Testing the constancy of the target axis with a change in focusing in precise theodolites and electronic tacheometers

The obtained measurement results show that for short targets of a few metres long, position changes of the target axis are considerable and even come close to lc (TC1610). Even in the case of the telescopes of precise T 2002 theodolites geared for close object measurements, target axis vacillations almost amount to 40cc. The course of vertical changes in the target axis vacillations is quite distinctive/typical/unusual/interesting? For all tested instruments the character of these changes was very similar. It is a phenomenon which is difficult to explain in a clear fashion. It should be also noted that the greatest changes take place with short targets up to about 10 m. Vacillations of the target axis above this length are considerably smaller and generally do not exceed 10cc. Although target axis movements expressed in terms of angular units are significant, their influence on accurate location of a point position is slight and does not exceed (especially for the horizontal component) a few hundredths millimeters. In spite of this changes in the target axis should be taken into consideration in designing high precision angular measurements for small objects

Investigation of stability of precise geodetic instruments used in deformation monitoring

Monitoring systems using automated electronic total stations are an important element of safety control of many engineering objects. In order to ensure the appropriate credibility of acquired data, it is necessary that instruments (total stations in most of the cases) used for measurements meet requirements of measurement accuracy, as well as the stability of instrument axis system geometry. With regards to the above, it is expedient to conduct quality control of data acquired using electronic total stations in the context of performed measurement procedures. This paper presents results of research conducted at the Faculty of Geodesy and Cartography at Warsaw University of Technology investigating the stability of “basic” error values (collimation, zero location for V circle, inclination), for two types of automatic total stations: TDA 5005 and TCRP 1201+. Research provided also information concerning the influence of temperature changes upon the stability of investigated instrument’s optical parameters. Results are presented in graphical analytic technique. Final conclusions propose methods, which allow avoiding negative results of measuring tool-set geometry changes during conducting precise deformation monitoring measurements

Monitoring of the wut grand hall roof in conditions of high temerature changes

Geodetic control measurements of changes in geometry an object should satisfy high accuracy and reliability. New techeometers equipped with Automatic Target Recognition automatically moves the telescope to the prism and supports control point measurements. The accuracy of using an ATR system and the stability of an instrument in precise measurements were present the results of monitoring measurement were controlled in laboratory and field conditions. This paper will present the results of monitoring measurements with a Leica TDA 5005 during the investigations of roof geometry in conditions of high temperature changes

Investigation of practical and theoretical accuracy of wireless indoor positioning system Ubisense

This paper presents the accuracy investigation results and functionality of Ubisense RTLS positioning system. Three kinds of studies were conducted: test of calibration accuracy, analysis of theoretical accuracy of the coordinates determination as well as accuracy measurements in field conditions. Test of calibration accuracy was made with several different geometric constellation of reference points (tag positions). We determined changes of orientation parameters of receivers and disturbance of positioning points coordinates against chosen reference points constellations. Analysis of theoretical accuracy was made for several receivers spatial positions and their orientations. It allowed to indicate favourable and unfavourable measurement area considering accuracy and reliability. Real positioning accuracy of the Ubisense system was determined by comparison with coordinates measured using precise tacheometer TCRP1201+. Results of conducted experiments and accuracy analysis of test measurement were presented in figures and diagrams

Investigation of short-term roof structure deformations using geodetic methods

The article contains the results of the measurements of the Warsaw University of Technology Main Hall roof deformations under various conditions. These results were obtained autornatically using precise motorized tacheometres TDA5005 and TCRP2002. In this work we compare the vertical components obtained with tacheometric measurements to the results of geometric leveling for chosen control points. The aim of this research was the assessment of the usefulness of the proposed monitoring method to determine structural deformations

Accuracy analysis of a wireless indoor positioning system using geodetic methods

Ubisense RTLS is one of the Indoor positioning systems using an Ultra Wide Band. AOA and TDOA methods are used as a principle of positioning. The accuracy of positioning depends primarily on the accuracy of determined angles and distance differences. The paper presents the results of accuracy research which includes a theoretical accuracy prediction and a practical test. Theoretical accuracy was calculated for two variants of system components geometry, assuming the parameters declared by the system manufacturer. Total station measurements were taken as a reference during the practical test. The results of the analysis are presented in a graphical form. A sample implementation (MagMaster) developed by Globema is presented in the final part of the paper