Adaptive Arm-lifting Attachment for a Standard Walker

The objective of this project is to create an arm lifting device that attaches to a standard rolling walker to provide extra stability and assistance to individuals with ALS that have little to no arm mobility. This design can be customized to suit a wide range of needs outside of ALS.

Materials

• Folding walker with wheels
• Two bass drum foot pedals
• Blue folding walker w/ wheels and arm rests
• PVC pipe

Tools

• Caliper
• 3D Modeling Software and 3D Printer for Prototyping
• Sand paper
• Screwdriver

This step is simply putting together anything that needs to be put together. For us, the blue walker needed to be built.

We used a caliper (as shown in the pictures) to measure the dimensions of the walker. After getting the dimensions, we sketched it out on paper to understand it better.

In this step we 3D scanned the walker so that we could have a 3D model to work with. We started by using a "Peel 3 3D scanner". This was fairly difficult to get a good 3D scan due to the shape of the walker. Eventually we used a Hexagon Absolute Arm to scan it which gave us a better 3D model.

There are also smartphone apps that can 3D scan objects, if you do not have access to the equipment in a lab.

After modeling the pieces that we are attaching to the walker, we printed them using a standard 3D printer.

• Because the base attachment is large, we printed it in three separate pieces. We then first put them together using zip ties to test if it would work, and then we glued them together. You can see it attached to the walker above.
• The red piece next to the foot pedal is there to hold the pedal in place. At first this piece was simply glued onto the slider, but we eventually modeled them together to be one piece
• The silver pieces are used together with a spring to create a rotating joint. (these are the initial prints of the purple pieces in the last pictures)
• The red piece on top of the blue walker is used to connect the arm rest with the walker.
• The other smaller red pieces are used to connect the PVC pipe to the arm rest.
• The first black piece is the platform joint. The arm rest will attach to the top of the platform allowing it to rotate up and down.
• The second black piece is used to attach onto the bar of the foot pedal so there is a place for the PVC pipe to connect.
• The third black piece is our 3D printed ratchet stay which we only made because the racket stay that we ordered ended up getting lost in the mail. We made this piece as a temporary replacement that will be switched out once the ratchet stay is received.

We have uploaded all of our 3D print models below.

After having all attachments printed, we put them all together and attached them to the walker.

• Adjustable link lengths
• Aluminum construction for stability and rigidity
• Rounded edges on all 3D prints
• Metal (or rubber) bottom for the slider piece for sidewalks and outdoor use
• Aluminum tubing to replace PVC tubing