${fontLinkMarker}
Prosthetist

I have used flexinol wire to control the movement of the fingers, as the wire provides dexterity, strength and flexibility. Furthermore this type of wire is affordable and easily available within any electronics, fishing or hobby store. The use of the wire to help provide motility helps reduce the overall cost of developing the prosthetic, maintaining within my goal of making the prototype affordable and durable. 


In the image, I am attempting to connect the two ends of the flexinol wire to a servo motor.I had constructed the cardboard fingers our of a cardboard composite, which was internally corrugated ( to provide strength ), However I decided that by running the flexinol wire through the internal corrugation I would be able to effectively control the movement of the fingers. As a result I designed a finger that would enable me to internally run the wire from one end to another and these two ends were then attached to a servo motor. Initially these wires were attached to a wheel mounted on the motor, however I then realised that the ratio of string pulled for the downward motion of the finger to the upward motion of the finger was 4:1. Which effectively meant that more string needed to be pulled down for the inward motion of the finger as compared to the upward motion of the finger to return the finger to the original position. I solved this problem by mounting attachments called “horns” onto the servo motors, the horns allowed me to attach the flexinol wire at a ratio of 4:1, as shown in the images. This implementation effectively solved the problem that I was facing. 



Final assembly of model
Final assembly of model
Fourth Prototype: Vertical Frontal View of Hand, Completed
Fourth Prototype: Vertical Frontal View of Hand, Completed
Fourth Prototype: Horizontal Back View of Entire Arm, Completed
Fourth Prototype: Horizontal Back View of Entire Arm, Completed
Fourth Prototype: Vertical Back View of Entire Arm, Completed
Fourth Prototype: Vertical Back View of Entire Arm, Completed
Fourth Prototype: Horizontal Back View of Entire Arm, Completed
Fourth Prototype: Horizontal Back View of Entire Arm, Completed
Fourth Prototype: Horizontal Frontal View of Entire Arm, Completed
Fourth Prototype: Horizontal Frontal View of Entire Arm, Completed
Third Prototype: Vertical Frontal View of Hand, Completed
Third Prototype: Vertical Frontal View of Hand, Completed
Third Prototype: Vertical Back View of Hand, Completed
Third Prototype: Vertical Back View of Hand, Completed
Second Prototype: Vertical Frontal View of Hand, Final Version
Second Prototype: Vertical Frontal View of Hand, Final Version
Second Prototype: View of Fingers, Completed
Second Prototype: View of Fingers, Completed
Second Prototype: View of Fingers, Uncompleted
Second Prototype: View of Fingers, Uncompleted
Second Prototype: Horizontal Frontal View of Hand, Completed
Second Prototype: Horizontal Frontal View of Hand, Completed
Second Prototype: Vertical Back View of Hand, Completed
Second Prototype: Vertical Back View of Hand, Completed
Second Prototype: Vertical Back View of Hand, Uncompleted
Second Prototype: Vertical Back View of Hand, Uncompleted
Second Prototype: Horizontal Frontal View of Hand, Uncompleted
Second Prototype: Horizontal Frontal View of Hand, Uncompleted
First Prototype: Vertical Front View of Hand
First Prototype: Vertical Front View of Hand
First Prototype: Underside View of the Hand
First Prototype: Underside View of the Hand
First Prototype: Front Vertical View of the entire Arm
First Prototype: Front Vertical View of the entire Arm