Effects of Low Temperatures in the Line of Sight of Digital Levels
Publication: Journal of Surveying Engineering
Volume 143, Issue 2
Abstract
Digital levels are high-precision instruments that use bar-code rods and sensitive charged-coupled device (CCD) linear sensors. To determine the height difference, it is necessary to bring the line of sight to the horizontal position. Horizontality of the line of sight is achieved by the compensator. Technical characteristics of the level are checked within the calibration. Level calibration was performed in an accredited laboratory of the University of Belgrade, Faculty of Civil Engineering. However, between two calibrations, the level was used in a variety of conditions and was exposed to different environmental conditions. To check the performance of the entire system (i.e., level, tripod, and rods), an experiment was conducted to calculate calibration curves of the line of sight of three sets of equipment that include three digital levels. The experiment was carried out in cold storage with the temperature ranging from +10°C to –15°C. The results of the conducted experiment are part of this paper and point to the magnitude of the variation of the inclination of the line of sight, effects of relative change in the tripod height, and effects of relative change in the rod length. The obtained results imply that the collimation angle appears as a rod-reading error and can be eliminated by entering the corrections. Values of the accessory corrections (tripod and rod) for the effect of the temperature change indicate that they should be taken into account (corrections must be calculated and entered into the measurement results) in works with high accuracy.
Get full access to this article
View all available purchase options and get full access to this article.
References
Gučević, J., Delčev, S., and Ogrizović, V. (2011). “Determining temperature dependence of collimation error of digital level Leica DNA 03.” FIG Working Week 2011—Bridging the Gap between Cultures, FIG, Copenhagen, Denmark, 1–12.
Howarth, P., and Redgrave, F. (2008). Metrology—In short, 3rd Ed., European Association of National Metrology Institutes, Braunschweig, Germany.
Ingensand, H. (1999). “The evolution of digital levelling techniques—Limitations and new solutions.” The importance of heights, M. Lilje, ed., FIG, Copenhagen, Denmark, 59–68.
ISO. (2002). “Optics and optical instruments—Field procedures for testing geodetic and surveying instruments—Part 2: Levels.” ISO 17123-2:2002, Geneva, Switzerland.
ISO. (2005). “General requirements for the competence of testing and calibration laboratories.” ISO/IEC 17025:2005, Geneva, Switzerland.
Leica. (2006). Leica DNA03/DNA10 User Manual Version 2.0, Heerbrugg, Switzerland.
Mazić, E., Tuno, N., Savšek, S., and Kogoj, D. (2013). “Optimalna dolžina vizure digitalnega nivelirja Leica Geosystems DNA03.” Geodetski Vestnik, 57(2), 233–244.
Takalo, M., and Rouhiainen, P. (2004). “Development of a system calibration comparator for digital levels in Finland.” Nordic J. Surv. Real Estate Res., 1(2), 119–130.
Vodopivec, F., Bogatin, S., and Kogoj, D. (2004). “Ein neuer Komparator für die Kalibrierung von Nivellierlatten auf der Basis eines optischen Encodersystems.” Ingenieurvermessung 2004, 14th Int. Conf. on Engineering Surveying, ETH, Zürich, Switzerland, 331–336.
Wolf, P. (2002). “Surveying and mapping: History, current status, and future projections.” J. Surv. Eng., 79–107.
Woschitz, H., Gassner, G., and Ruland, R. (2007). “SLAC vertical comparator for the calibration of digital levels.” J. Surv. Eng., 144–150.
Information & Authors
Information
Published In
Journal of Surveying Engineering
Volume 143 • Issue 2 • May 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Dec 1, 2015
Accepted: Jul 25, 2016
Published online: Nov 14, 2016
Discussion open until: Apr 14, 2017
Published in print: May 1, 2017
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.