Personal Project: The Hand

The human hand is remarkable. It can make 27 unique movements and has the tactile ability to enable the human brain to perceive the shape, size and texture of objects without seeing them. While we might take our hands for granted, they are essential for human interaction with the world. This is a key reason why robotics engineers have spent decades studying the human hand and trying to replicate its movements, dexterity, and tactility. My project aims to build on the study of engineering robotic hands by developing a hand that can grasp items without the use of a controller. It simplifies the process of robotic hand movement by allowing a robotic hand to move through the parallel movement of an actual human hand.

         I started my project by researching different reasons why engineers are building robotic hands and what obstacles they face. I learned that a lot of research on robotic hands is done to advance human prosthetics. A major problem today is the expense of creating prosthetic limbs that replicate the wide range of human limb and hand movement. I thought that a way to fix the problem would be to create a robotic hand that could be attached to a prosthetic arm and could mimic actual hand movement by the parallel movement of the functioning opposite hand.

To create my project, I decided I would need to design and build three things. First, I needed to develop a code that would turn the on-screen images of my finger joints into plotted points and then find the angle of them so the mechanical fingers could move. Second, I needed an Arduino that would enable me to push and pull the fingers of my robot using a push pull mechanism that works in tandem with moving my fingers in front of my laptop camera. This meant that both the code and the Arduino would have to communicate with one another. Third, I needed to create a design using CAD and 3D Printing to hold the push pull mechanisms in place so that they would move the phalanges of a robotic hand when I moved my actual hand in front of my laptop camera.

I completed all three elements of the design and building process and my robotic hand now functions as anticipated. However, getting to completion required many modifications to my original idea and a significant change to the overall design of my robotic hand, as I faced numerous obstacles and challenges along the way. The first key challenge was that I was stuck on how I would code the project, and eventually learned about a Python extension called CVZone, which would enable me to plot points on a hand and label them in order to find the angle of them. A second challenge I faced was deciding what to use for the push pull mechanism. A third challenge was figuring out how to link the Python to my Arduino to allow the servos to move when the angle of my fingers changed.          

This project has increased my knowledge of Arduino, Python, CAD, trigonometry, vectors, and the anatomy of the human hand. I learned about the limits of Arduino uno, which has piqued my curiosity to explore how to hook up multiple Arduino units to accommodate more servos. I was able to use trigonometry in an applied context to solve a problem. In terms of next steps, I want to expand this project beyond just a hand and build a robotic arm that functions in conjunction with the robotic hand. This might become my Grade 12 Capstone Project. I want to continue learning about how robotics can facilitate the development of prosthetics.