Ultrasonic Coordinate Meter

A co-operative project between HAAG Elektronische Messgeräte GmbH and Ultrasound Institute

Contract no.: 7603

The objective of the project

To develop ultrasonic system for measurement of the position coordinates of the moving object.

Ultrasound Institute

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Developed system consists of the small size transmitter of ultrasonic waves, fixed to the moving object, two receiving channels, separated by a specified distance 1m and the software for calculation and presentation of the 2 coordinates on PC screen. The transmitter is triggered wirelessly by infrared (IR) transmitter and is radiating 40kHz frequency ultrasonic pulses. These pulses are received by 2 receiving channels and processed by an embedded digital signal processor (DSP). In order to increase a noise robustness and accuracy of system, the transmitter radiates coded sequences, which are processed by the DSP.

Position of the ultrasonic source is determined by the binaural method.

  • Ultrasound propagation times t1 and t2 from the transmitter T to two receivers (R1 and R2) placed at some distance L0 from each other are measured;
  • The coordinates of the transmitter xt, yt can be calculated according:

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Technical parameters

  • Maximal distance 20m;
  • Expected uncertainty of measurement of the x and y coordinates ±7cm;
  • Measurement duration (20m):
    • single measurement mode 5s;
    • averaging mode (10 measurements) 10s;
  • Frequency of ultrasonic waves 40 kHz
  1. R.Kažys, L.Mažeika, O.Tumšys. The experimental investigation of spatial resolution of ultrasonic coordinate meter. Ultragarsas. 2002. Vol. 42. No. 1. P. 29-31. /pdf/
  2. R. Kažys, L. Mažeika, O.Tumšys. Ultrasonic method for measurement of mobile object coordinates. Ultragarsas. 2008. Vol. 63. No. 4. P. 20-24. /pdf/