Reconvertion of 30 years lego bricks

This carterpillar is controlled manually with a standard bluetooth logitech joystick. Automatic mode is under beta test :)

 

Parts :

Raspberry pi

Logitech joystick

2x TIP120 TO-220 Darlington Transistors NPN

2x DV 5V Coil 8 Pins DPDT Power Relay

1 battery of an old mobile

1 mobile external USB battery

1x HC-SR04 Ultrasonic Module

...