For a course project in a graduate mechatronics class, my team built a robotic arm that follows the motion of a user’s hand. The end effector, the white square shown in the upper right corner of the figure at right, represents the user’s hand. Four servo motors are used to control the position and orientation of the hand. The software was developed in python.
A video demonstrating the arm’s capabilities can be found at this link. An optical sensor detects the position and orientation of the user's hand; that information is conveyed to four servos, which control both the position and orientation of the arm. The arm is able to replicate the hand’s motion, assuming that the elbow has little translation. While there is lag in the communication and the servos’ strength is limited, the arm is able to replicate motion with frequencies less than 1.5 Hz without noticeable delay.
This work included the following:
1) Serial communication through USB and Bluetooth using UART
2) Servo motor position determination
3) Human interface design and implementation