This is the third version of the robotic prosthetic arm with an aim to make the arm more dexterous and lightweight.
The primary objective of this version was to create a prototype actuated by micro metal gear DC motors which resembled the anatomy of the human hand in terms of movements and grasping objects. The designing was done with the target to create a lightweight version of the robotic prosthetic arm with precision grip capabilities. The design process was carried out using SolidWorks. The design was then 3D printed on Creality's Ender 3 Pro printer. The micro-controller selected for this prototype was the Arduino UNO.
Each of the fingers were actuated using a micro metal gear DC motor, a rotary potentiometer and a pulley. Nylon wires were passed through the pulley and the fingers to serve as tendons for this hand. When the DC motor rotates, the nylon wire causes the finger to contract. An elastic, flexible cord was used inside the fingers to spring the fingers back into original position of relaxation.
The rotary potentiometer was utilised in order to ensure precision grip of the fingers. As the DC motor rotated, the shaft caused the rotary potentiometer to rotate as well. Arduino UNO was utilised to keep track of the finger position.
The SolidWorks and STL files are available on the repository. Stay tuned for updates on the step-by-step assembly, electrical and programming aspect of this prototype.