Blog 1 Capstone - Team 10

Blog 1

 Over 3 million Americans use an Electric Wheelchair and among them, a popular wheelchair is the Action Trackchair. This special wheelchair is designed for users to be able to move around in all types of terrains.  This allows the user to traverse rugged terrain easily, providing mobility and access to areas that would otherwise be challenging to navigate on a more conventional wheelchair.

                      Figure 1: Action Trackchair ST (Front)

        

                                                        Figure 2: Action Trackchair ST (Back)


Among the users of this wheelchair is one of our Team Member’s brother. He along with so many others have been able to experience nature and visit state parks because of this wheelchair. However, there is a common flaw across the models of Action Trackchairs; the motors are not waterproof. According to Action Track chairs, it is recommended to not drive through water 8-10 inches deep and to not use the chair in heavy rain. This limits the track chair to traversing shallow bodies of water and would be a safety hazard if the motor stops working due to sudden heavy rain when the user is out in the wilderness. A waterproof motor would allow these wheelchair users to go out in the rain, go into shallow water, and fully experience nature. Waterproof motors are available in the market but there are none that are designed to work on the track chair without designing a new motor assembly.

Our solution to this problem is to design an enclosure that seals the motor while providing adequate cooling to the motor. The wheelchair is otherwise waterproofed, so our main focus is on the motor. The motor is mounted directly under the seat so there is little headroom above the motor. However, there is ample room to the bottom and sides of the motor to allow the footprint of the motor to be expanded.

                                                     Figure 3: The 2 motors that drive the wheelchair

The main challenge will be providing cooling to a sealed motor since sealing a motor would trap the heat inside the enclosure. The material of the casing must be able to conduct heat effectively so we are planning to use a metal for it. Our solution also requires some type of cooling device that would work in the air or underwater to cool the metal casing.


                                                          Figure 4: Proposed Casing around Motor


The motor is shown in purple. Picture for illustrative purposes only, dimensions and enclosure design are not accurate or finalized.

For the next couple of weeks, Team 10 plans on researching more about the wheelchair motors such as how much heat it produces and the Action Track wheelchair itself so we can include relevant information in our Proposal to Dr. Chen. We are also looking into different methods of cooling that will work in air and underwater to get a better understanding of what our proposed solution will look like.

 


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