Prosthetics are becoming more common in the market today. I recently saw a kid wearing a thanos hand and thought I'd put my old heptics project here. We create a skeleton (metal cut, CAD) and use it mimic a human hand. A simple project but good advance level application of pots I believe.

 

Overview

The project is on creating an artificial arm prototype that mimics the human hand. We use pots at all the joints and as my hand moves the value of the Pot changes resulting in resistance variation which inturn affects the current. This is taken as an analog input on the microcontroller and we go-ahead with adjusting the motor shaft motions of the artificial arm depending upon the current values provided from the human arm. The project is a good experience is exercise your design and basic motion skills, However an improved version of this project was created which is wireless and more accurate and I shall upload it in my account soon.

 

Requirements:

Arduino, Potentiometers, CAD, Metal structures/ 3D printed, motors, a motor driver circuit, basic electronic components like batteries, wires, resistors, etc.

 

Approach:

Haptics (pronounced HAP-tiks) is the science of applying touch (tactile) sensation and control to interaction with computer applications. The pots attached to the human arm vary their resistance depending on the motion of the arm. The analog values act as input for the microcontroller which in turn gives corresponding output signals to the motor driver circuit which controls the motion of the motors of the artificial arm.

 

We use 3 potentiometers for 3 different joints. The three joints are the claws, wrist, and elbow. The Github repository lists these as claws, hand, and base respectively. I chose the word base while coding as the skeleton I made was on a wooden platform and the elbow was attached it.

 

The methodology is as simple as any amount of change in the potentiometer shaft (attached to my arm in the video) is proportional to the amount of motion of the shaft of the motor(artificial arm). This results in the robotic arm imitating the human arm.