Or Arduino|Enhance your Arduino projects with the 5PCS KY-031 Knock Sensor Module, ideal for switch and sensor applications with a robust operating temperature range of -40℃~+80℃.
This is not a cheap version of the $20 commercial motion sensor chime, nor a fancy one. I built this because I have the parts on hand, I enjoy building it, and I learn how to control ultrasonic sensor, relay module and solenoid with Arduino. My office is free to enter for almost an...
Arduino Uno board which act as a microcontroller unit. The Piezo sensor takes the knocking input and then passes it to the Arduino board where the input pattern is compared with the original Secret pattern. In case of wring pattern, the GSM sends an alert to the given Phone Number.R. ...