It is harmful that high-power and high-intensity ultrasound continues to act on human tissues. Low power ultrasound is very useful in intermittent action on human tissues. Ultrasound is a kind of vibration mechanical wave. For a popular example, you feel comfortable when someone thumps you on the back, but you feel pain or even hurt when you are hit hard.
The following are from the Internet for reference
Ultrasound is harmless and beneficial to people.
Actually, sound wave belongs to one of the categories of sound, and belongs to mechanical wave. Sound wave refers to a longitudinal wave that can be felt by human ear. Its frequency range is 16Hz-20KHz. When the frequency of sound wave is lower than 16 Hz, it is called infrasound, and when it is higher than 20 KHz, it is called ultrasonic sound wave.
Ultrasound has the following characteristics:
1) Ultrasound can effectively propagate in gases, liquids, solids and solid melts.
2) Ultrasound can transmit very strong energy.
3) Ultrasound can produce reflection, interference, superposition and resonance.
4) When ultrasonic wave propagates in liquid medium, it can produce strong shock and cavitation phenomena at the interface.
Mio's ultrasound power is very small and only needs 5V for power supply.
The ultrasonic module is an electronic module for measuring distance, ranging from 3 cm to 400 cm. It can be used to help the car avoid obstacles or to join other related ranging projects. This module needs to be connected to the motherboard with a yellow identification interface.
L The resolution of ranging is 1 cm, and the measuring distance can reach 400 cm.
_l. Package the file of sensor module library, which is simple and convenient to use.
Support Robo3 Block, suitable for all age users;
1. It is easy to connect with RJ25 interface.
Modular installation, compatible with Lego series;
L is equipped with DIY pin arrangement interface, which is compatible with most Arduino series main control boards.
1. Operating voltage: 5V DC;
L Detection range: 3cm-400cm;
L. Detection angle: within 30 degrees is good;
Size: 52x36x31 mm (long x wide x high);