Scooter Prosthetic (Case 05)

Inspiration

The scooter holder design was inspired by existing adaptive technologies and stabilization mechanisms used in pediatric devices. Our primary influence was other bike prosthetics used online, along with prosthetics used with a forearm limb difference.

What it does

The device’s use is to aid our patient riding a bike or scooter. The device has functionality to assist her elbow in bending when gripping a scooter. Also, we included a gripper mimicking the hand to fit the dimensions of small children's bicycle or scooter handles.

How we built it

We first discussed measurement based around what was given. We had a scale of her arm that was being fitted for the prosthetic. We supplemented the measurements we didn’t have with the average measurements of a two year old arm. We used open source designs to base our prosthetic design. Then, we set up a prosthetic unique to what our patients wanted. We documented all the images and research papers used to base our initial design. We also wanted to consider the comfortability of the prosthetic. A common comfortability material used for elbow pads and knee pads is PVA hydrogels to consider as the basis. Divots were created in the prosthetic for that intention. We decided on foam rather than a silicon sleeve. We used CAD to rough prototype. We used reference photos and based CAD models off of the patient's dimensions. The design is simplistic and would have a limited range of motion specific to riding a bike or scooter. We came up with a closed claw design that attaches to the handrail of the bike, however a forearm was needed to hold on to the gripper and attach to the child's elbow. We came up with an upper arm support piece connected to the forearm piece. We also wanted to take a focus on comfortability which is why we wanted to create divots in mind to insert PVA foam pieces to allow it to be a snug fit and for comfortability. Since our recipient likes princesses and purple, we made the prosthetic purple and added princess decals.

Challenges we ran into

One issue we fixed was adding two different parts for the forearm. We wanted to create an extension of the child's upper forearm. Typically for a child her age a forearm starts off wide and then thins out as we move through the arm. We had to break the forearm into two components, the circumference closest to the wrist would slender out like the initial design but for the other component closer to the elbow would have a consistent circumference. We found these calculations in pictures provided and research papers that supplied the missing dimensions. For the hinging process our initial ideas were we had forearm mechanism to upper arm mechanism and a singular screw would hinge the two pieces together and act like a joint but also give the patient range of motion of the elbow. Our initial issue is assembly is inexperience, and learning how to troubleshoot. Also how to piece together components, just a learning curve.

Accomplishments that we're proud of

A breakthrough we had was learning how to rotate our ‘joint’ component in assembly, which was causing major issues as parts would not mate properly. This also led to our discovery of how we wanted the final prosthetic to look like.

What we learned

We learned that combining adaptive prosthetic principles with secure clamping mechanisms allows us to design a safe, adjustable, and comfortable scooter handle bar attachment. We also gained experience in Solidworks design and assembly.

What's next for Scooter Prosthetic (Case 05)

Something we want to consider for future improvement is wrist mobility, if we were to have this we could have the patient clamp on and off the bicycle in an easier fashion. We would want to account for growth and how dimensions at such a young age will change over time, and how we can account for that. It would be nice to create a prosthetic that has longevity.

Built With

• solidworks