What is an Ultrasonic sensor ? An Ultrasonic sensor is a device that can detect signals of a specific frequency. Especially, audio signals.
How does it work ?
It sends an audio wave of a specific frequency, then it will raise the output signal HIGH. Once the echo hits the receiver the signal goes LOW.
How does it look like ?
How can we calculate the distance from the obstacle ?
The distance is proportional to the time the output signal is HIGH. Since, the time taken by the audio signal to reach an obstacle and reach back to the sensor is equal to the time the signal is HIGH, we can calculate the distance.
Speed of sound = 340.29 m / s
Signal Up Time = 0.01 s
Distance Travelled = (Signal Up Time) * ( Speed of sound )
This gives us the double distance. since, the audio signal travels from the source to the obstacle and back
Distance To Obstacle = Distance Travelled / 2
What are we going to build ? A Distance calculator to understand the basic setup of an ultrasonic sensor. Later, we will convert it into a human interactable device.
Baisc Setup
Link to the Github project: Ultrasonic HID