For my project, I decided to make a prosthetic hand. Here are all the issues that I have encountered (so far):
2/13/2023: When I 3D-printed the first version of the index finger, the paracord that was supposed to go through it wouldn’t fit. In order to rectify this, I scaled the finger to 110% its original size and reprinted it. It also printed with supports which would be a headache to remove.
3/14/23: One of my servos wasn’t responding, so I was forced to replace it with a similar motor. In theory, it would be possible to test each wire and then the servo separately, but that would take quite a while. In the end, I decided the best course of action would be to swap out all of the wires and the servo just to be safe.
3/22/23: The servos were not turning all the way today. I believe the problem is in the battery. I did some research and the battery was indeed the issue. I used this tutorial to change where the servo gets its power from: https://www.instructables.com/Arduino-How-to-Use-a-Servo-Motor-With-an-External-/
4/2/23: Today I encountered some servo jitters, which appear to be occurring as a result of the servos not receiving enough volts. The stall current draw for the servos I am using is 800 mA, but the maximum mA is around 400 mA. I am still figuring out how to fix this.
4/11/23: Update on the previous problem. Mr. McGowan suggested that I add a decoupling capacitor to my circuit to add an extra ‘oomph’ of energy when the current drops. This did help and the first time I tried it with the capacitor, the motor actually broke my fishing line. The jitters still seem to persist, but they seem to be less frequent. I used this website to choose a capacitor to use: https://electronicsbeliever.com/how-to-select-capacitors/
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