The capital of Finland first tested city modeling as long back as 1987. But the most recent model of the Kalasatama district demonstrates the new state-of-the-art possibilities of this technology: creation of a highly accurate digital twin of the city.
My hosts, Helsinki’s
city modeling specialists Jarmo Suomisto and Enni Airaksinen, showed me their
latest projects. One of them offered a glimpse of history through a lens of the
future.
With 3D glasses on, I was able to experience the unrealized city plan made by Eliel Saarinen, the father of the world-renowned architect Eero Saarinen. The virtual model in question was a digitized version of a huge physical model from 1915. Being able to stroll the streets and fly over the roofs of the imagined city really made me understand how awesome the original design was. I had seen a scale model of this same plan while it was laid in the foyer of the Museum of Finnish Architecture many years ago, but this experience was quite different.
The makers
of the virtual Saarinen model, the Helsinki 3D+ team, used the same technique
as they would use with a real-sized city. They took 3000 photos and programmatically
turned them into a point cloud and further into a triangular mesh. In the case
of digitizing the real Helsinki, an airplane took over 42,000 pictures at 1.2
kilometers height, all with astounding accuracy. The length of a pixel in those
photos equated to 7.5 centimeters (3 inches) on the ground.
The Helsinki 3D+ Team
Helsinki
3D+ is an ICT development project that was started in 2015. It is now a
full-time job for a team of three mavens.
Architect Jarmo
Suomisto and Kari Kaisla have
jointly over 60 years of experience in 3D modeling and geospatial information
management. Kaisla created the first comprehensive model of Helsinki back in
2001. Enni Airaksinen, City Model Specialist and MSc, joined the team recently
after graduating from the Aalto University. She’s one of the few CityGML
specialists in Finland.
Helsinki
3D+ is not a traditional city survey or planning service. It is a tool that can
collaborate across all multiple functions of the city for whenever the use of a
city model could provide value. Suomisto mentions education and social services
as two examples. “City models are not just PR. They have a role to play in
solving universal urban problems,” he says.
The Kalasatama Project
Kalasatama is a new seaside district being developed in Helsinki. A smart city project called Fiksu Kalasatama has been experimenting with smart services in collaboration with the residents, businesses, and other stakeholders in the area. Helsinki 3D+ and Forum Virium, an innovation unit of the city, joined forces to serve the needs of the experimenters through the development and use of digital twins.
The Kalasatama
digital twin project got funding from KIRA-digi, the national digitalization
program of the Finnish government. The project team worked full time for over a
half year to complete five critical tasks, namely to:
- Create digital twins of the
Kalasatama development. - Share the models as open data.
- Provide a virtual platform for the
experiments that are part of the Fiksu Kalasatama project. - Test new technologies, especially
those related to CityGML. - Advance the use of digital twins in
the city’s processes and services.
“We created
two city models, for which we used the very latest technologies available. The
first one is a triangular mesh that is more detailed than the comprehensive
Helsinki model. The other is a CityGML model. We included several new themes,
like planned buildings and bridges,“ Airaksinen explains. “It is possible to
expand the same processes to cover the whole city in the future.”
CityGML is
a global standard established by OGC (Open Geospatial Consortium). It is a
semantic, expandable information model that can describe objects—e.g.,
buildings and building parts—and their relationships in a hierarchical
structure. CityGML makes the model “intelligent,” rather than just a three-dimensional
representation of the reality.
Digital
twins are also a hot topic in building construction and operations. Combining
city and building digital twins in the same model would make sense, but is not
straightforward. Current BIM and GIS standards don’t support this union, and
Suomisto predicts it may take years before it happens.
One of the key results from the KIRA-digi project was the documentation of the model creation and utilization process. The project team have described the process and use cases in a comprehensive project report that is going to be made available online, both in Finnish and English.
Many Uses
“Our
primary purpose was not to create virtual entertainment or pretty pictures. Our
aim was to increase the understanding of various phenomena and issues; to
simulate, anticipate, and optimize,” Suomisto proclaims.
Because the
digital twin data is open for anyone to use, the city and businesses alike can
create new services based on it. Helsinki’s Energy and Climate Atlas, for
example, uses the million semantic surfaces of 80,000 buildings to calculate
and visualize the city’s solar energy potential.
My hosts
also showed how they used digital wind analysis software to assess the effect
of wind on the high-rise buildings of Kalasatama. The software can replace
costly wind tunnel analyses and is already used in the auto industry.
Helsinki
3D+ had earlier created a portal to visualize Kalasatama development projects.
Citizens could study the area in 3D and add feedback with a mobile device. The
same system is now used in other projects as well.
“What we’ve done here in Helsinki has aroused interest in cities around the world. We’re facing the same challenges of climate change and the quality of life as they are, “says Suomisto. “We’re not competitors in a business sense. Instead, we’re networking and collaborating with other cities and sharing our work with open data standards and open source tools with everybody.”
To learn more about Helsinki 3D+ and to experience the city models, visit https://www.hel.fi/helsinki/en/administration/information/general/3d/3d
UPDATE: You can now download the report The Kalasatama Digital Twins Project.
The images are courtesy of the city of Helsinki.
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