(The wheelchair rear was also raised prior to 'ii)' for 175/225 turns but this is not discriminated in the results: the motivation was that it was observed in the pilot study that if the wheelchair was initially unloaded, then as the turn progressed, fixed wheel groundcontact displaced laterally from the initial wheel-equator position (Figure 3). ) 1: number of turns for independent variables: operator, turn direction, radii (grouped by rolling combinations), total mass, 1 Non-standard loadings 40%-60% rear-front on hard floor, 2 On carpet 3 Contrived turn-set: lateral drift opposed.…”

“…One aspect of that satisfactory understanding comes from modelling the displacements wheelchairs can and cannot make when turning, that is wheelchair kinematics. Some aspects of wheelchair kinematics are fully understood and variously described [2], [3], [4], but this article will argue, one aspect potentially important to collision-free wheelchair user experience requires further engineering attention. The fully understood aspect is this basic kinematic description, conventional wheelchairs can turn with any radius of curvature.…”

Posters

“…A novel tool, constrained-outlines (Abraham and Johnson 2006), is being developed for many types of wheelchairs and wheeled disability vehicles by the application of engineering science (Abraham 2012, Abraham et al 2013. Occupational therapists can use these research based tools by following a few straightforward rules (Abraham et al, In press).…”

Abstracts

“…Occupational therapists within adaptation services have a key role enabling assisted wheelchair access. However, there is no published method of modifying architectural guidelines to account for individual physical factors (Abraham and Johnson 2006) such as occupant weight, chair size and assistant strength. This project aims to develop a transparent method of incorporating individual physical factors into the determination of the space requirements of assisted wheelchair users.…”