Considering the pros and cons of the previous 2 ideas for the attachment of the motor housings on the side and on the arm, we came up with a third idea which we are implementing in our final product.
Instead of placing the motor housing directly on the patient’s skin, or by the side of the arm, we have thought of an idea to place the motor housing above the patient’s arm instead. This is done by printing an ‘arch’ support for the motor housing, that goes above the arm as shown in Figure 1. It’s akin to a mini-table for the motor housing to sit on, and the patient’s arm can slot underneath it.
Figure 1: Motor Housing on Arch Support
We decided to choose this design as our final design because:
- It is still relatively portable, and can be shifted from location to location with ease. While it requires a surface to be placed on, when considering that the main aim is for rehabilitation rather than assistive purposes, it is still an acceptable compromise.
- Since the cables are directly above the arm, it mimics natural tendons well.
- Since it doesn’t sit on the patient’s skin, we avoid problems from the weight of the device, such as shear force and sliding, as well as discomfort for the patient.
Summary of Pros and Cons of Motors on Arch Support
| + | - |
|---|---|
| Convenient (relatively portable) | Needs a surface to put on (negligible if considering rehab) |
| Wire routing close to skin, mimics natural tendons | |
| Minimal weight born by the user |
Putting the Components Together 4 – Motor Housing on Arch Support (Chosen Design)