Prosthetic armSep 21st, 2020 | by: Gyan Krishna
Category: Electronics Arduino
this is a 3d printed prosthetic arm that uses emg sensors for input. the hand is 3d printed in petg material.
the electronics is controlled by an Arduino Nano, which takes input from a emg sensor that is used to control the fingers.
each finger is controlled by strings connected to a servo motor.
the emg sensor is powered by 5v and gnd from the Arduino and -5v from a 7660 ic.
the Arduino can also take inputs from 6 buttons that are all connected to a single analog pin, by using different voltages for each pin created by a voltage divider.
it also has four modes of operations(manual control of each finger, number signs, some predefined movements, and emg mode), that can be selected by a jumper.
the circuit for it has been designed in easyEDA and since its the first version i wanted to test it in perf board before making a pcb.
the 3d models have been adopted from the inmoov project, while the circuit design and the programming was done completely by me. further improvements include designing the hand on fusion360, adding bluetooth to it so that it can be controlled by an app and some better emg sensors.
few videos of me building and testing it are below
the images attached include the following:-
1. the first image shows the full view of the hand with the top cover open reveling the motors and strings inside.
2. the second images shows the soldering and the wiring on the bottom surface of the pcb
3. the third image shows the pcb outside of the hand and shows the components layout etc.
4. the fourth image is the circuit diagram
top view of the entire hand
bottom surface of pcb
pcb attached on the hand
the circuit diagram