We created a drawing and writing tool for children with cerebral palsy. Our target demographic includes children ranging from those with very limited fine motor control to those who have a higher level of fine motor control and simply need guidance with their movements.
Our goal was to create an assistive drawing and writing tool that gives people with cerebral palsy the freedom to express themselves through artistic creation. To do so, we wanted to create a supportive device that provides a stable, ergonomic experience. The main concept behind the design was to provide resistance to the child's movements to resist involuntary motions. We also wanted to provide guidance to the movements in order to create a relaxing writing and drawing experience. Writing and drawing are very meaningful forms of expression, and we hoped to enable children without fine motor controls to have this experience. The experience of writing and drawing is not only useful when it comes to expressing oneself, but it can also be a very mentally therapeutic experience. By adding a physically therapeutic aspect to the design by helping children to extend their arms, this device is not only relaxing and great for expression, but it can be great for the user's health as well.
Our first attempt was a 2-axis sliding system controlled by the artist’s arm. Attached to the y-axis slider was an ergonomic “mouse” that holds a pencil, pen, or marker. The idea behind this design was to allow users to control the device with their upper arm and forearm. This design, while an effective proof of concept, had several flaws. In an attempt to make the device more portable, we made it clamp to the side of a table. This reduced control and caused the device to fall out of place often. Furthermore, the "mouse" piece was not easy to use for a child with CP. Finally, the device did not give enough support to the arm.
We progressed this initial concept into a more sophisticated control mechanism. In the next iteration we focused on the natural position of an artist’s arm and how it moves when it draws. We found that the arm should sit at a more natural angle and should be able to rotate. We considered the support a child with CP might need and what would be comfortable for a wide range of CP patients.
The first iteration of our tracking system used a two axis sliding system which had a "mouse" shape in the middle and allowed for two degrees of motion. While effective in guiding movement, this design lacked in stability, could not draw curves easily, and forced the arm to sit at an uncomfortable angle. The second iteration was based off of an architectural drawing board. It mounted at the top of the table and allowed movement by bending at joints. By doubling up on the arms, it became very sturdy. However, this idea was trumped by a similar yet better idea which removed the middle joint piece and created a rhombus of arms. These four arms bent at the joints and provided a stable, guided drawing experience in a simple mechanism while easily providing adjustable resistance simply by tightening the joints. This is the idea we decided on.
The hand piece also underwent multiple iterations. First, we had a mouse shaped design which was spring loaded to allow the pencil to touch or hover above the paper. Although comfortable for a completely able-bodied person, for someone with cerebral palsy it would not have been as comfortable. The next design, an arm brace, fixed this problem. By 3D printing a flattened brace and then molding it to an arm, the brace was easily customizable, allowed for increased support, and was more comfortable for children with CP. We made one final improvement to this design by making the length adjustable.