Laser Show Motor Controller

Here’s a fun idea I had while quarantined during the 2020 pandemic. I have a bunch of these cheap laser modules that can easily be driven from an Arduino with 5V, and they only draw 20mA of current. I also have a handful of cheap vibration motors. What happens when you mount vibration motors on a laser? Well, it turns out you can make a cool laser show!

Here’s what I used:

• Arduino
• SN754410 quad half H-bridge chip
• Laser module from AliExpress
• 2 cell phone vibration motors from AliExpress
• 4 10K pots to control motor speeds, laser PWM duty cycle, and laser PWM frequency

The motors are mounted perpendicular to one another, and when you change the speed of the motors, the vibrations cause the laser to oscillate in chaotic patterns. They look a lot like Lissajous figures you see on an oscilloscope. This makes sense, of course, because the motors cause periodic oscillations along different axes. There are also pots to control the PWM duty cycle and PWM frequency. This leads to even more interesting visualizations.

I made the circuit on an Arduino shield prototyping board. I didn’t say it was pretty.

The code is on GitHub, and I've included the schematic image here so you can build it yourself with the things you have lying around. Have fun!