It’s great to say that we’re finally beginning to see some actual results. A prosthetic hand has been printed, assembled, and attached to our testing rig. The first two rounds of tests on this model have been completed: the activation force and the efficiency at 0° of a bend. Testing will continue throughout this week until we have a baseline standard to base our improvements off of.
We have several possibilities to improve the hand, though some of them are more concrete than others as of now. After a group meeting to look at possible improvements, we focused on 3 key aspects of the design that we could change. First, the pins that attach the pieces of the hand together should be made of metal because the friction between metal and plastic is much less than plastic on plastic, but whether we use dowel pins or machine a similar type of pin is unclear for now. After the first round of testing we will look further into this. Secondly, we need to design a way to adjust the tension of the elastics. There is already a mount for the pull cables, so we might just add a second tier to this mount so it can serve both purposes. Thirdly, we discovered a treatment for abs that drastically smooths its surface. This could greatly improve performance and aesthetics. Acetone vapor is used to partially dissolve the outer layer, giving it the glossy finish. After some more research on this we should be able to give it a try under our fume hood.
Here’s a link to one of the acetone examples we found.