Applications of ultrasound

Ultrasounds are sound waves with frequencies higher than the human ear’s highest audible limit. In simple terms, an ultrasound is a sound with a frequency more than (20kHz) or (20,000Hz), i.e., above the maximum audible frequency. Although ultrasound frequencies as high as a few gigahertz can be generated, we are unable to detect them. Ultrasound has a lot in common with audible sound in terms of physical qualities.

To find their prey, animals like bats use echolocation mechanisms based on ultrasounds. Ultrasounds up to (60 – 65kHz) can be detected by animals such as dogs and cats. The dog whistles used by dog trainers generate ultrasounds with a frequency of (23 – 45kHz).

Ultrasound has physical properties that are similar to those of ordinary sound. Bats use a variety of ultrasonic range (echolocation) strategies to identify their prey, and they can detect frequencies as high as (200kHz). Toothed whales, like dolphins, produce ultrasounds that they utilise to traverse the sea and catch prey. Ultrasounds are used in medicine, communication, navigation, testing, cleaning, detection, ranging, and mixing, among other things.

Applications of Ultrasounds

1. Detection of cracks: Cracks in big metallic components used to construct major constructions such as bridges and buildings are detected using ultrasound. A skilled specialist interprets the ultrasonic waves they emit and show, using analytical software to discover and classify defects in the sections of these buildings.
2. Echocardiography: Echocardiography is a procedure that specialists use to examine the health of a patient’s heart. Using the techniques of reflection and detection of ultrasounds from various areas, ultrasonic waves are used to obtain an image of the heart.
3. Cleaning: Spiral tubes and a variety of electronic components in large machinery are difficult to clean. Ultrasonic waves are used in these devices to clean them. The object to be cleaned is immersed in a solution of suitable cleaning material, which is then passed through ultrasonic waves. Dirt and oil detach off the surface as a result of the creation of these high-frequency vibrations.
4. USID: Ultrasound Identification, or USID, is a real-time location system (RTLS). It’s an Indoor Positioning System (IPS) that automatically tracks and identifies the location of objects in real time. Cheap nodes (badges/tags) are affixed to or implanted in objects and devices using this technology. These gadgets send out an ultrasonic signal that is used to communicate their location to microphone sensors.
5. Lithotripsy: People with kidney stones used to have to endure major operations to have them removed, but now, thanks to ultrasonic waves, kidney stones can be broken down non-evasively and without the need for any unnecessary surgery. As a result, high-energy waves travel through the body without inflicting serious injury, shattering the stones into dust or smaller fragments. These fragments can subsequently be passed through the urinary tract and eliminated from the body.
6. Pest control: Many animals can detect sounds in the ultrasonic frequency range that humans can hear. In fact, roaches and rodents have been found to be sensitive to frequencies in the 40 kHz region. This is why “pest controllers” were created to repel pests by emitting loud sounds in that frequency range. Although the findings have not been encouraging, progress is being made.
7. Ultrasonography: Sonograms are the name for ultrasonic images. Medical ultrasounds are diagnostic imaging procedures based on ultrasonic imaging that are commonly used in hospitals. It aids in the detection of the problem area by providing an image of internal body structures such as muscles, joints, and internal organs. It is accomplished by using a probe to deliver ultrasonic pulses to the tissue. Each sound that strikes a tissue reflects, and the sounds that reflect different tissues reflect at different angles, allowing us to distinguish between them. These tissue-generated sound echoes are recorded and displayed in visuals for a professional to examine.
8. Sound Navigation and Ranging: SONAR was created to aid in navigation, detection, and communication beneath the surface of the sea. Sound or ultrasound pulses are sent out, and the time it takes for the pulses to reflect off a distant object and return to the source is measured in this technique. As a result, using SONAR, the specific location of that object can be determined, and its movement may be successfully traced. It aids in the location and tracking of lost ships or aircraft wrecks, submarines submerged, and underwater explosive mines.
9. Echolocation: Echolocation is the method of determining things in space by using sound waves and echoes. Bats use echolocation to move across their environment and find food in the dark. From their mouth and nose, bats create sound waves in the ultrasonic frequency range. These sound waves collide with the things in their environment and reverberate, resulting in echoes. These echoes are subsequently detected by the bats, which aids them in determining the object’s size, shape, and distance. Ultrasonic echolocation is now frequently employed in traffic management applications as well as in the sorting and counting of objects on a manufacturing line.
10. Therapy: Ultrasound has a wide range of therapeutic uses that, when used correctly, can be quite beneficial. Ultrasound is used to break up hard deposits or tissue because of its strong power. This aids in the measurement of tissue’s elastic characteristics and helps to hasten the action of medications in the desired area. Ultrasound is frequently used in research to sort cells or tiny particles.

Limitations of ultrasound

• Increased depth necessitates a lower frequency for efficient imaging. As a result, the resolution is reduced. With the advancement of technology in the United States, some of these machines now utilise the returning second degree harmonic of the original frequency to produce a better image.
• Anisotropy simply indicates that a structure reflects ultrasonography well. Nerves, tendons, and needles are all examples of this. For the ultrasound beam to ‘bounce’ back to the probe and form an image, it must be perpendicular to the structure or close to it. Manufacturers now have a dedicated initiative to improve the image of needles.
• Waves from the ultrasound are blocked by Bone. As a result, as people get older, imaging the spine becomes more challenging.
• Artefacts are a common occurrence. It’s most likely an artefact if a structure can only be observed in one plane. With multi-beam technology, manufacturers have attempted to make life easier. The ultrasound filters away a lot of artefacts by shifting the angle of the ultrasound beam periodically.
• Training: Improved anatomical understanding and a rigorous instructional programme are required for ultrasound procedures.

Conclusion

Ultrasounds are sound waves with frequencies higher than the human ear’s highest audible limit. In simple terms, an ultrasound is a sound with a frequency more than (20 kHz) or (20,000 Hz), i.e., higher than the highest audible frequency. Ultrasounds are used in medicine, communication, navigation, testing, cleaning, detection, ranging, and mixing, among other things.