This sound-following 3pi robot uses three Electret microphone breakout boards and two 74HC4052 multiplexers. Here is a video of the robot in action:
For more details, see this thread on the Pololu forum.
Grating-based External Cavity Tunable Laser
Grating-Based External Cavity Tunable Laser,Red Grating Laser,Laser Grating Reflection,Grating Reflector Laser
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