Making progress on the writting add-on for the robo hand.
The finger, pen cartridge, cover, and pen holder all assembled.
Our original clasp was not strong enough when we tried pulling on it, so we scaled it up slightly so it would print with more infill and printed at a higher resolution to make sure it would be more consistent.
We've cut the writing finger's wire so as the hand is straightened, the writing finger remains pointed.
We realized that the other fingers would get in the way of drawing with our current design. To solve this, we needed a way to hold all the fingers down aside from the writing finger. The simplest way would be cutting the string pulling that finger down, so the rest of the fingers would still pull down. This would mean losing the functionality of one finger. Instead, we decided to add a clasp to the string. This still requires the use of the other hand, but the user can easily alternate between full hand control and only holding out the writing finger.
We attached a pen using electrical tape and tried writing with it. It didn't work very well, but it was a major improvement over not being able to write at all (with a current-generation robohand). We held down the other fingers during testing as well, and we plan to try the same but with the pen attached to the thumb, side of the hand, and other locations.
Our final clasp design is done. We used Sketch to edit it as a vector, converted it to a DXF in Illustrator, and after laser cutting and testing the design we're extruding it in Rhino so we can print it.
Designing a new add-on to the robo hand so that it can hold a pen.