Ultrasonic Sensors FAQ-2

Q: How do ultrasonic sensors handle noise and interference?

Any acoustic noise at the frequency an ultrasonic sensor receives can interfere with the output of that sensor. This includes high-pitched noise, such as the sound produced by a whistle, the hiss of a safety valve, compressed air, or pneumatics. If you put two ultrasonic sensors of the same frequency together, there will be acoustic crosstalk. Another type of noise, electrical noise, is not unique to ultrasonic sensors.

Q: What environmental conditions affect ultrasonic sensors?

Temperature fluctuations affect the speed of ultrasonic sensor sound waves. As temperature increases, the speed of sound waves increases. Although the target may not have moved, the sensor feels that the target is closer. Airflow caused by pneumatic equipment or fans may also deflect or disrupt the path of the ultrasonic waves. This can cause the sensor to not identify the correct location of the target.

Q: What is the best way to detect randomly placed objects using ultrasonic waves?

Teach the sensor the background as a good condition. By teaching the ultrasonic reflecting background surface as a good condition, any object between the sensor and the background will be detected, causing the output to switch.