ROBOARM
The idea behind this project was to create an exoskeleton arm that could aid in the recovery of individuals with muscle injuries (bicep in this case), by taking some or all the load off the muscle. Our group thought such a device could be extremely useful for physical therapy and allow labor workers to go back to work earlier after an injury. We determined our functional requirements should be:
Ability to lift at least 10lbs
Have adjustable padding to accommodate different sized arms
Distribute load to bypass muscle
Powered by an air compressor
Manufactured within a $120 budget
INITIAL PROTOTYPE
We created an initial prototype frame out of foam core board to verify design functionality and adjustability. To determine sizing, we measured an average sized arm for a baseline, and increased the dimensions to allow for padding to be inserted depending on the user's arm size.
AIR POWERED MUSCLES
To act as "muscles", we used bicycle inner tubing wrapped in a braided sleeve to limit the radial and increase axial expansion. A quick disconnect adapter was attached to one end and the other end clamped off. Using this design we were able to expand the tubing 3 inches using just 30psi.
NEW FRAME AND PADDING
For the final prototype, we used metal stock and bolts to create the hinged frame. For the arm supports, we 3D printed the outer portions using a plastic material and used Velcro to adhere the foam padding to the inside.
FINAL PROTOTYPE
To demonstrate the functionality of our final prototype, we attached a 10lb weight to the end and deflated the air powered muscles. As shown, the RoboArm was successful in lifting this weight with minimal assistance from the user. Our design was focused on the bicep for simplicity, but the RoboArm can be adapted to a variety of muscles.
Further Development
In order to make this design more feasible, the next steps in the development of this product would be to design a more portable air compressor. Electrodes could also be used to read muscle stimulation and signal the RoboArm to inflate/deflate, as opposed to the manual release valve.
