- Topic
- Mobility management
- Urban mobility planning
- Country
- Germany
- Resource type
- Case study
The City of Aachen is pioneering ‘digital twin’ technology to enhance urban management and sustainability. By developing a comprehensive data platform and a digital twin focused on transport infrastructure, Aachen is setting a new standard for smart cities. The 3D model supports improved decision-making, coordination across city departments, and greater public engagement. Aachen’s efforts align with broader European Union goals, demonstrating the potential of digital twins to advance urban sustainability and innovation.
Context
Urban data is an invaluable resource, providing critical insights into the processes that shape city life. With vast amounts of information generated by sensors, Internet of Things (IoT) devices, and other sources, cities are increasingly looking for ways to leverage this data to improve decision-making. Digital twins provide a powerful platform for cities to collect, integrate, and visualise this information, creating dynamic, living models that can support the real-time management of urban systems [1].
These virtual models enable cities to not only monitor their infrastructure but also to track the dynamics of urban mobility, such as user behaviour and demand. By simulating different scenarios, digital twins offer an opportunity to test the impact of specific interventions before they are implemented, leading to more informed and effective planning decisions. In the field of mobility, for example, digital twins can help optimise traffic flow, reduce congestion, and enhance public transport systems, all while responding to real-time data [3].
Digital twins are particularly valuable for their ability to support inter-departmental collaboration within city administrations. By providing a shared view of urban systems, they facilitate better coordination between departments, improving efficiency and reducing the likelihood of miscommunication. Moreover, by making urban data and planning processes more transparent, digital twins can foster public engagement, allowing citizens to better understand and participate in the development of their city.
However, to fully realise these benefits, cities must first invest in thorough preparation. This involves ensuring that all relevant data, models, and systems are compatible and can be seamlessly integrated into the digital twin. Additionally, ongoing monitoring tools and practices are essential to ensure that the digital twin remains accurate, continuously reflecting real-world conditions [4].
Digital twins in the EU:
With the growing relevance and interest in digital twins over recent years, the European Commission has recognised their role as ’powerful tools for planners and authorities’ [5]. Their potential to promote sustainability across sectors has led to digital twins being eligible for funding through the European Green Deal, which aims to reduce net greenhouse gas emissions to zero by 2050, in part by promoting innovative technologies [6]. As highlighted in the COM(2023)751 Communication from the Commission [17], one of the value-added use cases of the common European mobility data space (EMDS) is to help building an ever-richer digital twin of the driving environment. In several EU projects, such as ACUMEN [19], OMICRON [20], SAFE-UP [13], and LEAD [14], the practical application of digital twins have been used in various aspects of urban mobility, from the optimisation of logistics operations to predicting future autonomous vehicle crash scenarios.
The City of Aachen:
Aachen, a city in Germany with approximately 250 000 inhabitants, is one of the EU cities currently developing its digital twin. [8]. Located in western Germany near the borders of the Netherlands and Belgium, approximately 100 000 people commute to and from Aachen daily [9]. Aachen is home to Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, a technical college (Fachhochschule Aachen), and a research centre (Forschungszentrum Jülich), making it a hub for research and innovation, especially in engineering and information technology.
Aachen is at the forefront of digital transformation of urban environments. The municipality has established a dedicated digitalisation unit within its mobility and traffic department, responsible for overseeing projects such as the digital twin for urban planning [10]. These digitalisation efforts are closely aligned with the city’s sustainability goals, driving initiatives to reduce carbon emissions and promote green technologies. Notable projects in this area include GreenCityFollowUp [11], Project APEROL [12], and several others focused on advancing digital mobility solutions.
In action
The city of Aachen is developing a digital twin to create a more connected and efficient urban environment. This initiative is being driven by two key research projects: KomIT and VISTA, which together lay the foundation for a comprehensive digital twin that spans the city’s transport infrastructure and other urban systems.
“We have two major goals. The first is to build an urban data platform where we can bundle all the data we have in Aachen. And the second is the digital twin, which takes data from this data platform. We want to make the digital twin on, above and below the road.” (Dr. Michael Pielen, City of Aachen)
The data platform, initiated under the KomIT project [7, 15], acts as the central hub for all municipal data. It integrates data from various sources, including information on buildings, road infrastructure, trees, and even underground assets such as sewers and utility lines. This comprehensive data model is used for urban planning, asset management, and simulations that allow the city to anticipate and resolve potential issues before they arise. It enables stakeholders across different sectors to access and visualise critical infrastructure information in real time. This transparency enhances the decision-making process, reduces the chances of planning errors, and improves collaboration across city departments. Picture 1 illustrates a prototype of Aachen’s digital twin, providing a visual representation of road infrastructure.
Picture 1: Prototype of Aachen digital twin above the road. City of Aachen.
The model helps streamline construction planning, track the status of infrastructure projects, and make city development plans more tangible for citizens. Picture 2 provides an example of the digital twin’s capabilities, showing a detailed view of road infrastructure below the surface, which is crucial for long-term maintenance planning and optimising the lifecycle of city assets.
Picture 2: Prototype of Aachen digital twin below the road. City of Aachen.
In addition to general urban data, Aachen’s digital twin also focuses on improving the city’s transport network. The VISTA project [16] contributes data on the city's road network, traffic signs, road conditions, and more. Using 3D imaging and AI-powered analysis, the digital twin enables advanced traffic simulations and predictive analysis, helping to optimise traffic flow and reduce congestion. This transport-focused model covers Aachen’s 970-kilometre road network and allows for real-time updates, ensuring that the city’s mobility management is responsive to current conditions. As a result, city planners can test different traffic scenarios in a virtual environment, making informed decisions on traffic management, public transport, and even autonomous vehicle testing.
Results
Digital twins are proving to be a powerful tool for fostering cross-departmental cooperation within cities. By offering a unified platform that consolidates data from various sources, they provide a holistic view of urban processes, enabling more informed and coordinated decision-making. In Aachen, the initial benefits of this approach are already evident, with new collaborative projects emerging between departments such as mobility and climate adaptation.
Throughout the development of Aachen's digital twin, the importance of a well-defined data governance framework for regulating data management and usage became increasingly apparent. As the digital twin integrates vast amounts of real-time data from diverse sources, ensuring that this data is properly managed is critical to the twin’s accuracy and reliability. In response, the city is now prioritising the creation of such a framework to ensure compliance, security, and efficiency in data-processing activities, which are crucial for the successful operation of the digital twin.
The growing recognition of the need for enhanced data management highlights the value of a dedicated department to develop expertise specifically in data usage for the digital twin. Effective data governance ensures that the right data is collected, shared, and utilised across departments, enabling the digital twin to function as a powerful tool for urban planning and decision-making. In this context, the Data Spaces Blueprint v1.0 [18] provides valuable guidance on establishing robust data governance structures and ensuring interoperability. By using this blueprint, cities can shape their approach to ensure that their digital twin remains a reliable and integral part of city management.
Challenges, opportunities and transferability
As an early adopter of an urban digital twin, the City of Aachen is keen to share its insights with other cities, promoting collaboration and the exchange of valuable lessons learnt.
One of the key challenges in the Digital Twin Aachen project was encouraging various specialist departments within the city administration to share their data and make it available to other departments. Successful integration of the data required close collaboration between data owners. Continuously highlighting the benefits for all stakeholders proved to be a helpful tool to engage all stakeholders.
Another challenge involved establishing a clear legal basis for data processing. Determining which data should be published, especially from external entities like network operators, required careful examination of legal frameworks to ensure regulatory compliance. Additionally, the technical implementation of Aachen’s digital twin, which relied heavily on open-source programmes, raised important considerations regarding software availability, compatibility, and integration with existing systems.
Ultimately, digital twins have the potential to significantly improve urban management by enabling dynamic simulation and optimisation of urban processes. This can make cities more efficient, responsive to people’s needs, and foster communication between city departments. Digital twins are not only tools for urban management and planning but also central building blocks for the sustainable development and smart growth of cities.
In depth
[1] https://blog.ptvgroup.com/en/city-and-mobility/how-urban-digital-twins-…
[2] https://www.eiturbanmobility.eu/projects/digital-twins-for-smart-mobili…
[3] https://www.safe-up.eu/news/digital-twins-predict-future-av-crash-scena…
[4] https://living-in.eu/news/driving-climate-transition-digital-tools-and-…
[5] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52021SC0470
[6] https://commission.europa.eu/strategy-and-policy/priorities-2019-2024/e…
[7] https://bmdv.bund.de/SharedDocs/DE/Artikel/DG/mfund-projekte/komit.html
[8] https://www.aachen.de/de/wirtschaft_technologie/service/statistiken/zah…
_fakten/zahlen.html
[9] https://pendleratlas.de/nordrhein-westfalen/staedteregion-aachen/aachen/
[10] https://serviceportal.aachen.de/suche/-/vr-bis-detail/einrichtung/61602…
[11] https://bmdv.bund.de/SharedDocs/DE/Artikel/G/DKV/dkv-aachen-daten.html
[12] https://bmdv.bund.de/SharedDocs/DE/Artikel/DG/AVF-projekte/aperol.html
[13] https://urban-mobility-observatory.transport.ec.europa.eu/news-events/n…
[14] https://civitas.eu/projects/lead
[15] https://onion-innovation.de/2024/04/29/komit/
[16] https://fgsv-veranstaltungen.de/shop/praesentationen-kommunale-daten-20…
[17] IMMC.COM%282023%29751%20final.ENG.xhtml.1_EN_ACT_part1_v7.docx (europa.eu)
[18] Data Spaces Blueprint v1.0 - Blueprint v1.0 - Data Spaces Support Centre (dssc.eu)
[19] https://acumen-project.eu/
[20] https://omicronproject.eu/
Author: Clara Schneider
Views and opinions expressed are those of the author(s) and do not reflect those of the European Commission.
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