Mobile Phone Ultrasonic Distance Sensor

Mobile phone ultrasonic distance sensor

1. The ultrasonic wave can be used to detect whether there is an object passing by, which can be realized by continuous distance measurement. There are many ultrasonic driving and receiving circuits and online references, but generally the remote detection effect is not good, and it is OK within 3 meters. The 8-12 meter ultrasonic continuous distance measuring circuit is enough for you to study for a year or two, and all kinds of expenses are enough for buying a private car. It is recommended not to consider it first.

2. The idea of starting a voice system with ultrasonic sensor 2 is not applicable. You can use the signal cable, the infrared tube of the remote controller, and the wireless data transmission radio (this is not expensive, about 200 yuan, it can transmit hundreds of meters, and the RS232 interface). Why do you use ultrasonic? The following problems need to be considered when using ultrasound here: 1. Mutual interference of two kinds of ultrasound (including space echo interference, shell vibration interference, circuit power interference); 2. The directivity of ultrasonic wave is very strong. The deviation is 2-10 degrees, and the signal attenuation is obvious. The farther the ultrasonic wave is, the smaller the effective angle is; 3. Distance problem, the attenuation of ultrasonic wave in air is very large, unless it is necessary to transmit signals in water; 4. Anti interference problem: ultrasonic wave is also a mechanical vibration wave, and it is often generated in the natural environment. The voice speaker activated by ultrasonic wave will not ring with a single knock, right? I'm worried...

Let me give you a suggestion. It's a good idea to use ultrasonic wave to detect whether there is an object passing by. It's almost the best solution within 3 meters; Another way is to use infrared tubes, which are the infrared transmitting and receiving tubes of the remote controller. It is also good to put a mirror on the opposite side, or put the transmitting end on the opposite side, but there may be reliability problems under oblique sunlight; Use ultrasonic to drive the speaker. If it is used in the air rather than in the water, it is recommended to consider the infrared tube of the remote control. If it is far away, you can use a wireless data radio.