Hellfest, a lab to study crowd movements

June 2022. Helvest Festival is in full swing in Clemson, in the Loire Atlantic. On average, 65,000 spectators come every day to enjoy the beat of metal music. But this year the event has seen some extraordinary visitors. At the heart of the audience are two researchers from the National Research Institute in Digital Science and Technology (Inria) dancing for science. She is distinguished by her orange hats and suits filled with sensors. Written on their back: Hellfest & Inria collaborate here to study crowds. »

Sensor data combined with images taken by the camera from the stage allow it to monitor how the audience is moving. “At Hellfest, the dances are very physical. We seek to understand how people are connected and how those connections become movements that spread through the crowd., summarizes Julian Peter, researcher at Inria Rennes. The institute is conducting this study as part of the CrowdDNA project, launched by the European Union in 2020. The initiative brings together professionals in biomechanics, physics, cognitive science and computer science from several European countries. Their goal: to prevent accidents in large gatherings.

Crowd management is usually a manual processSorry, Julian Peter. The staff on site has a very partial view of the crowd. Several examples show that this misperception can lead to disasters. » Some have claimed tens of thousands of lives in musical, religious and sporting events over the past decades. The victims ran out of oxygen after overcrowding. Others lost their footing and were trampled on.

A stampede during a rally in Mecca in 2015 killed about 2,300 people. Most recently, on November 5, 2021, ten people were killed and more than 300 injured when concertgoers crowded the front of the stage at a concert by rapper Travis Scott in Texas.

human pendulum

For the seven CrowdDNA Project teams, spread across four European countries, understanding these phenomena begins in the lab. At a research center in Julliers, Germany, three people equipped with sensors were placed on a mattress on a mattress. An impulse is given to the individual at the back and propagates forward. Then the experiment is repeated with five, ten, thirty and fifty people. Human pendulums, like these aligned balls that transmit their energy to their neighbours, somehow. Except that the muscles of the body bring extra energy to the system. Thus, researchers note how a moderate flare can occur on a large scale.

You have 50.42% of this article left to read. The following is for subscribers only.