STEM II is a course that combines all engineering
skills gathered over the year. Students choose teams of four (or in
some cases, students combine teams) to create an assistive technology
project that could help someone achieve their goals or make daily
life easier. During the course of this project, my team and I learned
about the engineering process, which included the design,
documentation, and presentation of our device. My team, a combination of two teams, was made up of
eight people. My team members were:
Jennifer Shaughnessy, Kweku Akese, Amy Chen, Giang Pham, Omar El
Nesr, Marlon Jost, and McKenna Childs.
We have continued developing the device over the summer, and have filed a provisional patent on the design.
The ability to eat is essential to human survival, but often taken for granted; most individuals do this dozens of times each day. However, conditions such as inclusion body myositis (IBM), an inflammatory muscle disease, can impair motor control and movement, making this daily task incredibly difficult. This results in reduced food intake and malnutrition, reduced social interaction, a lost sense of purpose, and as if the basic right of feeding oneself is taken away (Sarsby, 2020). To help them reclaim this ability and their independence, many technologies have been invented, promising a sense of freedom to those with special needs, but the numerous flaws with these designs make them undesirable or inaccessible. Existing feeding devices range from adaptive utensils to automated robotic arms, yet unaffordability is a primary issue with the majority of options. Highly functional devices are often prohibitively expensive, and cheaper alternatives lack crucial functions required for independent eating. Therefore, effective cheaper devices are required for supporting afflicted individuals.
Our group explored multiple designs during the brainstorming phase, ranging from a cheaper version of the Obi including a rotating plate, to completely new devices. Each team member was tasked with creating a preliminary design concept which was graded on a decision matrix. We created proofs of concepts for each of the three main mechanisms in our device: the elevator, telescope, and spoon mechanism. After using Vex parts and materials such as PVC pipes, we used onShape to 3D print parts for our final design. At first, we had a two-stage telescope and an elevator that moved with a sprocket and belt, but due to stability issues with the elevator and issues with reach for the telescope, our final design included a three-stage telescope and an elevator mechanism that works very similarly to our 3D printers: using threaded rods to "screw" the platform higher and lower on the device.
Overall, our final design consisted of a telescoping arm with a continuous rigged design (for max extension) attached to an upper platform, sliders that hold the upper platform in place, two threaded rods that would be controlled by two stepper motors at the base for up and down movement of the platform supporting the spool and telescoping arm, a Vex motor mounted onto a slab attached to the platform to control the spool that extends the telescoping arm, and a sturdy base plate with a counter weight in the back to hold the robotic device in place during movement. Our final assembly of the robotic device can be seen to the left. In general the device measures 20 x 12 x 24 inches.