Simple Arm Made With DC Motors

Tools:

- #4 DC motors with gear box

- #1 wheel for the DC motor

- #2 L293D motor driver

- #8 Push buttons

- #8 10k resistors

- #1 9v battery

Note: if you are curious to know how the DC motors work from inside, you may watch this video: https://www.youtube.com/watch?v=LAtPHANEfQo

Step 1: Controlling the Rotation Direction of the DC Motor

Wire your components to the L293D according to these schematic diagrams. H-bridges make you able to control the direction of the current flowing in the circuit, and thus the motor rotation direction. If you want to get further understanding about the working principles of the H-bridges, you may watch this video: https://www.youtube.com/watch?v=Fjo7t_U59tY

Step 2: Making the Body

I've designed and 3D printed a part that can hold a DC motor and be fixed on another motor shaft, so the main motor will be able to rotate the held motor.

I also made a simple design to be cut using the laser cutter on wood as a base. You can make whatever base you want, even using a sheet of cardboard and scissors.

Step 3: Putting Everything Together