The HC-SR04 ultrasonic sensor uses sonar to determine distance to an object – just like bats or dolphins do.

This module offers excellent range accuracy and stable readings in an easy-to-use package. It operation is not affected by sunlight or black material (although acoustically soft materials like cloth can be difficult to detect). Similar in performance to the SRF005 but with the low-price of a Sharp infrared sensor.

Perfect for collision avoidance on your next robotics or multirotor project!

To buy this please visit http://www.ebay.in/itm/131161110802?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

Module main technical parameters:

1.Working Voltage : 5V(DC)

2.Static current: Less than 2mA.

3.Output signal: Electric frequency signal, high level 5V, low level 0V.

4.Sensor angle: Not more than 15 degrees.

5.Detection distance: 2cm-450cm.

6.High precision: Up to 0.3cm

 7.Input trigger signal: 10us TTL impulse

8.Echo signal : output TTL PWL signal

Mode of connection:

1.VCC

2.trig(T)

3.echo(R)

4.GND

Use method:

Supply module with 5V, the output will be 5V while obstacle in range, or 0V if not.The out pin

 of this module is used as a switching output when anti-theft module, and without the feet when

 ranging modules.

Note : the module should be inserted in the circuit before been power, which avoid producing high level of misoperation;if not, then power again.

 Module Working Principle:

 1.Adopt IO trigger through supplying at least 10us sequence of high level signal.

2.The module automatically send eight 40khz square wave and automatically detect whether receive

 the returning pulse signal.

3.If there is signals returning, through outputting high level and the time of high level

 continuing is the time of that from the ultrasonic transmitting to receiving. Test distance =

 (high level time * sound velocity (340M/S) / 2.

Note : This module is not suitable to connect with electric power, if you need to connect this

 module with electronic power,then let the GND terminal of this module to be connected

 first,otherwise, it will affect the normal work of the module