Project objectives

Geodetic reference frames form the backbone of all georeferencing services. In order to compare global measurement data for observations such as sea level monitoring an uncertainty of 1 mm or better is required, significantly below the current capability of 4 mm. This project focuses on two critical points within what is a complex traceability chain. Firstly, references of unprecedented accuracy for the Earth-bound verification of space-geodetic methods like Satellite Laser Ranging (SLR) or Global Navigation Satellite Systems (GNSS) are established. Secondly, the surveying capabilities for the geometric tie of co-located space-geodetic observations are systematically improved. Innovative field instrumentation and novel analysis strategies will thus be developed.

Funding

This project 18SIB01 GeoMetre (Large-Scale Dimensional Measurements for Geodesy) has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme (DOI: 10.13039/100014132).

Large-scale dimensional measurements for geodesy

Project objectives

The overall objective of this project is to improve the complex traceability chain in geodetic length metrology. The specific objectives of the project are:

To develop and validate field-capable primary or transfer standards to disseminate the unit metre over reference baselines over distances of at least 5 km with a measurement uncertainty below 1 mm (k = 2).
To develop and validate 3D capable novel measurement devices with a measurement range of operation of 200 m and accuracies of better than 200 μm outdoors, capable of compensating fast variations of the index of refraction at a relative uncertainty level better than 1 μm/m.
To develop technologies, methods and uncertainty assessment for the Earth-bound SI-traceable verification of space-geodetic measurement technologies like GNSS or SLR over distances of at least 5 km with uncertainties of 1 mm or better and their implementation in a European reference standard.
To reduce uncertainty of the so-called local tie between co-located space-geodetic techniques at GGOS-CS (and all other eligible sites) by one order of magnitude to 1 mm over 200 m in real time continuous tracking. This requires a coordinated effort of novel dimensional measurement systems, methodology and analysis strategies and their demonstration in pilot studies at 2 European GGOS CS.
To facilitate the take up of the technology and measurement infrastructure developed in the project by the European geodetic measurement infrastructure by provision of European-wide access to the developed high-level references, collaboration with the established existing measurement supply chain (accredited laboratories, instrumentation manufacturers), and dissemination to standards developing organisations (ISO, IAG working groups) and end users (geodesy, surveying, high energy physics, and Earth sciences).

More information are available at the GeoMetre project webpage, https://www.ptb.de/empir2019/geometre/