Material SELECTION
Main Body, Body Seat, Back Rest, Footrest, Arm Rest, Handlebar, Actuator Case and Battery Holder
The main reason of choosing Aluminium Alloy 6061 is because the material itself is have a good strength value. The cost is of the material is also rather reasonable. The material itself has high machinability so that it can easily shape by using machining process. Making the wheelchair light is also primary objective. With the material being light, it would help so. In case of wheelchair being wet or in damp environment, the Aluminium helps to prevent corrosive.
Seat, Backrest, Armrest and Footrest (Cushion)
Even though both material has good softness, the main reason is the durability. The PVC has an excellent durability which would prevent tearing of the seat, backrest, armrest and footrest. It has a good resistance to fire and excellent resistance to water. Resistance to fire helps in case any malfunction of the battery that can cause fire. The resistance of water will help during cleaning. The PVC is also much easier to clean. Lastly, the cost is also a factor. Being it is cheaper than the other, it is a plus side to reduce cost of the wheelchair.
Seatbelt and Calfstrap
The comfortable level is quite comfortable and the material is quite breathable which would help when someone is buckle in. It can easily be clean in case if it gets dirty. It is also has a wrinkle resistance which would prevent it to be crumpled up. Cost is also a factor in it as it quite cheap.
Handlebar Grip
The grip will be the most important. Silicone has an excellent gripped. Even thou it is pretty fragile; the cost is not expensive so it easy to change or buy another one if it is damaged. It is very comfortable to grip it. Provide grip in all conditions. Therefore, even it is wet, you can still have a proper grip for it.
Tyre (Rubber)
The reason why is because it has great shock absorber. This would produce ride that are less bumpy on surface such as gravel and road. The weight of the tire would be light. This would make the wheelchair lighter. The price is rather reasonable and could help to reduce the cost of the wheelchair.
Tyre and Handrims
Making the frame into AISI Type 316 Stainless Steel is a good choice because it has good yield strength and ultimate tensile strength. The cost of material is also very reasonable. It has good machinability so it can be shape into tyre easily. It has high corrosive resistance so if it goes into water, it will not rust or damage easily.
