This project involves the use of a single dual axis joystick to control the rotational direction a a servo.
Here, I've used an Arduino Uno as the main processing unit and the Arduino IDE to develop the code.
Let's talk about the servo. It is a negative feedback system. Every time it turns, a signal is fedback to an error amplifier which compares it with the actual signal given to the servo. This error amplifier finds the difference and then feeds it back to the servo to produce the necessary motions to bring the spline or the horn to the correct angle.
A normal servo is also limited to a maximum rotational angle of 180 degrees/half a circle. However, it can be modified to reach 360 degrees/a full circle by hacking the servo. Servo hacking is unfortunately not part of the scope for this post.