Ultrasound sensorsUltrasound sensors use a piezoelectric crystal that vibrates at supersonic frequencies (emission crystal).
Thus high frequency sonic impulses are generated which, when they encounter an obstacle, are reflected on a sensor in the shape of an “echo”. A second crystal detects the sonic return wave (reception crystal). Calculating the return time of the echo of the intercepted object the object’s position can be exactly determined. For manufacturing reasons there is an initial dead band where the sensor signal is not significant.
For this reason the distance range of ultrasound sensors never starts from zero, it goes for example from 51 to 965 mm. This type of sensors intercepts any object, regardless of the type of material, reflectance, transparence, different coloring.
Mesautomazione distributes Hyde Park’s range of ultrasound sensors in Italy that are equipped with a thermal compensation sensor for gradual variations between 0°C and 50°C. Many sensors of this type have a high gain calibration selection to make up for the phonoabsorbing materials problem. It is necessary to avoid turbulent air around the sensor (ex. areas with fans) to make measure or interception stable. Since the ultrasound sensor detects the first echo it receives from any object, if an obstacle is in the field of the sensor closest to the object that must be detected, it can give rise to false interventions.
