International Association of Geodesy


SC 4.1: Emerging positioning technologies and GNSS augmentation




SC 4.1

SC 4.2

SC 4.3

SC 4.4


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Terms of Reference

To undertake, promote and report on research that leverages emerging positioning techniques and technologies aiming to address practical and theoretical solutions for positioning, navigation and guidance, including spatio-temporal monitoring and tracking of objects at various scales. The focus will be on multi-sensor cooperative systems operating in adverse GNSS conditions for transportation, personal mobility, industrial and indoor positioning applications and to a lesser extent environmental monitoring. Except GNSS, the primary sensors of interest include inertial and wireless technologies as well as vision-based systems and laser scanning. SC 4.1 will foster linkages and pursue its goal in close collaboration with other IAG Entities, as well as sister scientific and professional organizations, primarily the ISPRS, FIG, ION and IEEE.



Steering Committee

Chair: Vassilis Gikas (Greece)
Vice-Chair: Guenther Retscher (Austria)
Secretary: Harris Perakis (Greece)




Working Groups


WG 4.1.1: Multi-Sensor Systems


Chair: Allison Kealy (Australia)

Vice-Chair: Günther Retscher (Austria)




This group is a joint working group between IAG and FIG.  It focuses on the development of shared resources that extend our understanding of the theory, tools and technologies applicable to the development of multi-sensor systems. It has a major focus on:


·       performance characterization of positioning sensors and technologies that can play a role in augmenting core GNSS capabilities,

·       theoretical and practical evaluation of current algorithms for measurement integration within multi-sensor systems,

·       the development of new measurement integration algorithms based around innovative modeling techniques in other research domains such as machine learning and genetic algorithms, spatial cognition etc.,

·       establishing links between the outcomes of this WG and other IAG and FIG WGs (across the whole period),

·       generating formal parameters that describe the performance of current and emerging positioning technologies that can inform IAG and FIG members.


Specific projects to be undertaken include:

·       international field experiments and workshops on a range of multi sensor systems and technologies.

·       evaluation of UAV capabilities and the increasing role of multi-sensor systems in UAV navigation.

·       Investigation of the role of vision based measurements in improving the navigation performance of multi-sensor systems.

·       development of shared resources to encourage rapid research and advancements internationally.



WG 4.1.2 Indoor Positioning and Navigation


Chair: K. Zhang (Australia)





The needs for indoor positioning and navigation have experienced unprecedented growth in the past decade due to the proliferation and ubiquitous usages of mobile devices and rapid development of internet of things. Location information of people and objects in indoor environments becomes a key issue for many emerging and innovative applications. The primary aims of this working group are:

·        to investigate emerging sensor technologies (e.g. LED, magnetometers), integrated techniques and protocols for indoor positioning and tracking,

·        to discuss, investigate and develop new algorithm and smart solutions, and

·        to bring key researchers and developers in this area together,

·        to disseminate effectively the-state-of-the-art knowledge and new discoveries in the geospatial communities.


Specific projects to be undertaken include:

·        dedicated research projects.

·        dedicated areas of innovative applications (e.g. shopping malls, airports, large industry storages, world exhibition centres).

·        sensors related.



WG 4.1.3 3D Point Cloud based Spatio-temporal Monitoring


Chair: Jens-Andre Paffenholz (Germany)

Vice-Chair: C. Harmening (Austria)





The WG will focus on spatio-temporal monitoring of artificial and natural objects with the aid of 3D point clouds acquired by means of multi-sensor-systems (MSS).  The emphasis will primarily be placed on laser scanning technology and to certain extend on digital cameras.  In general, monitoring applications over a certain period of time require a geo-referencing of the acquired data with respect to a known datum.  Also, a kinematic MSS requires for a referencing to determine the time-dependent seven degrees of freedom (translation, rotation and scale).  Specific objectives of the WG are as follows:

·       performance characterization of laser scanners and cameras and their fusion in MSS with respect to spatio-temporal monitoring of artificial and natural objects in different scales. Potential objects or scenarios can range from plant phenotyping to infrastructure buildings,

·       evaluate the object abstraction for epochal comparison by means of discrete point-wise, areas-based and shape-based approaches. One suitable method to investigate will be B-spline surfaces,

·       investigate and develop suitable algorithms for change tracking over time in 3D point clouds, for instance by means of feature point tracking or shape matching,

·       evaluate the fusion of heterogeneous data like 3D point clouds and ground-based synthetic aperture radar (GB-SAR) data with respect to structural health monitoring applications including infrastructure buildings.

·       algorithms will be implemented in Python, Matlab, C++ whereas for basic 3D point cloud operations open source libraries should be used, such as point cloud library (PCL),

·       establishing links to colleagues from civil and mechanical engineering to benefit from each other in terms of structural health monitoring,

·       establishing working links between this working group and similar national and international working groups such as DVW, ISPRS, IAG and FIG working groups.


Specific projects to be undertaken include:

·       comparative study of different laser scanners in a plant phenotyping scenario in a greenhouse environment. The focus should be on low-cost laser scanners in contrast to high-end triangulation sensors. (link with plant scientists).

·       loading tests of a concrete structures in laboratory environments.

·       simultaneous observations and cross-comparisons using laser scanner, camera and GB-SAR of suitable objects.



WG 4.1.4 Robust Positioning for Urban Traffic


Chair: L. Ruotsalainen (Finland)





The Work Group will focus on the navigation challenges on the urban environments for greener, safer and more comfortable traffic.  At present, navigation is mainly based on the use of Global Navigation Satellite Systems (GNSS), providing good performance in open outdoor environments. However, navigation solution with sufficient accuracy and integrity is needed in urban canyons, where GNSS is significantly degraded or unavailable. For overcoming the aforementioned navigation challenges, research has been very active for decades for finding a suitable set of other methods for augmenting or replacing the use of GNSS in positioning for urban traffic. The Work Group has a major focus on:

§ specification and characterization of the system requirements, especially from the environmental and safety viewpoints,

§ evaluation of the usability of emerging technologies for the urban traffic navigation, including vision-aiding and collaborative driving systems,

§ selection of best set of technologies fulfilling the system requirements,

§ performance analysis of the selected system both for vehicles and pedestrians in urban areas,

§ selecting the most suitable algorithms for map matching and routing.


Specific projects to be undertaken include reporting on and/or establishing links between:

§ the specification and characterization of the system requirements.

§ recommendations on the best set of sensors and technologies to be used.

§ the performance analysis of the selected system.

§ the most suitable algorithms for map matching and routing in urban environments.

the outcomes of this WG and other IAG and FIG WGs, EU COST action SaPPART addressing the satellite positioning performance assessment for road transport, and different actors having interest in urban traffic, e.g. transport authorities, car manufacturers