Working Principle of Ultrasonic Sensor

Working Principle of Ultrasonic Sensor

Transmitting Ultrasonic Waves: The transmitting part consists of a transmitter and a transducer. The transducer converts the energy generated when the piezoelectric chip is excited by voltage and vibrates into ultrasonic waves, and the transmitter transmits the generated ultrasonic waves.

Receiving Ultrasonic Waves: The receiving part consists of a transducer and an amplifier circuit. The transducer receives the reflected ultrasonic waves and converts them into electrical signals, which are then processed by the amplifier circuit.

Calculating Distance: By measuring half of the round-trip time of the ultrasonic wave and combining it with the propagation speed of the ultrasonic wave in the air, the distance between the transmitting point and the obstacle can be calculated.

Structure of Ultrasonic Sensor

The main component inside the ultrasonic sensor is the piezoelectric chip, which can transmit ultrasonic waves when stimulated by voltage, and then received by the receiving end. Ultrasonic sensors have a variety of structural forms, including straight probes, oblique probes, surface wave probes, etc.

Application areas of ultrasonic sensors

Guiding the blind and sitting posture correction: Use ultrasonic sensors to detect the distance of obstacles, help visually impaired people walk safely, and remind users to maintain a correct sitting posture.

Automotive electronic ranging: In lane assistance systems, parking assistance systems, brake force assistance systems, and active cruise systems, ultrasonic sensors are used to measure the distance between vehicles and surrounding objects to ensure driving safety.

Advantages and disadvantages of ultrasonic sensors

Advantages

Simple structure, easy manufacturing, and low cost.

It has strong penetration of rain, snow and fog, and can work in bad weather.

It can detect transparent or colored objects, metal or non-metallic objects, solids, liquids and powdery substances.

Disadvantages

The transmission signal and aftershock signal may cover or interfere with the echo signal, resulting in the loss of detection function below a certain distance.

Ultrasonic waves have a certain diffusion angle and can only measure distance, not direction.

In short, ultrasonic sensors play an important role in modern science and technology with their unique advantages and wide application fields.