Ultra-sonicSensor < AFNOG

---+ The Ultrasonic Distance Sensor HC-SR04

In order to measure the distance of the colored paper sheet from the sensors we use the [[http://www.micropik.com/PDF/HCSR04.pdf][HC-SR04]] ultra-sonic distance sensor.

<img alt="" height="404" src="%ATTACHURL%/hc-sr04.png" width="480" />

As can be seen from the photo, the modules has 4 connections:
   * Vcc, which is 5V
   * Gnd
   * Trig
   * Echo
The module is triggered with a 10us TTL trigger pulse. It then sends an 8 cycle sonic burst of 40 kHz and tries to detect the echo. The module sends an echo pulse whose length is proportional to the time the sound signals takes to the target and back.

These are the connection we make:
| Vcc | 5V |
| Trig | gpio 23 |
| Echo | gpio 24 via the level converter |
| Gnd | Gnd |
 

Here is a Python test program demonstrating the readout:

%ATTACHURL%/hc-sr04.py.txt

-- %USERSIG{UliRaich - 2018-02-08}%

---++ Comments

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Attachments

Topic attachments
I	Attachment	History	Action	Size	Date	Who	Comment
png	hc-sr04.png	r1	manage	172.8 K	2018-03-06 - 13:45	UliRaich
txt	hc-sr04.py.txt	r1	manage	0.9 K	2018-03-06 - 13:59	UliRaich

This topic: AFNOG > WebHome > Ultra-sonicSensor
Topic revision: r4 - 2018-03-08 - UliRaich