https://cambridge.nuvustudio.com/studios/developing-design-adaptive-devices/arte-para-todos#tab-portfolio

Many people with cerebral palsy have difficulty grasping and accurately controlling writing implements due to their lack of fine motor controls, thus diminishing their ability to draw and write. In many cases, children with cerebral palsy have muscles which are constantly under tension. This is painful and makes fine motor control difficult and even impossible. 

Our solution to this common problem was to create a user-friendly writing aid for children who lack fine motor control, especially those with cerebral palsy. Drawing and writing can be a very mentally rewarding process, and we wanted to give kids without fine motor control the ability to draw and potentially even write. Furthermore, the act of using this tool can be beneficial to users' physical health as it stresses the muscles which are often under tension.

Throughout the process of designing this writing aid, our primary goal was to create an adjustable and comfortable writing and drawing tool for people living with cerebral palsy. We wanted to allow users to select from a variety of mediums, including pencils, pens, markers, etcetera. By securing the user's arm into a brace, we aimed to assist reduce the effects of tremors. Also, this brace would allow the user to use their entire upper body to control the device instead of just their hand. This is useful for users who have gross motor control, but lack fine motor control. Finally, we aimed to provide a physically therapeutic experience to users by stretching out muscles which are often tense in severe cases of cerebral palsy.

Our design was primarily made up of a two dimensional tracking system which guides the movement of the user's arm using a rhombus of steel pipes. The joints between the pipes use rubber washers to provide adjustable resistance. At one end of this tracking system is an arm brace which secures the user's arm. Attached to the arm brace is a hand rest for added comfort and the pencil holder which can secure a wide range of writing utensils. Finally, there is a grip which the user's secondary hand can grasp for added leverage.