Boost

What it does

Imagine pushing a 300lb individual up a hill in a wheelchair. For many caregivers, this is a frequent problem that often results in long-term injuries. Boost is a retrofittable add-on that motorizes a manual wheelchair and is controlled by the caregiver.

Your inspiration

My cousin has special needs, and his mom is deeply involved in the special needs community. When she discovered I was going to study design in school, she told me about a friend of hers whose son has Dandy-Walker Syndrome. My aunt put me in touch with her friend who explained how her son tires easily, so she regularly pushes him around in a wheelchair. This is no problem on flat ground, but they live in Colorado, so she frequently pushes her 300 lb son up steep hills. Not only is this exhausting for her, but it also leads to back and wrist pain. My research showed that this problem is shockingly common, and I want to do what I can to help.

How it works

For the user interface, there are two layers that snap to the handles. The inner layer fits snugly, the outer layer is free to slide, and there is a button in between. Pushing the wheelchair slides the outer layer to hit the button and engage the motors. When the user lets go, the motors turn off. I used a Raspberry Pi micro controller to program the system. There are four assist levels (including no assist) that provide increasing levels of motor power and can be quickly changed by pressing another button on the handle. There are three LEDs to indicate which level is active and an overall on/off switch as an added safety feature. The motors are attached to small wheels. The whole motor unit is held snugly on top of the back wheels via easy-to-install metal connectors that provide enough friction between the wheels to make the wheelchair move. Lastly, there are fenders that snap in place over the motor units to protect fingers from being pinched by the wheels.

Design process

After talking with my aunt’s friend about her unmet needs, my aunt connected me with more people in the special needs community. I spoke with caregivers, wheelchair users, therapists, and even a mobility device engineer to better understand the problem space. From here, I synthesized my findings into insights and user needs that drove my ideation. I began with the user interface portion and began brainstorming interactions. I used these ideas to make low-fi paper and popsicle stick prototypes, and I began another round of interviews. I took the findings from the interviews to refine my user needs and pick a design direction. After that, I began 3D modeling the handles, motor attachments, and fenders. I went through multiple prototypes, but the most notable was the motor attachments. Everything I 3D printed either broke or did not hold the motors steady enough for use. I eventually switched to using metal attachments and learned that sometimes you need to step back and look for new answers. I also programmed the Raspberry Pi and built the electronic system – including a step-down module and motor controller – from scratch. Then, I fit all the pieces onto the wheelchair to make a working prototype. Please see my portfolio for more details.

How it is different

I found that, while powered wheelchairs are great for independence and mobility, they are also heavy, expensive, and require a high level of fine motor skills and reaction time. Wheelchairs are not always needed for people with cognitive disabilities, so caregivers will usually opt for the portability of a manual one instead. Most insurances will only cover a powered wheelchair every 10 years but a manual one every 5 years. Additionally, people with cognitive disabilities often do not possess the fine motor skills or reaction time needed to drive a powered wheelchair, and therefore, using one can be dangerous. There are devices on the market that motorize manual wheelchairs, but they are controlled by the wheelchair user, and therefore, are subjected to the same requirements for cognitive ability. My design is different because it is retrofittable to what people already use, less expensive than a new wheelchair, and controlled by the caregiver.

Future plans

I am planning to condense the electronics and continue refining the motor system to improve efficiency and reliability. Then, the design would need to undergo hours of testing to ensure that it is reliable and safe to use long-term. I would like to give some to my aunt’s friend and other users I spoke to during my research. This will help me test that the final product is user-friendly, portable, and solves their needs. I want this product to be affordable so that users won’t need to deal with insurance, and therefore, I plan to explore manufacturing options to reduce costs without compromising quality.

Awards