Using SOLIDWORKS, I designed a robotic hand with wire controlled prehension and elastic retraction. When the wires fed through the fingers are pulled, the palm will close, and when they are released, the elastics will open up the hand again.
Rapid Protoyping: Mk. I - Mk. IV
Using a 3D Printer, I printed out prototypes, iterating on and redesigning each one making small improvements here and there. Shown to the left is Mk. III, which while similar, had some design flaws that didn’t allow for smooth finger motion.
Programming
Using TensorFlow, OpenCV, and Mediapipe, I performed real time hand gesture recognition through classification and communicated with an Arduino Uno Microcontroller. The image to the left shows the Computer Vision system running, and identifying between an open and closed hand.
Robotic Control
The robotic hand control was driven using serial communication between the Computer Vision software and the Arduino, which controlled the HS-422 Servo Motors.
Finger Changes
One thing keeping the previous iteration from perfection was its slightly jagged movement. By increasing the diameter of the joints, I smoothed out the movement, but still had a ways to go until my fingers' movement was completely smooth.
Next Steps
Going into my next phase of iterations I wanted to do 2 things:
Perfect Joint Smoothness
Give the Fingers Another Degree of Freedom
Abduction & Adduction: Adding a Second Degree of Freedom
Once again, heading back to the drawing board, this time I decided to try my hand at something different. If I wanted a robot hand that can truly replicate human hand gestures, I'd need one that can move the same way.
Understanding Movement
When you add another axis of movement, the next concern is figuring out how to let the robot take advantage of it. Having another degree of freedom would've been useless with my current wire setup, because the elastic + fishing wire just didn't allow for the control I needed.
This led me to a 3 wire setup, with the back wire mainly controlling retraction, with both prehension and tilting being controlled by the front 2 wires.
Rapid Prototyping: Mk. VII - Mk. IX
By 3D Printing iteration upon iteration, I could figure out what was wrong with current designs, and fix it instantly. I mostly changed the wire rope pass-through on each part, and made the overall design bigger.
Final Finger Design
Current Design
