GNGTS 2017 - 36° Convegno Nazionale

182 GNGTS 2017 S essione 1.2 Linux shell scripts have been written to combine the RTKLIB and BNC features and to redirect GNSS data for simultaneous elaborations. Third parties software called SmartRTK has been adopted to collect LZER0 real-time results and to show them into a geomatic environment running on an Android Tablet (Fig. 2). As we have the full control of the FReDNet RTK engine (Zuliani et al., 2018) we created specific RTK access points (called mount-points) to be used with LZER0 in real-time. The mount-points are VRASP0, VRASP1, VRASP2 and VRASP4, which enable 4 different VRS at various distances from the rover (0 km, 1 km, 2 km, 3 km and 4 km). Currently we are testing the device on the National benchmark network called IGM95 maintained by the Istituto Geografico Militare IGM (https://www.igmi.org/ ). The coordinates of some regional (Friuli Venezia Giulia) benchmarks are measured with LZER0 both in real- time (with VRASP0 mount-point) and with post-processed data. Part of the tests (two of them) are made with a student of the “Istituto Tecnico I.T.G. G. Marinoni” high school of Udine included inside the Italian national teaching program “Progetto Formativo Alternanza Scuola Lavoro” for the year 2017. The results are encouraging (Tabs. 1 and 2) and differences between the known official coordinates and the results from LZER0 are within some centimeters even in post-processing with a Master station more than 5 km faraway. Fig. 2 - Different prototypes have been assembled before LZER0: LONE based on a raspberry Pi B+ and a NVS GNSS receivers (top left), 2 naked LZER0 versions (bottom right). All of them have been used to project the final version of LZER0 (bottom right, the circuitry included inside the white rounded box). LZER0 has been developed with the SoluTOP Company. SoluTOP has modified its geomatic software SmartRTK to include LZER0 as a real-time positioning source. Tab. 1 - IGM 025705 in Campoformido (UD) is an IGM benchmark used as references for the first LZER0 test. The Reference Frame used is ETRF2000 (2008.0), plane coordinates are UTM 33 and the quote is the ellipsoidal height of the benchmark. Differences between the reference coordinates and the LZER0 results (both post-processing mode and real-time RTK) are taken into account. LZER0 RTK coordinates are the average of 5 measures; each of them is taken after the reboot of the RTKLIB module RTKRCV. LZER0 POST-PROC coordinates are the result of a post-processing procedure performed with the Topcon Tools Ver.8.2.3. The Master station is CODR 14 km faraway and belonging to FReDNet. For the calculus a 30 min session of GNSS data, sampled at 1 s, has been used. IGM 025705 Campoformido benchmark TYPE NORTH [m] EAST [m] H. ELL. [m] IGM reference 5097336,565 356202,294 120,466 LZER0 POST-PROC. 5097336,578 356202,349 120,543 DIFF. -0.013 -0.055 -0.077 IGM reference 5097336,565 356202,294 120,466 LZER0 RTK (FIX) 5097336,572 356202,327 120,525 DIFF. -0,007 -0,033 -0,059