Dr inż. Andrzej Uznański

Analysis of precision and accuracy of point positioning based on NAWGEO service of ASG-EUPOS system

The launching of ASG-EUPOS system in Poland in May 2008 resulted in a significant increase in the use of satellite real-time measurements in surveying. The parameters provided by the GPS/GNSS receiver in the scope of quality of the determined position are mostly unreliable. Moreover, the concepts of precision and accuracy are frequently not distinguished in their meaning and used as synonyms. The paper presents the results of the analysis of precision and accuracy in determining position in Real Time Network measurements using NAWGEO service of ASG-EUPOS system. An important aspect of the applied testing technology was the design of test point location and the use of accurate ground-based measurements for quality control of the reference coordinates of test points, which were calculated from the GPS static measurements. The conclusions from the tests were based on 4475 RTN measurements carried out in 149 test runs on 27 test points. Based on the results of the test measurements, high precision of the determined positions of the points in the RTN measurements was identified. However, their accuracy was significantly lower, particularly for the determined heights of the points. Tendencies were observed to obtain solutions with a few-centimeter biases that limit the possibility ...

Dr inż. Andrzej Uznański

Satellite surveying in construction machine control systems

In recent years there has been a significant increase in engagement in the works associated with the development and modernization of communication in-frastructure in Poland. In the case of road transport, automation of the construction process is increasingly being used to handle the investment. Construction ma-chinery control systems, which generally restrict the participation of a surveyor in the works on the building site, are commonly being used.The paper characterizes the types of construction machine control systems, the types of sensors which are used, and their application related to the machines on which they are mounted. Technological aspects of surveying services for road investments based on satellite surveys have been presented here: static developed in post-processing, Real Time Kinematic GPS and the currently most popular Real Time Network.The achievable accuracy and reliability of the determined position decides about the scope of use of satellite surveys in the construction machine control sys-tems. Taking into consideration the movement of a construction machine, the analysis of the latency influence of the machine body position determined from the satellite surveys in real time on the accuracy of the conducted construction works, gains special importance. These issues have been comprised in the paper. ...