4 1 Ultrasonic Sensor How an Ultrasonic Range

4. 1 Ultrasonic Sensor How an Ultrasonic Range Finder works

4. 1 Ultrasonic Sensor • Ultrasonic Range Finder • New. Ping Library • DC Motor Application

4. 1 Ultrasonic Sensor • The sensor releases out an ultrasonic frequency every few milliseconds • The sensor then waits to hear for the reflected frequency • The time it takes for the sensor to send the pulse and receive it back again is how the distance is calculated • Infrared Sensors also work in the same principle of “Time of Flight”

4. 1 Ultrasonic Sensor Wall

4. 1 Ultrasonic Sensor • An ultrasonic sensor measures the range from the sensor that are facing perpendicular to it. • Distance = Velocity x Time Distance Velocity Time

4. 1 HC-SRF 04 Echo Output Trigger Input

4. 1 HC-SRF 04 • The sensor sets an 8 cycle burst of 40 KHz of Ultrasound • Waits for an Echo to be sent back from a distant object • Range is calculated through the time interval between sending trigger signal and receiving echo signal. Infrasound - 20 Hz Acoustic 20 Hz - 20 k. Hz Ultrasound 20 k. Hz - 2 MHz +

4. 1 Breadboard Diagram – US Sensor Hardware: Ultrasonic Sensor A Flat Object

4. 1 Ultrasonic Sensor Testing • After you wired up the schematic properly you should be getting values returned in Centimeters.

4. 1 Ultrasonic Sensor Adding Haptic Feedback with Motors

4. 1 Ultrasonic Sensor Testing • We will now add motors to give a vibrational feedback that will represent the given range from the ultrasonic sensor.

4. 1 Breadboard Diagram - Haptic Feedback Hardware: DC Motor Diode Transistor Resistor