After we finished STEM I around February, we started STEM II, which is an engineering course, taught by Ms. Curran and Mr. Brunner, in which we worked with a client at Seven Hills to build a device that they wanted. We were in groups, and my group received a request about a woman who likes to crochet but has trouble doing so with her disabled right arm. The client is in a wheelchair, and she wanted something that would hold her yarn and stabilize her work.
To solve the problem, we engineered a clamp that could secure itself to the wheelchair and hold our container for the yarn. Because we had issues with communication with the client, it would have been difficult to build a rigid clamp that would fit the client's wheelchair. We created a 3D-printed clamp that could adjust based on the size of the wheelchair. On top of the clamp, we put a plastic container on the sliders to hold the yarn. A slit was cut in the container to allow the yarn to feed smoothly, while the sliders allowed the client to place the bowl where she found comfortable. To the left is our finished product on the wheelchair.
We also built a tray to help our client stabilize her work. We took a generic lunch tray and used a bandsaw to shape it to our needs. We put L bars under the tray to strengthen it and hinges on the side of the tray to allow it to fold over when the client was not using it. The tray was attached to a different clamp that was 3D printed specifically for the tray. We also put Dycem, which is a material with high friction, on top to prevent the client's crochet needles from sliding off the tray. The image on the left is the CAD model of the bowl clamp, while the image on the right is the CAD model of the tray clamp. To replicate this device, you can visit our Instructables page.