ULTRASONIC RANGE DETECTOR project

The Ultrasonic range meter detects a reflected wave from the object after sending out an ultrasonic pulse. By measuring the time which returns after emitting a sound wave, a distance to the object is measured. This range meter uses the ultrasonic frequency of about 40 kHz. The way of measuring measures the time which the ultrasonic returns from the measurement object. The transmission period of the ultrasonic is controlled using timer. All of those controls are done by the software of PIC16F873. When using the capture feature of PIC, this circuit is not indispensable. The sound wave propagation speed in air is changed by the temperature. At 0 deg., it is 331.5 m per sec. At 40 deg., it is 355.5m per sec. From the time measured, the distance of the object can be calculated using the relation between speed and distance. We make use of ultrasonic sensors to perform distance measurement. This sensor separates into the two kinds for the transmitter and the receiver. In this measurement the range of the Ultrasonic Range Detector can be increased to find many applications in various fields