More about ultrasonic soundwaves Pro Preview

As the name indicates, ultrasonic sensors measure distance by using ultrasonic waves. One of the “eyes” on the sensor head is the transmitter and emits an ultrasonic wave and the other “eye” is the receiver which receives the wave reflected back from the target. 

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  • #944
  • 17 Aug 2018

Ultrasonic sensors measure the distance to the target by measuring the time between the emission and reception.

How does this happen? The robot emits an ultrasonic wave with a constant speed and uses the Distance-Speed-Time formula that distance is speed multiplied by time (S=V.t). As speed is constant, it is known to the robot. By measuring the time between the emission and reception, the robot finds distance. 


Ultrasonic waves have high frequency – much larger than the frequency human beings can detect.

Ultrasonic sound range and frequencies

Ultrasound is used in medicine and industry.

In medicine ultrasound is used to visualize soft tissue and muscles and thus visualize organs of the body.

In industry ultrasound is used to locate various defects and flaws in production.

When ultrasonic waves are sent to a product, its solid parts reflect them while hollow ones diffract them which makes it easy to locate holes and cracks in concrete, for example.


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