Ultrasonic sensors are devices that use the properties of ultrasonic waves. Ultrasonic waves are mechanical waves with frequencies higher than those of audible sound waves. They are produced by vibration of a piezoelectric crystal under electrical stimulation. Ultrasonic waves have high frequency, short wavelength, minimal diffraction, and strong directionality, allowing them to travel in a focused beam. They can penetrate liquids and solids well, even reaching depths of several meters in opaque solids. When ultrasonic waves encounter impurities or boundaries, they produce significant reflections, creating echoes. They also produce the Doppler effect when hitting moving objects. Because of these properties, ultrasonic testing is widely used in industries, defense, and biomedical fields. Ultrasonic sensors, also known as ultrasonic transducers or probes, are devices that produce and receive ultrasonic waves. Let’s look at how ultrasonic sensors are used in both medical and industrial applications.

Medical Applications

Ultrasonic sensors are used in various aspects of production, with medical applications being a major area. In medicine, ultrasound is primarily used for diagnosing diseases and has become an indispensable diagnostic tool in clinical practice. The advantages of ultrasound diagnosis include being painless, non-invasive, simple, clear imaging, and high accuracy, making it popular among healthcare professionals and patients. Ultrasound diagnosis relies on the principle of echo reflection: when ultrasonic waves encounter interfaces between different acoustic impedances in the body, they create reflections. Each reflection appears as an echo on a display screen, with the amplitude of the echo depending on the impedance difference between the interfaces.

Industrial Applications

In industry, ultrasonic sensors are typically used for non-destructive testing of metals, measuring thickness, and monitoring liquid levels. In the past, many technologies were limited by their inability to detect internal defects. The advent of ultrasonic sensors has changed this situation. Ultrasonic testing can detect both surface and internal defects several meters deep. Often, ultrasonic sensors are fixed to various devices and silently detect the required signals.

These sensors are essential for both detecting flaws and measuring critical parameters in medical and industrial applications, demonstrating their versatility and importance.

Basic Principle of Ultrasonic Liquid Level Measurement

The basic principle of ultrasonic liquid level measurement is as follows: An ultrasonic pulse signal emitted by the ultrasonic probe travels through the air. When it encounters the interface between air and liquid, it gets reflected. By calculating the time it takes for the ultrasonic waves to travel to the interface and back, the distance or liquid level height can be determined. Ultrasonic measurement has several advantages over other methods:

• It has no moving mechanical parts and does not come into contact with the liquid being measured, making it a non-contact measurement. This means it is immune to electromagnetic interference and corrosive liquids, resulting in stable performance, high reliability, and long service life.
• It has a short response time, allowing for real-time measurements without delay.

The MB7066 and the ToughSonic-50, are well-suited for use in harsh industrial environments. The MB7066 is a compact yet rugged weather-resistant ultrasonic sensor. It meets the IP67 protection rating, which means it is dust-tight and can withstand brief submersi下on in water. It features high output sound power, continuously adjustable gain, real-time automatic calibration, and excellent noise suppression algorithms, all contributing to accurate, noise-free distance readings. Even in the presence of various acoustic or electronic noise sources, it can provide stable and reliable distance measurements. It can measure distances up to 10 meters, making it ideal for long-distance detection and tank level monitoring.

Ultrasonic Level Sensor MB7066 Product Specifications

• Detection Range: 0-10 meters
• Resolution: 1 cm
• Power Supply Current: 2.1-3.4 mA
• Operating Voltage: 3V-5.5V
• Ultrasonic Frequency: 42 kHz
• Sampling Rate: 10 Hz
• Operating Temperature: -40°C to +65°C (up to +85°C maximum)
• Output Types: Analog output, Pulse width output, RS232 output
• Operating Modes: Free-running mode and external trigger mode

The ToughSonic-50 ultrasonic level sensor has a maximum range of 50 feet (15.2 meters). Like all rugged sensors, it is built for durability and ease of use in harsh industrial environments. The ToughSonic 50 is fully submersible, corrosion-resistant, impact-resistant, and tough. It can be fully configured using SenixVIEW software. The ToughSonic 50 is available in three different housings, each with RS-232 or RS-485 serial interfaces. These 9-wire sensors allow for up to six simultaneous serial, analog, and/or switch outputs. These reliable sensors are used worldwide in remote level applications and tough factory environments.

ToughSonic-50 Ultrasonic Level Sensor Specifications

Maximum Range: 50 feet (15.2 meters)

Optimal Range: 1 foot to 33 feet (30.5 cm to 10 meters)

Temperature: -40°F to 158°F (-40°C to 70°C)

Humidity: 0 to 100% operating

Protection: NEMA-4X, NEMA 6P, IP68

Sensor: Rugged piezoelectric

Compensation: Temperature compensation

Resolution:

Digital: 0.0135 inches (0.3438 mm)

Analog steps: 4099 (0-10VDC), 3279 (4-20mA)

Repeatability: ±0.2% of range at constant temperature, affected by target, distance, and environment

Update Rate: 5Hz (200 ms), adjustable with SenixVIEW; influenced by SenixVIEW filters