Team 3D BAL: Finding Balance for Yoga

For our project this semester, we created products that would assist users that have difficulty balancing when performing various activities. We identified this particular need in the market after a discussion with our mentor, Jenna Fesemyer. During our first visit to DRES, Jenna spoke about a variety of difficulties facing prosthetic users. When she spoke about her enthusiasm for practicing yoga and the difficulties she has balancing in certain poses, we agreed this was something we wanted to pursue. We decided that it would be interesting to find a solution to this challenge because it is a rare and unique opportunity to work on a product that focuses on recreational purposes versus on a daily need. We used the sticky note activity to help hone in on what this opportunity presented.

First, we needed to understand Jenna’s prosthetic leg to understand where the limitations stem from. Her prosthetic has some limitations and does not perfectly mimic an actual human leg. However, it also has some functionality that almost extends the functionality of her prosthetic past that of a sound limb. For example, Jenna’s prosthetic leg has the limitation of having no ankle movement, so the entire leg has to be supported from her residual thigh and microprocessor knee. However, her microprocessor knee has the ability to “lock” in place, so that if she is in a squatting or kneeling position, her knee will lock so that it supports her in that exact position.

To gain a better understanding of the opportunity so that we could design an effective solution, we needed to delve into research before moving ahead. We gained a lot of useful perspective from an ARC yoga instructor, Marsha at Yoga for Amputees, and Jenna herself. From these interviews and discussions, our team was first set on creating a prosthetic foot that Jenna will insert into her microprocessor knee before yoga practice sessions. The initial design included an insertable rod as the main part of the prosthetic and a flipper-like base that would provide Jenna with more support with increased surface area. To visualize the idea, we created a low-fidelity model. As soon as they were created, we met with Jenna to see what her initial thoughts were regarding our prototype. Jenna suggest that we move the rode to the center of the foot rather in the back like a typical leg so that she will have equal support on all sides.

At the same time, we received feedback from Marsha at Yoga for Amputees and she commented that she has seen some prosthetic leg users creating their own DIY “yoga prosthetics”. These users used a base that had more of a “plunger-esque” shape rather than the flipper shape we initially designed. We shared the feedback from Marsha with Jenna and she also confirmed that she believes that a circular base would be the most stable, and having a little suction could provide even more stability when she practices yoga. However, she commented that the suction would have to be weak enough to easily be picked up, as yoga often involves flowing from one position to another. As a result, we created some sketches for a new design based on the feedback.

During this same period, we also met with William, a FUSION 360 expert at MakerLab, and he provided us with sketches that more closely mimics an actual human limb. The sketches created with his assistance had multiple joints that would provide her with more flexibility and movements.

After taking time looking at all of our sketches and low-fidelity models we crafted, we realized that these solutions would only be usable by a small market. A prosthetic replacement could only be used by prosthetic users, which greatly limits the general market of people who have difficulty balancing. The Make-a-Thon introduced us to the residents of Clark Lindsey as potential users and points of inspiration. Thus, during the Make-a-Thon we decided to focus on a more “sandal-eque” product design that will be accessible to a wider range of users in the market versus than just prosthetic limb users that practices yoga. The Clark Lindsey representative that the bathroom is one of the most dangerous rooms in the home regarding falls. Thus, we pictured one scenario that this design could fit in is in bathrooms in front of the sink where elderly people could slip and fall easily and regularly stand for longer periods of time. The design we came up is shown below. We also applied an additional layer of material on the base that provided the shoe with more grip and locks better on to a yoga mat material when practicing yoga.

Soon after Make-a-Thon, we were eager to share and test our product with our mentor. Her reaction to our product was mostly positive as the sandal was able to provide her with more balance than her usual prosthetic. However, the underlying issue was that the sandal could not provide her with any upper calf support. In order to address this, the team decided to abandon our attempt to create a functional product for a larger audience and revert back to our “plunger-esque” prosthetic limb that would cater to specific individual users. Although the target market is smaller, this design could still be very useful for any prosthetic user. This issue is also not being addressed by other designers or companies as we have been able to find through our research, even though there are specific prosthetics for many activities like running and pointe ballet.

We then created a model through FUSION 360 and printed a scaled prototype. Jenna was worried about having that much movement in the “ankle” so we created the file below to print a full scale version for Jenna to test on.

However, when Jenna went to put on the first print, she was not able to insert it into her prosthetic. She realized that the inside of her prosthetic actually was not hollow, and we would need to create a divot for her prosthetic to be able to slide on. We then designed the following file and printed it for her to try out.

Jenna was really happy with the design! The only thing left to do is add some of the cork material that was on the bottom of the additive design to give a touch of height and more traction. We are very happy with the result as well as she said she could definitely feel increased lateral stability and thinks it is a really cool design to have!

You can see our final presentation here.