Wheelchairs are frequently used in rehabilitation therapy for the sick and wounded. However, the traditional wheelchair widely used now has some significant drawbacks. For instance, when riding the wheelchair by themselves, the patients have to directly hold and roll the wheels, which is inconvenient and sometimes dangerous. In addition, the traditional wheelchair is usually too heavy which leads to poor portability. Moreover, the existing version of wheelchairs lacks a sense of design in its appearance.
This project plans to design an improved version of the traditional wheelchair. After trial and error, the team successfully optimized the wheelchair’s power system, wheels and chair-frame. Meanwhile, the wheelchair’s appearance is fully considered to ensure the sense of design.
(1) Design a foldable wheelchair frame which could save at least 50% of the space when folded.
(2) Design an innovative operation way and corresponding braking system which would add to the convenience of using the wheelchair.
(3) Cut down the weight and improve the appearance of the product.
(4) Contruct the 3D modelling and demonstration animations using SolidWorks software.
(5) Give a reasonable cost estimation for prototyping and mass production
l Wheelchair frame design:
A foldable wheelchair frame was designed. The engineering drawings and 3D modelling of the basic parts were completed. Demonstration animation which proved the implementability of the folding function was made. The result shows that folded chair frame can help save about 70% of the space.
l Operation method design:
An initiative ratchet wrench operation system was designed. The engineering drawings and 3D modelling of the basic parts were completed. Meanwhile, the corresponding braking system is designed. The result shows that the new operation method can eliminate the inconvenience of riding a traditional wheelchair, and the braking system ensures the safety when driving.
l Weight and appearance optimization:
Materials of the basic parts were selected to minimize the weight. Some of the bars and rods were also hollowed out for the lighted-weighted concern. The total mass of the wheelchair is 20kg and the appearance is satisfying.
l Cost estimation:
A list of the basic parts of the product was made and 3 different processing factories were consulted for their quotations. Calculating using the average of the three quotations, the final cost estimation for a single prototype is ¥2212. As for mass production, the cost could be cut down to ¥750.