  We introduce "Moving Light": an unprecedented real-life crowd steering
experiment that involved about 140.000 participants among the visitors of the
Glow 2017 Light Festival (Eindhoven, NL). Moving Light targets one outstanding
question of paramount societal and technological importance: "can we seamlessly
and systematically influence routing decisions in pedestrian crowds?"
Establishing effective crowd steering methods is extremely relevant in the
context of crowd management, e.g. when it comes to keeping floor usage within
safety limits (e.g. during public events with high attendance) or at designated
comfort levels (e.g. in leisure areas). In the Moving Light setup, visitors
walking in a corridor face a choice between two symmetric exits defined by a
large central obstacle. Stimuli, such as arrows, alternate at random and
perturb the symmetry of the environment to bias choices. While visitors move in
the experiment, they are tracked with high space and time resolution, such that
the efficiency of each stimulus at steering individual routing decisions can be
accurately evaluated a posteriori. In this contribution, we first describe the
measurement concept in the Moving Light experiment and then we investigate
quantitatively the steering capability of arrow indications.
