RICERCA ITALIANA     

The geomatics in support of the actions of Government of the territory

Università degli Studi di Bologna

Abstract

The control of the territory from the Public Administration (PA) and of the Local Bodies, both in terms of monitoring and knowledge and management of the territorial data, is a living matter in an epoch where information are acquired in greater and greater amount and made available in increasingly short times. Particularly, Geomatica makes available acquisition and handling techniques, specifically addressed to the territory monitoring, to the geographical information updating and to the preservation of the public heritage, that manage data coming both from ground surveys and from aerial and satellite platforms.
Therefore, the research activities scheduled in the project are intended to be a meeting point between the new possibilities offered by Geomatica and the need, from the PA and the Local Bodies appointed to the government of the territory, of knowledge of the Italian territory and of its dynamics. Particularly, the new techniques (real time geodetic precision positioning networks, airborne and terrestrial Laser scanning, remote sensing, high resolution images, Data Base and Geographical Information Systems) supply more and more accurate and sophisticated products that, for a correct characterization of the different problems which they are called on to answer, must be used in an appropriate way and made fully integrated.
A fundamental element for the interoperability of the territorial information, is the possibility to refer them all to the same Reference System; since at the time of the acquisition, data are referred to completely different coordinates and reference systems (cadastral data, GPS positions, satellite remote sensed data) it is necessary to set scientifically correct and computable procedures in order to transform all data to the same Reference System.
A further essential element, especially in a public field, is linked to the definition of standard and to the use of products that can be certified or verified.
Therefore, being a research that includes different aspects of Geomatica and addressed to the interaction between the PA and Geomatica itself, it is important, even though in a synthetic way, to show, for every field, the research lines in a more concrete way.
For a correct three-dimensional description of the territory and of anthropogenic structures, some innovative approaches for the treatment of different kinds of data (airborne and terrestrial laser, GPS/INS, terrestrial and aerial imagery, topographic and cartographic) addressed to the construction of three-dimensional models will develop.
TO
Regarding the connection between different cartographic supports and geodetic systems that different Public Administrations use, it has a practical utility the transformation from cadastral coordinates to Gauss coordinates, in the most appropriate realizations. One of main purpose should be the analysis of transformation process for the cadastral mapping into the WGS84 global system. In this context, we shall care to devise new surveying outlines, relaying upon a cadastre based on GNSS, in addition to what is prescribed on the circ. II/88.
In the framework of the integrated use different data, the research project intends to analyze and to define procedures (sensorweb) for the acquisition and integration of data from sensors placed on aerial and satellite platforms as well distributed in networks on the ground. The management of the whole geographic information is performed by a Web-based software system able to maximize the information extracted from remotely sensed data and to provide a really user oriented interface.
In the monitoring context the aim is to understand costs and benefits connected to the possibility of monitoring, with precision and in a continuous way, buildings or structures subject to movement risk, through GNSS receivers. The methods must be not expensive in order to allow a widespred use. Besides, the possibility of an integrated management between the monitoring on buildings at risk and data for real time precision positioning service will be verified.
Other aspect concerns the management of a so wide amount of territorial information, with different scales and precisions, that should be managed in a correct way, with the purpose not to lose information. The storage and management regarding also the temporal evolution of the territory will be realized through a GIS for the land monitoring that allows to know and govern the evolution in the course of the time of peculiar characteristics, such as cultivations, vegetation or other, or the damages suffered by the territory, with a multitemporal approach.
Finally, regarding the aspect linked to the certification, especially in the frame of the GNSS networks for the real time positioning, it is important to identify procedures that allow the user to certify his own survey, also through the certification of the aforementioned networks. <<<

Principal Investigator

Maurizio Barbarella Università degli Studi di BOLOGNA

Research Objectives

The scope of this research is to realise procedure and products that can be used by Authorities involved in the territory management. The definition of corrected standard procedure, tools and the definition of instrument for the certification of real time positioning services will help the Authorities in the knowledge and management of the territory. These results will be obtained by the investigation of some of the innovative aspects concerning the Geomatic such as Geodetic Network for precise real time positioning, Laser scanning, Remote sensor, Data Base and GIS.
Scecific objectives that play together for the main goal are followed explained:

INTEROPERABILITY BETWEE REFERENCE FRAMES
The final scope of our project is t conceive rigorous procedure for transformations from cadastral coordinates to Gauss’ ones as referred to Roma 40 and WGS84 systems.
We foresee to make up a software proper to the said aim, starting from coordinates and maps in raster or vector type.

LOW COST GNSS EXPERIMENTATION FOR THE BUILDINGS MONITORING
The research try to realise geodetic network constitute by a reference GNSS receiver located in a stable structure and more GNSS low cost receivers in some buildings over a unstable area. All the acquired data by all the receivers will be collected in a Local control centre for the real time processing and archiving. In this way we can monitor the positions of all the buildings in real time respect to the stable one. In order to improve the performances of the system, removing noise and multipath effects, many procedure based on filtering will be set up. These procedure could be useful to reach the desired accuracies and precision also using low cost receivers. At the and a particular study will be performs in order to define some risk alarm levels.

EXPERIMENTATION AND USE OF NETWORK FOR REAL TIME POSITIONING FOR CADASTRAL APPLICATION
Moreover, we shall test a possible usage for cadastral surveying of different (as to accuracy and cost) classes of GPS receivers.
We shall pay a special attention to single frequency receivers: as they have a lower cost, if compared to geodetic ones, a large diffusion may be envisaged among cadastral technicians(TO)

AUTOMATED TOOLS FOR “3D CADASTRE”
The aim of this research is to develop some innovative approaches for the treatment of different kinds of data (laser from air and land, GPS/INS, terrestrial and aerial imagery, topographic and cartographic) for the construction of three-dimensional models of buildings.
Particularly, in the research will be development algorithms for the automatic modelling of buildings’ roofs starting from ALS data (Airborne Laser Scanning) or aerial photogrammetry; calibration procedures for integrated system GPS-INS and digital cameras; image-processing alghoritms for the automatic recognition of homologues geometric entities in two or more frames in order to recover the camera station positions; methods for absolute orientation of models and for direct orientation by means of GPS/INS system. Finally all the algorithm and the described methods will be applied on real test cases.

EXPERIMENTATION OF NRTK NETWORK FOR MONITORING
In order to reduce the cost of building monitoring derived by the establishment of a Local Control Centre for each area under monitoring, the proponent would try to use the already operative Network for precise real time positioning also for the management of this aspect. In this way authorities can dispose of a unique control centre both for real time positioning services and for building monitoring reducing cost in term of human resources and hardware. Furthermore if the reference station located in each stable areas closed to the building to be monitored is a dual frequency geodetic receiver, this station can play a very important rule not only as reference station for the monitoring but also to improve the performance of the models produced by the control centre for real time precise positioning.

NRTK CERTIFICATION
The reserch involved in this subject intend produce a manual of quality for the realisation and for the distribution of the products for real time and post processing precise positioning.
Will be assumed as general model the ISO9001 for the certification of the quality.
The realisation of this product will not be the end of the work but will be a base reference that can be use by the Authorities for the realisation of certified product in this field application.

STUDY OF INFORMATION SYSTEMS THAT INTEGRATE INFORMATION LAND, CARTOGRAPHIC DATA AND DATA FROM REMOTE SENSING
-Implementation of an Geographical Information System for the monitoring of crops in an area Emilia-Romagna, which will study the evolution in time of the characteristics of the crops. The research provides deepening in the study of spectral signatures of major crops, in the area concerned and of the parameters which influence (state of health, phonological stage, coverage leaf).
-Study and implementation of a prototype of Web GIS to experiment with the procedures and the possibility of integration of data from different networks of sensors at the ground in a knowledge basis provided by General maps (base and thematic) and data products to monitor risk situations or warning. <<<

First Results

U.O. BOLOGNA
The results are expected on the following topics:
1.Experimentation on low cost systems for buildings monitoring.
Making of a testing network made of three-four test points for real-time control on the relative movement of buildings located in landslide area.
Running continuous measurement and data acquisition for at least six months.
Proposal of procedures for data analysis and reduction of noise measurement.
2.Experimentation on NRTK networks for monitoring.
Study on integration of monitoring subnets in a NRTK structure. Using the R3 network: project feasibility, prototype [Action influenced by the continuing availability of System Manager R3]
3.Software making
Realization of a software for the analysis of obstacles to the visibility of various constellations of satellites, including Galileo, urban field; data validation of Operational Unit Napoli
Production of tools for the analysis of time series acquired from network monitoring in order to remove the effects of noise able to mask the presence of any movements.
4.Information System intended to monitor culture in an area of Emilia-Romagna,
Implementation of Information System.
Multi-temporal analysis through ASTER image.
5.Evaluation and analysis of natural disasters of different kind through remote sensing

U.O. NAPOLI
-Development of algorithms for the automatic modelling of buildings’ roofs starting from ALS data (Airborne Laser Scanning) or aerial photogrammetry;
-Production of 3-D models for the study of satellite visibility;
-Development of calibration procedures for integrated system GPS-INS and digital cameras.
-Development of image-processing alghoritms for the automatic recognition of homologues geometric entities in two or more frames in order to recover the camera station positions.
-Development of methods for absolute orientation of models and for direct orientation by means of GPS/INS system;
-Application of the methods described on real test cases.

U.O. VENEZIA
Starting from a practical application case, the prototype and its component procedures are intended to be a model applicable to other contexts and territorial and environmental issues, putting as fixed points the use of standard and interoperability.
Procedures must therefore be understood as a working step that starting from the acquisition of data from sensors will allow to analyze the value added derived from the data integration leading up to the production of information "useful", geared to different types of players involved in the processes of government land.

U.O. TORINO
One of the expected results of our project should be analysis, making up and testing of transformation procedures into a global reference system for cadastral mapping, in order to achieve a proper compatibility with GNSS positioning
Obviously, present survey techniques are different from those described by the circ. N. 2/1988 of Italian Catasto. For instance, GNSS receivers use RTK positioning services, which supply centimetrical accuracy in real-time: Italian regional governments are developing such works with new equipments now or in the near future.
GNSS modernization, especially new L2c code, should give decimetrical accuracy with low-cost receivers. A great advantage may also be envisaged with the use of phase-correction WAAS systems, specially for quick surveying. Single frequency with RTK option and WAAS Omnistar Racal Systems, with phase measurements, are available with an adequate accuracy to the cadastral surveying, even without ambiguity fixing
Cadastral mapping in a unique reference system would allow to determine the control points using the more innovative GNSS techniques. These control points are a legal requirements but overall a fundamental fact for all traditional surveying operators.
We hope that future results of our work will prove very fruitful for private surveyors, as well as for the Agenzia del Territorio (Cadastral Agency).

U.O. CAGLIARI
The main research result will be the implementation of a quality manual EN ISO 9001 compliance on the NRTK GNSS networks. The model will described in the Quality Manual compiled during the study.
Are also research products:
-all the reports, redacted during the Do phase, describing the processes identified inside the experimental GNSS network
-all the routines written to manage the monitoring processes dealing to the final products and to the network management
-the results of the surveys submitted to all interested parties and of the meetings with the possible customers: regional and national agencies, users of different networks, instrumentation manufacturers, permanent station network managers.
The fulfillment of this final product will not be an ending point, but will form a foundation usable to build quality plans on a national basis in order to obtain the ISO 9001 certification on the services provided by GPS permanent networks. The ISO 9001 certification on a product’s conformity to specifications is a guarantee for customers on the quality of the provided services and the level of satisfaction of the needs of customers. Through this it is possible to set quality benchmarks allowing to assess the obtained quality level, and compare it with that reached by competing companies offering the same services, thus maintaining the competition among offerings on a level manageable by users.
Potential users of this research will be:
-private society or agency managing GNSS permanent networks in Italy
-customers of GNSS permanent networks that could employ the quality manual as a benchmark to assess the quality level of the delivered service. <<<

Timescale

24 months

National and international background

The government of the territory is a central element in political activity and management of the public administration and to fulfill its action needs cognitive tools more sophisticated in reference to geography information.
Geomatics in its various subdivisions- Cartography, Positioning, Information Systems, Data Base, Geodesy, navigation is able to make available new and with great efficiency tools for the metric and qualitative knowledge of the territory.
The needs of government land are underlined by specific indications of the European Union.
Actions like INSPIRE tend to standardize on a European level data related to space and their management systems.
In Italy it is very recent the presentation of legislative initiatives focused on the issue of government land and about models to be used for this purpose:
Law Project by Senator Sodano and other initiative informed on February 2007 the 7th, with reference n. 1298. “Principles on landscape planning and implementation and receiving of of Directive 2001/42/EC of the European Parliament and Council dated 27th June 2001 on the assessment of the effects of certain plans and programs”;
Law Project by Senator Ronchi and other initiative informed on July 2007 the 7th, with reference n. 1691. “Standards for the Protection and the government of the territory and the government delegation in the area of urban design taxation and estate and for the reorganization and coordination of existing legislation”.
A profitable implementation of management policies and governance of the Territory must be based on a organic and structured representation of the territory; the legislation in force on land-use planning is based on the concept of environmental sustainability, which becomes the inspirational principle of intervention of change of Territory and discipline of land use. An example in this regard is the Emilia-Romagna Region, where yet mature and multiply the experiences related to the production of landscape planning tools sanctioned in law L.R. 20/2000.
Regions have also recently re-organized on the acquisition front, reuse, interoperability of spatial data-CISIS-and about the definition of production standard and certification of data.
In order to contextualize the research that the proponents intend to tackle is therefore crucial to understand, on the individual issues (summarized for points in the final objectives), the current state of the art and the aspects to develop.

INTEROPERABILITY BETWEEN SYSTEMS OF REFERENCE AND THE TESTING OF RECEIVERS LOW-COST AND NRTK NETWORKS FOR THE LAND REGISTER
When the Italian State was formed (1861), 22 cadastres were present, generally different from each other. Mainly for taxation purposes, due to the deplorable state of the public finance, was thence passed the law n. 3682/1886, aimed to create the unique National Cadastre.
At the initial stage, unavailability of adjusted data didn’t allow to realize a densification networks on large range. In this way 818 local reference systems (“small origins”) were defined upon 19 Provinces. The remaining Provinces were mapped after 1910, with the use of 31 larger reference system (“large origins”). As to cartographic projections, different systems were used in the course of time: Samson-Flamsted the first, followed by Cassini-Soldner and Gauss-Boaga.
When the Royal Geodetic Committee of Italy decided to refer the geodetic network into international ellipsoid (Hayford), oriented at Rome-Monte Mario, the transformations problems of the low order network are risen. It should be noted that the matter of transformation from Cassini-Soldner coordinates to Gauss ones is quite complex, as it needs also to estimate the coordinates of densification points defined before the unification of the networks.
The transformation into WGS84 global system is necessary because the updating of surveying techniques increases efficacy of GNSS positioning, when compared to traditional equipment. A surveyor in the near future will rely upon a real time positioning service, based on permanent stations networks, with a centimetric accuracy. The change in reference system is preliminary so that cartography may prove fully compatible with GPS system, so making of its ample perspectives

TESTING OF LOW-COST SYSTEMS FOR MONITORING OF BUILDINGS AND TRIALS OF NRTK NETWORKS FOR THE MONITORING
During the last few years the hydrogeological instability and catastrophic events are imposing heavy damage to the communities that populate the national territory and the world. Often these disasters could be anticipated with advance and could be managed with rational structural actions.
To do that is essential to provide monitoring and capillary systems working in real time from one side of the territory and on the other of structures that are potentially dangerous.
Great part of the Italian territory is at risk of landslide, and despite that, many buildings, including public ones are present in these areas. The catastrophic events generally are anticipated by precursors phenomena that if are promptly identified can enable the public authorities for both reduce the risk of disaster and for perform any consolidation works directly on the structures.
It is clear that monitoring systems are the basis of the surveillance of the territory. In Italy and in the world are present responsible for real time monitoring of seismic and meteorological events, but there are currently no structures to monitor buildings and structures at risk. Until now, the control of structures was and still now performed using traditional instruments which accelerometers strain-sensor and tiltmeters . These instruments have some intrinsic limits or in the data transfer in real time or in the interpretation of the data. The GNSS permit theoretically to be an adequate alternative for this kind of application.

LAND REGISTER 3-D. PROCEDURES FOR THE DEVELOPMENT AND FILTERING LASER DATA
Growing demand for an efficient land use above and below the ground is motivating cadastre and land management systems to move from traditional 2D systems toward threedimensional ones.
A major concern in realizing the 3D cadastre vision is the development of efficient methods for the attachment of the third dimension to the existing 2D systems. In this regard airborne laser technology that offers direct acquisition of dense and accurate 3D data in the rapid turn-around time offers a very suitable mean to meet this objective.
The transformation of surface data into objects and shapes is, however, not as immediate and requires studying several aspects in more detail.
Whereas developing methods to process LiDAR data is an active research field, little is reported about utilizing this technology for cadastral purposes.
We can identify three major aspects that should be studied in some detail. The first one is fundamental and concerns elements of accuracy, co-registration of the two datasets and required point density. The second one concerns recognizing objects and their shapes in relation to cadastre purposes, and the third one concerns the integration of the data with the existing databases.
Laser datasets are merely a set of points that sample the scanned surface.
Many studies have been conducted and are still in course on the segmentation criterions of the laser data that classify in automatic mode the data relative to the echoes coming from the ground, from the vegetation and from the buildings.
It must be observed, however, that the data from ALS LIDAR is basically derived from a 2.5D survey that can't provide detailed information on the volume of the object detected for the presence of missing parts hidden from hangings, balconies, porches and tunnels unidentifiable from the top.
It is therefore necessary to integrate ALS data (or the aereal images) with other sources.
The recent development of a new system of aereal photogrammetry where cameras tilted of about 45 degrees from the nadiral direction, able to provide a lateral view (Pictometry) is a first step towards the possibility of obtaining a complete vision and modeling of 3D objects.
The survey of the object by using terrestrial Laser scanning is another way to obtain data about those parts of the buildings not covered by aerial photogrammetry or the by airborne laser. The great precision and the high level of detail obtainable by Laser Scanner make it one of the most studied and used instrument in the field of survey.
On the other hand, a technique called MMS (Mobile Mapping Systems) is going increasing toward a complete integration of different techniques and methodologies (GPS, INS, Laser, Photogrammetry) to get quickly from a mobile van informations on elements of the territory to be represented. The sense that can be given to the word "representation" can obviously be very broad ranging from the construction of topographic database, the establishment of digital mapping and GIS, to the construction and visualization of 3D City Models.

CERTIFICATION OF NETWORK RTK
The building, also in Italy, of GPS permanent station networks providing real-time services for topographic surveys expanded the uses of GPS instrumentation, but raised new issues regarding legal aspects and products certifications.
The GPS permanent station networks consist of points where GPS are permanently placed, constantly recording the observations and transmitting them in real time to a control centre. Using specific software, the received data are used to calculate network differential corrections, distributed for example as virtual reference stations placed in the surroundings of the survey location and non linked to any actual reference point.
In various European nations, such as the United Kingdom, Switzerland, Austria, Germany and Spain, just like in the United States and Australia, the real-time permanent station networks have been built by (or under the supervision of) the national mapping agencies, thus solving endorsement issues. Despite that, these agencies did not avoid a quality management of their products, and operated under the quality system defined by the ISO 9001 standard. On an international level, there is no specific certification for providing permanent station network services. For example, the Ordnance Survey is ISO 9001 certified for distributing geographic information and providing services, including impliedly positioning services; the Australian AUSLIG is ISO 9001 certified for distributing geographical products including GPS and SLR permanent station networks, but not real-time.
In Italy, the transfer of most competences on this matter to local agencies moved the regional governments or other subjects, such as GPS instrumentation distributors, to built their own private permanent station networks on a regional or national basis. These networks compete to the propagation of the national reference system, joining the IGM95 network realized by the national mapping agency (IGM) as a materialization of the ETRS89 reference frame adopted on the European level. These private networks obviously lack any endorsement, reserved to the formerly cited national network; nonetheless, they are currently used by all operators, both public and private. Some of the private companies also have ISO 9001 certification, but not for managing GPS permanent networks. Thus, there is no specific model to refer to when applying for a ISO 9001 certification for providing real-time positioning services. In the course of the last few years many research projects concerning the quality of data have been financed (PRIN 2004 Prof. Sansò and PRIN 2005 Prof. Barbarella). These projects produced a set of documents providing guidelines for building and managing permanent station networks. Until now, anyway, there has been no real attempt to give these studies a structure compatible with the ISO 9001 standard.

STUDY OF GEOGRAPHIC INFORMATION SYSTEM FOR THE INTEGRATION OF TERRESTRIAL, GEOGRAPHICAL AND REMOTE SENSING INFORMATIONS
International projects, especially by NASA, are currently being developed employing sensor networks and sensor webs, using the network to communicate between sensors placed on different platforms and to transmit data between them. A sensor network can provide data at different levels of spatial definition and temporal frequency, particularly when states of alert occur (from satellite global and regular monitoring up to ad hoc flights and data collection over monitoring networks on the ground).
An example of this approach is the recent COSMO-SkyMed space program conceived for satisfying requests of "up-to-date and quickly available information in order to take decisions faster, more adequately meeting the growing demands of civil protection in the management of natural and induced hazards, environmental resources and security”.
In the same direction operates also the GMES project - Global Monitoring for Environment and Security, "a joint ESA / European Commission project based on data collected by satellites for Earth observations and a network of stations in situ" (www.esa.it) intended to support European policies on environment and security. At a European level, work has recently been carried out to implement the INSPIRE directive, whose objective is to establish an infrastructure for spatial information in the European community.
The concepts underlying all such initiatives, which should define the rules for the access and use of geographic information, are that of interoperability between heterogeneous data and services as well as that of integration (semantic, spatial, temporal) of data and/or technologies which play a key role in the dissemination of information.
A system for integrating, elaborating and consulting the data products can now be effectively implemented thanks to the results achieved in various fields:
1) technological innovation in wired and wireless telecommunication, Internet and what is called digital infrastructure (Zimmerman and Horan, 2004)
2) the development of communication architectures for the interconnection and the remote monitoring of distributed instruments (Prin2004 CRIMSON).
3) data fusion techniques merging multi-source and multi-scale data and allowing the integration of global coverage with surveillance point data, providing real-time information on potential risk phenomena (volcanoes, landslides, etc.).
4) advances in the use of interoperability-oriented architectures (SOA Service-Oriented Architecture) and in Open Source environments (it is e.g. now possible to take advantage of guidelines on services of interest provided by the Open Geospatial Consortium).

MONITORING OF DISASTERS BY REMOTE SENSING TECHNIQUES
In the last few years the images coming from the new high resolution satellites are frequently used to provide useful information in the process of evaluation and analysis of disasters.
The first satellite constellation, called Disaster Monitoring Constellation (DMC), designed with the sole task of "control of the territory" in occasion of disasters, consists of four satellites placed in orbit between 2002 and 2003. Several other satellites useful for risk management and prevention have now added to that constellation. Besides the well-known QuickBird, IKONOS, Spot 5 and LANDSAT, there are a number of new missions as Cartosat2,Formosat,Kompsat2,the European program called Cosmo Sky-Med.
The above said mission add to the DMC and to the others used in the project called International Charter "space and Major Disasters". The International Charter aims at providing a unified system of space data acquisition and delivery to those affected by natural or man-made disasters through Authorized Users. An Authorized User can request the mobilization of the space and associated ground resources (RADARSAT, ERS, ENVISAT, SPOT, IRS, SAC-C, NOAA satellites, LANDSAT, ALOS, DMC satellites and others) of the member agencies to obtain data and information on a disaster occurrence. <<<