Journal of Automation and Control, 2015, Vol. 3, No. 3, 71-74 Available online at http://pubs.sciepub.com/automation/3/3/6 © Science and Education Publishing DOI:10.12691/automation-3-3-6 Distance Measurement via Using of Ultrasonic Sensor Michal Kelemen 1,* , Ivan Virgala 1 , Tatiana Kelemenová 2 , Ľubica Miková 1 , Peter Frankovský 1 , Tomáš Lipták 1 , Milan Lörinc 1 1 Department of Mechatronics, Technical University of Kosice, Faculty of Mechanical Engineering, Kosice, Slovak Republic 2 Department of Biomedical Engineering and Measurement, Technical University of Kosice, Faculty of Mechanical Engineering, Kosice, Slovak Republic *Corresponding author: michal.kelemen@tuke.sk Abstract Paper deals with ultrasonic sensors used for distance measurement. Selected ultrasonic sensor has been tested and results of experiments are shown in the paper. Uncertainty analysis also has been realized. Keywords: ultrasonic, distance measurement, sensor, uncertainty Cite This Article: Michal Kelemen, Ivan Virgala, Tatiana Kelemenová, Ľubica Miková, Peter Frankovský, Tomáš Lipták, and Milan Lörinc, “Distance Measurement via Using of Ultrasonic Sensor.” Journal of Automation and Control, vol. 3, no. 3 (2015): 71-74. doi: 10.12691/automation-3-3-6. 1. Introduction Ultrasonic distance sensors are designed for non- contact distance measurement and these types consist of transmitter and receiver or transceiver which is able to transmit and to receive ultrasonic sound (Figure 1). Main idea is to measure time to fly of ultrasonic sound wave from sensor to detected object. An ultrasonic transmitter sends a sound frequency of above 18 kHz in the air at the speed of 344 meter per second (at 20°C) and the receiver receives the reflected sound from the object. Distance between the transmitter and the object can be calculated by simple calculation by considering the time taken by the ultrasonic wave to travel from transmitter and received back (reflected) by the receiver. Measurement range is up to several meters. Figure 1. Ultrasonic sensor working principle Almost all materials reflect sound waves, so ultrasonic sensors are a fine choice for many tasks. Excellence in the detection and measurement of films, transparent objects, and liquids separate these sensors from their photoelectric counterparts. Target color or frequent color changes also have no effect on ultrasonic sensors. Due to their use of sound waves, ultrasonic sensors also perform well in dusty, dirty environments. However, they do not operate well with small targets against large backgrounds or targets such as foam batting that are excellent for absorbing sound waves [1,2,3,4]. A typical ultrasonic sensor (Figure 2) comprises a clock (signal) generator and a controller to excite the transducer, then a processor and output amplifier to handle the return signal [4]. Figure 2. Ultrasonic sensor block scheme [4] Besides the time of flight principle also they are used physical principles based on Doppler effect and the attenuation of sound waves. Frequently application is as navigation sensor for mobile robots for obstacle avoiding [5]. Figure 3. Ultrasonic sensor on for mobile robot navigation