GENIUS TOY TAIWAN CO. LTD GC258006 Manual De Usuario

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ABOUT ULTRASOUND
Ultrasound is a sound pressure wave that moves through 
substances (gases, liquids, and solids) and has a 
frequency greater than that which humans can hear.
Frequency is simply the number of waves in a given period 
of time. Humans can hear sound waves in the frequency 
range of 20 hertz (which means cycles per second) to 
20,000 hertz (20 kilohertz). 
ANIMAL SONAR
In the natural world, bats, whales, and some birds use 
sound waves to detect objects around them. This is 
especially useful in the darkness of night or underwater, 
where seeing visible light is difficult or impossible.
This type of sensing is called 
echolocation, or biosonar. It 
works like this: The animal emits sound waves that move 
outward in all directions around it. When the sound waves 
hit an object, they bounce off of it and travel back to the 
animal’s ears. The sound waves reach each of the animal’s 
two ears at slightly different times. The animal can 
interpret this time difference to perceive the size, direction 
of movement, and speed of objects.
Animals use echolocation to hunt prey in the dark of 
night. They can also navigate and find their way around 
without normal eyesight.
ACTIVE SONAR
Humans have developed a technology to replicate 
echolocation, which is called 
sonar. Sonar is an acronym 
for 
SOund Navigation And Ranging. Sonar is used for 
navigation in submarines, ships, and airplanes. A similar 
technology using electromagnetic radio waves instead of 
sound waves is called 
radar (RAdio Detection And 
Ranging). 
With sonar and radar, airplane pilots are able to find their 
way and avoid collision with other planes, even in 
complete darkness or in thick clouds. Police use radar to 
detect speeding cars.
Your ultrasonic sensor also sends out sound waves. You 
can’t hear them because they are ultrasonic! One “eye” on 
the sensor head is a transmi+er and the other is a receiver. 
The transmi+er sends out ultrasonic waves, like a 
speaker, and the receiver senses the waves that bounce 
back, like a microphone. In this way, the sensor is able to 
sense objects in front of it, even in the dark.
20 Hz
Low
High
Frequency
20 kHz
2 MHz
200 MHz
Infrasound
Ultrasound
Acoustic
Sound waves of emi!ed call
Echo sound waves
Bat
Dolphin
The ultrasonic 
sensor has one 
transmi+er and 
one receiver.
Submarine
Sound waves sent out
Reflected sound waves
Sound 
transmi!er
and receiver
Object
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ABOUT ULTRASOUND
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