Major Geodetic Excursion 2024 to Northern Germany 7.10 - 11.10.2024

This excursion provided valuable insights into the geodetic and geospatial technology landscape, connecting theoretical learning with real-world applications across engineering, maritime monitoring, space exploration, and environmental sustainability.

Monday, 07.10.2024
Dr. Hesse und Partner Ingenieure (DHPI)

• Focus: Geospatial data and advanced surveying services.
• Technology: Strain gauges, fiber optic sensors, and hydrographic surveying.
• Highlights: Cutting-edge surveying solutions, like 3D laser scanning and underwater mapping with Hydromapper, providing data in real-time using MATLAB for visualization.
• Opportunities: Student jobs, internships, and graduate positions were discussed.

Tuesday, 08.10.2024
Levensauer Elevated Bridge Construction Site of the Wasserstraßen Neubauamt (WNA)

• Project Overview: Replacement of the aging bridge over the Nord-Ostsee-Kanal (NOK).
• Challenges: Limited canal closure times, careful planning for traffic disruption, and slope monitoring with automated survey prisms.
• Environmental Impact: Protection of the bat population by integrating the existing abutment into the new bridge structure.

Wednesday, 09.10.2024

1. Federal Maritime and Hydrographic Agency (BSH)
   • Role: Marine environmental monitoring, shipwreck detection, and oceanographic research.
   • Capabilities: Water level forecasting, storm predictions, and simulation technology for testing navigation systems.
   • Key Focus: Sustainability and public access to maritime data through the Maritime Datenzentrum (MDZ).
2. German Electron Synchrotron (DESY)
   • Research Focus: Particle physics, specifically in the search for Axions and dark matter.
   • Technology: A 6 km underground particle accelerator; precision alignment for geodetic applications, using photogrammetry and precise surveying.
   • Applications: Beyond fundamental science, technologies could aid industries like telecommunications and semiconductor manufacturing.

Thursday, 10.10.2024
OHB Space Technology Company

• Scope: Satellite development and space systems, including Galileo and CO2M satellites for navigation and environmental monitoring.
• Satellite Production: Efficient assembly, testing, and satellite launch preparation.
• Opportunities: Career prospects in internships, thesis projects, and working-student positions.
• Highlight: Integration halls with clean rooms where satellite assembly occurs, showcasing the company’s role in advancing space exploration and satellite monitoring.

Friday, 11.10.2024
ZARM (Center of Applied Space Technology and Microgravity)

• Facility: Bremen Drop Tower, a 146-meter structure for microgravity experiments, achieving up to 9.3 seconds of weightlessness.
• Research Relevance: Microgravity experiments aid in space mission preparation and simulate space-like conditions on Earth.
• Applications in Geodesy: Practical applications include satellite orbit calculations and microgravity studies crucial for geodesy.

Our unforgettable journey commenced in Hannover, and our trusty black bus carried us swiftly to Bern, the enchanting capital of Switzerland. Over the course of our exploration, we spent three nights in Bern, immersing ourselves in the city’s vibrant atmosphere, and one night in St. Gallen, experiencing the local hospitality.

Our first day of discovery, on October 3rd, led us to the picturesque city of Lausanne. Here, we delved into the cutting-edge world of technology, visiting ”Pix4D,” a leading Photogrammetry software company, and the esteemed ”EPFL,” the Young Technical University of Applied Sciences. The insights gained from these visits were invaluable, offering us a glimpse into the future of technology.

Continuing our journey, on the morning of October 4th, we found ourselves at the renowned University of Applied Sciences and Arts, Institute for Geomatics, located in Muttenz near to Basel. The institute’s dedication to innovation and education left a lasting impression on us. In the afternoon, our curiosity took us deep underground to Mont Terri, where we explored the Underground Rock Laboratory. This facility is dedicated to groundbreaking research on hydrogeological, geochemical, and geotechnical aspects of clay formation concerning radioactive waste disposal — an endeavor of critical importance.

The following day, as we returned to Bern, we made a fascinating stop at Zimmerwald. Here, we marveled at the Satellite Earth Observation Station, where cutting-edge technology is harnessed to monitor our planet from above. The insights gained from this visit underscored the vital role of satellite technology in our modern world.

Our final stop was in Heerbrugg, where we had the privilege of visiting Leica, a worldrenowned manufacturer of cameras, optical lenses, and various scopes. This visit provided us with a glimpse into the craftsmanship and precision that define Leica’s products, reinforcing our appreciation for Swiss engineering excellence.

In summary, our excursion through Switzerland’s technological landscape was both enlightening and inspiring. We witnessed firsthand the innovation and dedication of leading companies and educational institutions, leaving us with a profound sense of admiration for the advancements shaping our future. This journey not only expanded our knowledge but also deepened our appreciation for the remarkable contributions Switzerland makes to the global technological arena.

Fehmarn-Belt-Tunnel

The Fehmarn Belt Tunnel is an engineering project with the aim of connecting the German island of Fehmarn and the Danish island of Lolland with a tunnel. The tunnel will be realised as an immersed tunnel. It will consist of 79 individual elements that will be positioned in a channel on the seabed. A differential GNSS system will be used for positioning, which has been specially set up for the construction of the tunnel. Construction will take place simultaneously from both sides, so a high degree of precision is required to avoid subsequent corrections.

Leica Niederlassung Odense

On the second day of the geodetic excursion, we visited Leica Geosystems Company. Leica Geosystems is part of the Hexagon Group and works worldwide on solutions and instruments in various areas of geodesy and geoinformation. Some of these were presented to us during the visit. These included research and development in the field of machine control systems.

Danish Geodata Agency

On the third day of the excursion, we visited Aalborg, Denmark's fourth largest city in terms of population. The Danish Geodata Agency was founded there on 1 January 2016 and was the destination of our visit. It is responsible not only for land registration, but also for the sale, production and development of nautical charts, nautical publications and other maritime products.

Onsala Space Observatory

On Thursday morning we travelled from Gothenburg to Onsala to the Space Observatory. After a short lecture, we were given a guided tour of various radio antennas on the grounds of the Space Observatory. The Space Observatory, as part of the Chalmers University of Gothenburg, is the national centre for radio astronomy and provides the equipment for scientists to study the Earth and the universe.

Olidan Hydro Power Station Trollhättan

The Olidan Hydro Power Station is located on Göta Älv, Sweden's longest river, which bridges a total height difference of 44 metres from Lake Vänern to its mouth in Gothenburg - 32 metres of which are in Trollhättan alone.

Smaragdmine von Byrud

There is only one mine in Scandinavia where emeralds have been mined. It is located around 60 kilometres from Oslo and belongs to Byrud Farm on the shores of Lake Mjösa in Minnesund. The farm is almost 1,200 years old, making it one of the oldest farms in the region. We took a walk along the shore of Lake Mjøsa. At the mine, we learned more about the geological aspects of the area.

The first two days of excursion on 09-10 October took place in Rostock where different places were visited such as the “Fraunhofer Einrichtung für Großstrukturen in der Produktionstechnik (IGP)”, “Bundesamt für Seeschiff-fahrt und Hydrograhie (BSH)”,and the “Universität Rostock”. On 11.10 the Deutsches Zentrum für Luft-und Raumfahrt (DLR) in Neustrelitz was visited and later in the afternoon, the journey took place in Berlin were at first the “Infobox Humboldforum” in Berlin was visited. On 12.10 there was a trip to GFZ in Postdam and in the afternoon the DLR base in Berlin was visited. At the last day on 13.10 the excursion ended with a presentation by Geobusters in TU Berlin and finally the Grundstücksentwicklung GmbH (DSK) were visited in Berlin.

We visited the Fraunhofer-Einrichtung für Großstrukturen in der Produkt-ionstechnik (IGP) located in the University of Rostock premise where we had firsthand information on the measurement accuracy required in the fab-rication of large structures especially along the curves, edges and contours of such structures. We were opportuned to see a robotic laser scanner being used in measuring a rotor blade before appropriate simulation cuts were made at the appropriate points along the intended lines. We also had the opportunity of visiting the 3D Laboratory where we saw a simulation of an industrial plant layout being displayed on screen and we could see the different areas in the plant using Wii technology and Virtual Reality to monitor the production lines of the industrial plant. We also saw a visual instruction manual used in the support of industrial machines and replacement of service parts when required so that the technician would not have to go about with handbooks for that machinery.

As first part of the programm on tuesday we visited the "Bundesamt für See-schifffahrt und Hydrographie" (BSH) in Rostock. We startedwith a guided tour through their vessel named "Deneb", which is used for surveying the seabed, research and the search for shipwrecks mainly in the German territorial and coastal waters of the Baltic Sea and the North Sea. We could see the equipment forthe divers who have to do a dangerous job to search the wrecks in the opaque water. On the ship's bridge we could sit on the captains chair and we could learn something about the navigation equip-ment and the charts they use on the Deneb to navigate.The collected data is used for several products, which are provided by the BSH, for instance nautical charts and the so called "Nachrichten fürSee-fahrer" (NfS). The internal printing office was our next stop, where we could find out more detailed informationabout the production process of the charts. The visit to the BSH endend up with a presentation about the or-ganization of the institution and the handling of the nautical data. Finally, the ship's horn of the "Deneb" sounded and we watched the departure of the vessel which went out for surveying for the next ten days.

The Geodesy and Geoinformatic department of Rostock University is under supervision of Professor Ralf Bill and currently 16 colleagues are having researches and projects there. On 10thof October 2017, Professor Ralf Bill and three of his colleagues gave an introduction about the institute along with the current fundamental researches being done there. According to Professor Bill’s speech, as the Geodesy and Geoinformatic department is combined with agricultural and environmental engineering faculty, therefore the researches are mainly focused on urban and regional planning along with coastal and agricultural topics. Afterwards three separate topics were presented by the colleagues. The first topic was about land escape change and its structure which is based on land classification and land observation using photogrammetric methods along a specific time line. The main purpose of this research is to be able to track the changes of land usage and essential phenomena that might have happened during a specific time period. The second subject was to use photogrammetric techniques in order to recognize specific plans that grow in agricultural lands that might be harmful mainly for animals and consequently the nature by using aerial photographs that are taken repeatedly over the target land in a specific time period. The main purpose of this research is to be able to detect certain areas in which there is a high probability for a specific poisonous plant to grow and notifying the farmers to remove them as quick as possible.At the end they provided more information about the opportunities for distant leaning by using the online platform they provide which is called Open-GeoEdu (opengeoedu.de). It is based on various existing open source platforms. It is obvious that the main purpose for this work is to enable students, professors, researchers, and etc. to have the possibility to gain information by using internet and trustful online sources which is the main concern in nowadays world full of different data.

In the first part of the presentation the basic information about DLRwas explained. DLR is not acting only as space agency but also as research institute and project manage agency. They have approximately 8000 em-ployees across 33 institutes and facilities at 20 sites. Including the offices that they have in Brussels, Paris, Tokyo, and Washington, they are proven to have international influence at their area of expertise. Their research areas are comprised of Aeronautics, Space Research and Technology, Transport, Energy, Defense and Security, Space Administration and also Project Manager Agency. One of the main focus in their satellite mission, with the satellites Advanced Composition Explorer (ACE) which has been operating since 1997 and Deep Space Climate Observatory (DSCOVR) which has been giving data since 28thof July2015, is solar research satellites. They position the satellite Lagrangian point between sun and earth facing the sun wind. On the other part, the Institute of Communication and Navigation Nautical Systems, which is another department within DLR, have three main focuses on their research. The first one is Multi-sensor systems, which currently working on a robust and reliable Position Navi-gation and Timing (PNT) data provision, increasing the safety of the vessels (collision avoidance). The second focus is Maritime Services, which handling in Multi-GNSS integrity monitoring by augmentation systems. Lastly, on part of Traffic Surveillance, they are researching about Automatic Identification System (AIS) monitoring target detection and tracking (Radar).The second presentation at DLR in Neustrelitz was about the use of Global Navigation Satellite System (GNSS) as a part of a Multi Sensor System (MSS) on a vessel. Anja Heßelbarth talked about the accuracy conditions during the navigation of a ship. The shipping has different challenges for driving on oceans, at coastlines, on canals/rivers or in a port. For the waterways inside the country the bridge fits are very important. Many different GNSS methods can be used for this application: the code based differential GNSS (CDGNSS) and Single Point Positioning (SPP) or the Precise Point Positioning (PPP) and the Real Time Kinematic (RTK) as the phase based methods. The speaker illustrated, that the balance between the costs and the effort is important. She presented the project LAESSI, which is planned for the period 2015-2018. In this research project are many companies involved, like the in-innovative navigation GmbH and the DLR. It is supported by the “Bundesministerium für Wirtschaft und Energie”. The goal of this project is to create a driver assistance system for the inland waters, so that the risk of collisions will be minimized. The main focus is on the bridge drive warnings, docking assistants, route leading assistants and conning displays (track of the ship). The third presentation in DLR was mainly about ionospheric modeling activities. Ionosphere is a layer in the atmosphere which exists 50-60 km above GPS height and has influence in positioning, since it turns the satellite signal into curvature rather than a straight line. Therefore, the goal of their research was to model ionosphere (in 3-d) and to be able to develop an ionospheric correction algorithm which performs better and is easier to han-dle as an alternative to existing algorithms such as GPS ICA which is very simple but corrects only for 50% and Galileo NeQuick which is very time-consuming. This model was named NTCM or Neustrelitz TEC Model. Later versions of this model are NTCM-BC with F10.7 (solar radiation index) and NTCM-Klobpar withklobuchar model parameters and no need of F10.7. Another subject explained in this presentation was the monitoring of the 2015 eclipse over Europe. Because of the fact that there was a o-called switching off of the Sun at that time the ionization decreased and this was monitored and compared with 26 other TEC models (13 days before and 13 days after the eclipse) After lunch we had a quick tour of the DLR. We visited the headquarter that receives satellite signals by the giant receivers in the yard and also we were presented about nautical navigation in which one of the hard parts is to know the positions of other vessels due to the bad visibility andso now many vessels are equipped with AIS systems as well as radar. IMPC was also introduced which stands for Ionospheric Monitoring and Prediction Center. There they talked more about the impact of ionospheric effects as a challenge for navigation, communication and earth observation and how IMPC provides a service for science, governmental decisions, commercial applications and public interest.

After arriving in Berlin the first station was the Humboldt Forum next to the island of museums. Mr Schnurbus, an art historian, expected us to tell us about the project from the Förderverein of the Berliner Schloss. The plan is to rebuild the facade and the general building of the palace -it has been destroyed in 1950 -as it was before. After the opening in 2019, it will contain an ethnological collection which will make it a world museum. We also don-ated a small amount for the completion of the project.

At Thursday morning we visited the GeoForschungsZentrumin Potsdam. At first, a guided tour by Josef Zens was planned on the Tafelberg. Different buildings of the science park were introduced to us. For example, we visited the Helmert-Turm, Großer Reflektor, Einsteinturm, Paläomagnetisches Laborand Klimareferenzstation. In former times, the Einsteinturmwas used as a solar observatory todo spectral analysis. Now, the main purpose is to calibrate instruments and teach students. The Paläomagnetisches Labor is a magnetic observatory used to observe magnetic fields of the earth. Because of that, the building is made of non-magnetic materials. Due to disturbances from railway constructions near the campus, the measurements were strongly influenced. The Klimareferenzstationhas the longest uninterrupted measurement of climate parameters since 1893. It measures three times a day the air temperature, humidity, precipitation as well as other meteorological parameters. The Deutscher Wetterdienstuses these data nowadays.

After the tour, we attended five presentations about Remote Sensing and Space Geodetic Techniques. The first one was “Imaging of the Earth at night” by Dr. Kyba. With his results you can detect the human activity and change over the years during the night time. Different difficulties were mentioned in his presentation. For example, the differences between artificial and non-artificial lights and the angular emission direction are problematic. The next presentation was “Automated landslide detection using optical multi-sensor time series data” by Dr. Roessner. The detection of landslides is based on the decrease of vegetationwhich can be observed with the NDVI. Dr. Förster introduced us to the topic “EnMAP Imaging Spectroscopy Mission”. The content consisted of the principles of imaging spectroscopy, the application fields and the current situation in space-borne 5imaging spectroscopy. “HyLIDAR –synergistically hyperspectral and lidar data fusion” was presented by Brell. In the end, Dr. Dick gave a talk about “GNSS and Atmosphere Sounding”. The aim was to calculate the integrated water vapor that are used in weather forecast, atmosphere modelling and climate research.

On the morning of Thursday (12/10/17), the participants of the excursion visited the German Aerospace Center (DLR) in Berlin. At the aerospace centre, the program consisted of an introduction and five presentations. The introduction, given by Ms. Kirtstin Ebert gave a general idea about DLR Berlin, the number of employees there, the different kinds of research works pursued there, and general information about DLR in other locations of Germany.The first presentation dealt with the Jupiter Icy Moons Explorer (JUICE) mission, and was given by Mr. Alexander Stark. He gave information about previous missions of the world to Jupiter, and the missions planned in future –JUICE and Europa Clipper (by NASA), and how JUICE was different, since it dealt with the moons –Europa, Ganymede, and Callisto. He also described all the prior information we have of these moons, how we got the information, and what we planned to achieve with new information. The mission, which would launch in 2022, and would reach in2030, would trace the orbit from Earth-Venus-Earth-Mars-Jupiter. With the mission, the a 10 cm image range resolution is hoped to achieve to be able to study the moons better. The second presentation, given by Mr. Giese, was about the comet 67P, which was traced by ROSETA (launched by ESA in 2004) and reached the target comet 67P at 3.5AU in July 2004. The scale of the camera was 2m/pixel, and the wide angel was 10m/pixel. For the image processing and 3D reconstruction, about 30 million tie points were matched. As described in the presentation, the motivation was to study the origin of water on earth, and to gain more information about the origin of universe and lifein general. A 3D model of the comet which was developed by DLR was also shown.The third presentation, given by Mr. Gwinner, was about the Mars Missions, for which we have the data from 1970s till now, and about some missions which were purely by the European Space Agency.The fourth presentation, given by Mr. Preusker, was about the Cassini Mis-sion which had to motivation to study Saturn, including its rings and natural satellites, and lasted from 1997 to 2017. Particularly interesting was the study from Phoebe, as it revolves in the opposite directions of the direction of the rotation of Saturn. The fifth talk was about 3D visualization. It was presented by Mr. Eigner. It showed how the 3D space outside of earth can be presented on a computer, andwhat the applications of these 3D constructions are.

On 13th in the morning, we visited Mr. Genz from “Geobusters” at Technische Universität Berlin. Mr. Genz is an expert of virtual reality ( VR ). He gave us a fantastic presentation about virtual reality.This presentation consist of 3 parts. In the first part Mr. Genz introduced us some current achieved technologies for information obtaining and visualization about VR, MR and AR. Then he took some examples for telling us the differences between them. From this part of presentation we gained some basic concepts of VR and came to know that VR is widely used not only inmeasurements, but alsoin other fields e.g. architecture, education and medicine. The second part of the presentationwas about the process of producing a VR product. In order to generate a VR product, we need a 360°camera. In this part, a multi-sensor system was introduced. This multi-sensor system consists of one 360°camera to capture scenes and one tachymeter to monitoring the position of the camera. With an ATV carrying this system, people can drive from one place to other place to do the measurements easily with a relative lower cost.The multi-sensor system surveying process consists of three steps. First, for reducing the working time and human resource, we need do the pre-calculation before surveying. Then the required equipment are not only the specific camera for point cloud dataset and tachymeter for leveling surveying, butalsoGNSS antenna for 3D coordinates.Finally, all the data which obtained by this multi-sensors will be calibrated and processed by specific software. More the details are shown below pictures. In the last part, Mr. Genz demonstrated many different kinds of VR instruments. There was a VR glasses that can monitoring a exploration of a room. An VR driving system that monitoring driving an ATV was also introduced. This kind of instruments can be widely used for education and demonstration of some special pro-cedure.

Die Förderergesellschaft Geodäsie und Geoinformatik unterstützte finan-ziell die Exkursion. Dafür bedanken sich die teilnehmenden Studierenden der Fachrichtung herzlich. Die Reise wurde dieses Jahr federführend von Christine Bödeker vom GIH geplant. Weiterhin involviert waren Jonas Bostelmann vom IPI, Malte Schulze vom IKG, Mohammad Omidalizarandi und Xin Zhao, beide vom GIH, sowie Christoph Wallat vomIfE.

This year's major geodetic excursion to Spain took place from 25 September to 1 October 2016. The following report, written by students, explains the various items on the programme.

On Monday morning, we drove to our first stop on the programme, the company GeoNumerics, which is based on a science campus in Castelldefels near Barcelona, significantly on Avinguda Carl Friedrich Gauss. GeoNumerics specialises in the mathematical modelling and calibration of multi-sensor systems. In a variety of presentations, we were first introduced to the company, followed by a presentation of the core products and, at lunchtime, current projects. For example, an emergency system was shown in which a two-bit emergency signal is sent to rescue teams from a wristband via Galileo with the most important information. One highlight was the innovative mapKITE system, a combined method for aerial mapping using a multicopter and terrestrial support vehicle. A coded target is attached to the roof of the vehicle, which serves as a ‘kinematic’ control point (see photo). This allows the number of control points required along a route to be reduced. During a coffee break after the presentations, there was room for further questions and discussions. The event concluded with a visit to the canteen on campus together with GeoNumerics employees.

On Monday afternoon, we visited the Basílica i Temple Expiatori de la Sagrada Familia, which is the full Catalan name for the basilica. The visit was accompanied by an audio guide, which provided interesting information about the building. Sagrada Familia is a famous Roman Catholic church, which was largely designed by Antonio Gaudí. The church is a UNESCO World Heritage Site and was consecrated a basilica minor by the Pope in 2010. It has been under construction since 1882 and is currently scheduled for completion in 2026 to mark the 100th anniversary of Gaudí's death. When completed, Sagrada Familia will have 18 towers with colourful spires. Two façades can currently be viewed: the Nativity façade and the Passion façade. While the Nativity façade was largely completed during Gaudí's lifetime, construction of the Passion façade is not yet complete. The Passion façade has some elements that are reminiscent of Gaudí. For example, the tops of the soldiers' helmets resemble the roof of a building designed by Gaudí. In the interior, the stone columns, which are intended to resemble trees, and the coloured windows are particularly impressive. The altar, above which hovers a figure of Jesus on the cross, was unfortunately not visible due to construction work. The visit to the Sagrada Familia was very interesting and definitely worthwhile.

On Tuesday morning, we left our hostel very early to go to the airport again, where we had arrived two days earlier. After the usual airport security checks, we were met at a side entrance by airport staff and driven to the hangar of the ICGC (Institute of Cartography and Geology of Catalonia). During our visit to the hangar, we were given an explanation of some current projects and a demonstration of the technologies used, i.e. the sensors that are used to collect data. Most of the projects flown by the ICGC are commissioned by the public sector (around 80%), with the remaining projects coming from the private sector. The ICGC has three of its own aircraft to complete these projects, one of which was in the hangar during our visit. One of the current projects being flown for the state of Catalonia is to cover the entire area of Catalonia, which is around 28,000 km². The flights are carried out with various aircraft at an altitude of around 2,500 metres. The corresponding flight planning maps were also shown and explained to us. Various sensors were set up in the hangar. Some of these were familiar from photogrammetry lectures, but it was exciting to see them in real life. This included a Leica DMC I, a Leica RCD30 and an AISA Eagle hyper-spectral sensor. A Leica ALS50-II laser scanner was also installed in the aircraft in the hangar. The latest acquisition, a Leica RCD30, is a camera that is used for oblique images, e.g. for 3D mapping in urban areas. It consists of one vertical camera and four cameras tilted by approx. 40 degrees, which can be clearly seen in the photo (right). In addition, we were shown the control system for flight management, which also includes a screen for monitoring the recording process. For example, it is possible to mark unusable images (e.g. due to clouds) directly during the flight in order to save time during post-processing. The AISA Eagle is a hyperspectral sensor that is used at the ICGC in forest management, environmental monitoring (e.g. of water areas), land use planning and precision farming. The system consists of the hyperspectral sensor with data acquisition module, a GPS/IMU unit and the CaliGeoPRO software for pre-processing the data. The current projects in which the sensor is used are mainly concerned with river pollution and agricultural applications.

After an exciting morning at the airport, we visited the Catalonian Institute of Cartography and Geology (Institut Cartographic i Geologic de Calalunya, ICGC for short) in the afternoon. This institute has only existed since February 2014 following the merger of the geological institute and the cartographic institute, and the merger of the two areas has given the ICGC a wide range of tasks, which were presented to us in a lecture. One important task is aerial photography with the sensors and aeroplanes already presented in the morning. The creation and provision of various thematic maps also plays a major role. In this context, the individual products of the ICGC were discussed in more detail, e.g. topological, historical and geological maps, 3D models and various services. The ICGC is very interested in the implementation of the INSPIRE directive and therefore provides a lot of geodata related to Catalonia on its homepage in an interoperable way. A new app was also presented that provides real-time information on seismic activity in Catalonia and around the world and displays interesting facts, such as the distance to the epicentre, etc., on an interactive map. There is also an Instamaps application, for example, where users can access data from the ICGC and create their own customised maps. In the further course of the afternoon, specific current research projects of the institute were discussed in more detail, e.g. a study on land subsidence in Catalonia. Another major project is currently developing a prototype warning system for forecasting coastal storms. The aim is to reduce the number of victims of natural disasters such as flooding. As the ICGC is also active at an international level, we were given a brief insight into some cross-border co-operation projects. In a subsequent guided tour, we were given the opportunity to get to know the institute better and to take a closer look at some topics using scientific posters. All in all, it was a very interesting and informative afternoon, during which we were given a comprehensive insight into the activities of the ICGC.

The day after the bus journey from Barcelona to Madrid, we travelled to the Parque Technologico de Madrid technology park in Tres Cantos to visit the company gmv innovating solutions. On arrival, we were taken straight to a presentation room where, after a brief welcome, we were introduced to the history of the company. GMV innovating solutions was founded in Madrid in 1984 and has locations in ten countries with a total of more than 1,100 employees. The company is active in the fields of satellite navigation, mission analysis and space and security technology, among others. Later, it also added activities in the telecommunications and transport sectors. They specialise in safety-critical GNSS applications. Following this introduction to the company's history, we were shown the basics of geodetic measurements using GNSS. Among other things, important things such as clock errors and knowledge of the satellite position were discussed. The Precise Point Positioning measurement method in particular was then presented. The ODTS module (Orbit Determination and Time Synchronisation) was also presented. This is used to calculate precise orbits and clocks within the PPP post-processing service ‘magicGNSS’ developed by gmv. NAfter this presentation, the excursion group was divided into two subgroups. One subgroup remained in the presentation room, while the other was taken to the forecourt of the company. Here we were shown a GPS antenna and a GPS receiver, which are used for real-time PPP applications with the aid of a tablet. We were then shown the possibilities of this application by using the antenna to trace the company logo on the ground in front of the building, while we were able to follow the trajectory plotted on an orthophoto on the tablet in real time. The app also had the usual GNSS visualisations, such as a skyplot of the visible satellites. After this demonstration, we were briefly taken to the roof of the company, where we were shown another antenna. At the end of this outdoor tour, the two subgroups swapped places. This was followed in the presentation room by a demonstration of the PPP post-processing service ‘magicGNSS’ developed by gmv. We were shown in detail what options the service offers and how to use it. At the end, we had the opportunity to get to know some gmv employees and chat over a tapas buffet. The following afternoon was free due to a last-minute cancellation. The students used the time to visit Madrid, including an urban development project.

On Friday morning, the Institut Geográfico Nacional (IGN) was scheduled as the last point of the excursion. After a welcome in the foyer, we were invited into the seminar room, where several employees introduced the authority with the help of presentations. After a brief insight into the structure and organisation of the authority, the various products that are produced and processed at the institute were presented to us in more detail. In addition to a large selection of national and international map material at different scales, various other geodata is also made available there. These are generated on the one hand from regular aerial photography campaigns, which are carried out nationwide, and on the other hand from terrestrial measurements. In addition to freely available geodata, special data for disaster control, police and fire services is also produced and made available. After this insight and a short discussion, we had the opportunity to have lunch in the canteen. We were then invited to the authority's own map museum. In addition to historical maps and globes, there were also expert explanations that provided an interesting insight into the history of surveying. Particularly interesting was the digital, interactive map material, where a direct comparison could be made between an early modern map of Madrid and a modern satellite image of the Spanish capital. This impressive and very informative conclusion brought the programme to a close and the group left with some great impressions.

The last stop on the great geodesic excursion was the Royal Palace of Madrid, Palacio Real de Madrid. This impressive monument is the official residence of the Spanish royal family and is still used today to host state ceremonies, such as receptions for heads of state. However, the current ruler, King Felipe VI, normally resides in the somewhat more modest Palacio de Zarzuela. The wide, open courtyard of the palace invited us to marvel at the royal riches during a tour. The interior of the palace is richly decorated with all kinds of precious individual pieces such as sculptures and handicrafts. Even the statue of King Charles III on the entrance staircase looked very impressive under the antique ceiling paintings. Some of us opted for an audio tour through the rooms to gain even deeper insights into the history of the palace. Among other things, the tour took us through the banqueting hall with its long rows of richly decorated chairs and expensive cutlery. The crown and the queen's throne are also sure to remain in every visitor's memory. The outside area of the palace presented itself to us with a far-reaching view over the green hill of Madrid in the background, the Casa de Campo. The Royal Armoury Museum was also well worth a visit. It contains a rich collection of old weapons and armour from different eras. As a souvenir of a fantastic excursion through Spain, we took a group photo in the large courtyard of the palace.