An ultrasonic sensors (or ultrasound transducer) is a device which works on a similar principle to radar or sonar to evaluate attributes of a target by interpreting echoes from radio or sound waves, respectively. Ultrasound sensors generate high-frequency sound waves and evaluate the echo which is received back by the sensor. Sensors calculate the time interval between sending the signal and receiving the echo to determine the distance to an object. This type of technology was used in the Park to keep track of the number of Dinosaurs, and to locate them if needed. However, the system was debunked when it was discovered that the dinosaurs were reproducing and even escaping without the knowledge of the park staff.