Impact of Vial Bubble on the Accuracy of Positions in the GNSS-RTK Mode

Abstract

The use of the GNSS devices in the RTK mode involves taking a vertical position using a circular spirit vial bubble located on the rod. Since the market of geodetic instruments, accessories and software is growing, the authors of this paper performed measurements with the GNSS devices in the RTK mode to determine and demonstrate the impact of the position of the central vial bubble (level) on coordinate accuracy. Measurements were performed on the same rod in the RTK permanent stations network. Instruments of different manufacturers and generations were used in the experiment. Newer generations of the GNSS devices are equipped with special sensors for measuring the inclination of the receiver and eliminating this error. Devices that do not have a sensor give measuring coordinates that are loaded with error. The error is random and cannot be measured. The subject of the analysis of this paper is the magnitude and impact of the error caused by the non-verticality of the rod on which the GNSS-RTK antenna is mounted. The authors experimentally determined that the bubble of the central level has the influence on the accuracy of the position, made conclusions and recommendations for reducing or eliminating the error of non-verticality of the pole.

Keywords

• GNSS
• pole
• position accuracy
• vial bubble