Utrecht crowd simulation software enters market

Marc van Kreveld
Marc van Kreveld

Utrecht University’s own Dr. Roland Geraerts and Prof. Marc van Kreveld will develop a crowd simulation engine for game developers and companies specialised in simulating large flows of people. They have recently received a grant of 150,000 Euros from the STW technology foundation’s Demonstrator Programme. The simulation software developed by the computer scientists in Utrecht is much more advanced than the packages currently available on the market. In a conjunction with consulting and engineering bureau Movares the software was used by the city of Utrecht to prepare for the start of the Tour de France.

Crowd simulation software is increasingly utilised to prepare for situations in which large flows of people will have to be organised and controlled. These include events such as Coronation day, construction work on a large train station or an emergency at a football stadium. The software developed at Utrecht University is capable of rapidly calculating the effect that the placement of stages, fences, toilets, etc. would have on the flow of people, or what happens if 10,000, 20,000 or 30,000 more visitors come to the event. With the grant from STW, they will be able to expand their software with the results of their most recent research and adapt it to fully integrate with current software systems, including the popular game engine Unity3D.

One million characters

Utrecht’s crowd simulation software is built in such a way that a single PC can simulate more than one million characters. The commercially available crowd simulation does not support that. The software developed in Utrecht is also better at simulating the characters’ real-time reactions to adjustments in the surroundings than the ‘state of the art’ simulation software, or even the best computer games.

Roland Geraerts
Roland Geraerts

Five steps

The exceptional performance of the crowd simulation software produced by Utrecht University is the result of a clever organisation of the calculations in five separate steps. Each step zooms in to a level of greater detail. This saves considerable calculation time, and it makes the system extremely flexible. “For every change to the surroundings, the system only has to calculate the local effect of the changes. This makes our system much faster and the crowd reacts immediately to these changes”, explains Dr. Roland Geraerts of Utrecht University.

More realistic results

The system is also unique in that it uses walkable surfaces instead of walkable lines. With walkable lines, it is difficult to prevent collisions and social behaviour, such as groups of people who walk together. Surfaces, however, lend themselves well to these types of calculations. Utrecht’s crowd simulation software therefore provides much more realistic results.

Large areas

Another advantage to the crowd simulation software from Utrecht is that the areas need not be limited to a single building or festival area; entire city neighbourhoods can be simulated. The environments can be simulated in two or three dimensions, allowing for simulations of large festival areas or entire cities, but also 3D infrastructures such as football stadiums or airport terminals.

STW Demonstrator project

Technology Foundation STW finances excellent technical and scientific research and promotes activities for the application of research results in accordance with its mission. Under the motto: “Technology seeks user”, STW has set up the valorisation instrument Demonstrator. A Demonstrator project facilitates the introduction of a technology to the market.

More information

Press release about the use of Utrecht’s crowd control software for the Grand Départ in Utrecht.


  • Dr. Roland Geraerts, “Virtual Worlds” researcher, Departement of Information and Computing Sciences, R.J.Geraerts@uu.nl, 030 - 253 3977, 06 – 28 80 49 01
  • Monica van der Garde, press officer Faculty of Science, m.vandergarde@uu.nl, 06 13 66 14 38
  • Nieske Vergunst, press officer Faculty of Science, N.L.Vergunst@uu.nl, 06 – 24 90 28 01
  • Gaby van Caulil, head Communication & Public Affairs Technology Foundation STW, g.vancaulil@stw.nl, 030-6001 298