Adjusting the wheelbase of a test wheelchair

The test wheelchair (TWC) is a wheelchair that enables all the necessary adjustments to be made so that the most suitable wheelchair can be ordered for a person with a disability. Loaned by a shop for a limited period, it is used to determine the characteristics of the final wheelchair to be ordered from a supplier. The aim of this project was to demonstrate the feasibility of the most complex adjustment to be made, that of the lateral wheelbase (overall width). The aim was to produce a prototype of the concept integrated into a wheelchair in the form of a 3D drawing, as well as a demonstrator of the principle. At the start of the project, the TWC was to include only lateral wheelbase adjustment, but discussions with the partners led to a change in demand and the desired settings on the TWC. The lateral wheelbase adjustment proved to be of little interest to users and was abandoned.

However, the new TWC concept had to include the possibility of adjusting seven parameters, including seat depth, front and rear seat heights, and the position of the rear wheels in relation to the backrest. In this project, we assessed the feasibility of technical solutions for these different adjustments. Some can be done with simple sliding rods, but others are interdependent and require a more complex solution. A system with two jacks was proposed as a simple, light and innovative solution. At the end of the project, we produced a 3D drawing of the TWC with all the desired adjustments, demonstrating the technical feasibility of such a chair.
The first learning from this project was the change in demand that took place during the kick-off session. Although the subject had already been the subject of a student project in 2022, and the team members had worked together to draw up the funding application, actually tackling the project generated discussions that led to the conclusion that the setting initially chosen for the TWC was not relevant.