Description Automatic hand sanitizer works. so you need to put your hand in front of the sanitizer machine only and the sanitizer machine will give you the sanitizer in your hand till your hand present at the same location. there is an ultrasonic sensor in the machine which detects your presence there. the ultrasonic sensor has two terminal one is a transmitter and another is a receiver. the transmitter transmits the ultrasonic waves and the receiver receives the signal when it comes back and then it will calculate the distance of the object by the ultrasonic sensor distance calculation formula. then the distance send to the Arduino and there is some database for comparison with the present value and according to the threshold the Arduino will send the command to the water pump. so if there any person put their hand then the water pump gets on and sanitizer release to that hand. and when the person pulls back their hand the sanitizer gets to stop.
