On the shaft of each three motors a small mirror is installed. I did it with a plastic gear on the shaft, and glued the mirror to that gear.
Final result will be that the mirrors wiggle a little bit, and that is just what you need to have.
The idea of this construction is to make these figures by giving the 3 motors a specific speed, in order to get a nice figure.
The speed of the three motors can be adjusted by three potentiometers and the Arduino will set the motor speed with PWM outputs.
After finding a nice figure by “playing” with the 3 potentiometers the PWM-values - as shown with the monitor function - can be stored in the Arduino.
By recalling a figure with a selector switches the Arduino will give the three motors the right speed so the figure is presented as before.
The listing of the simple program will show you how it works.