Easy secret knock detector to trigger anything with only an Arduino and a few cheap components

This tutorial guides you through creating a secret knock detector using an Arduino, a piezo transducer, and other components. It covers setting up the circuit, understanding the concept, and implementing the code. The tutorial explains how to differentiate between soft and hard knocks and how to program the Arduino to respond to a correct sequence of knocks. By the end, you'll be able to create a system that performs an action when a secret knock is detected.

What components are needed to set up the secret knock detector circuit?

Explain the purpose of the piezo transducer in the secret knock detector.

Describe how the Arduino processes the taps detected by the piezo transducer.

What is the significance of the secret knock length variable in the code?

What role does the secret counter variable play in the detection process?

Discuss the importance of the setup function in the Arduino code.

What is the purpose of the serial communication in the Arduino sketch?

How does the Arduino differentiate between a soft tap and a hard tap?

How does the code handle an incorrect knock sequence?

What happens when the correct secret knock sequence is entered?