Simultaneous and sequential affordances of collision avoidance between multiple pedestrians

Laurentius Antonius Meerhoff (1) , Julien Pettré (2) , Richard Kulpa (1, 3) , Sean Lynch (1, 3) , Armel Crétual (1, 3) , Anne-Hélène Olivier (1, 3)

1 MIMETIC - Analysis-Synthesis Approach for Virtual Human Simulation
2 Lagadic - Visual servoing in robotics, computer vision, and augmented reality
3 M2S - Laboratoire Mouvement Sport Santé

Collision avoidance is an important aspect of human navigation. Previous research has shown how collision avoidance emerges in the case of pairwise interactions (e.g., Olivier et al., 2013). However, in many environments, collision avoidance encompasses more than only pairwise interactions. For example, a pedestrian navigating through a crowd has to avoid multiple pedestrians. It can be hypothesized that under some circumstances (increased complexity), the treatment of the interactions becomes sequenced: an agent first interacts with one (or several, but not all), and then with the next agent. In our experiment, a participant walked across a room whilst either one (i.e., pairwise) or two (i.e., group) participants crossed the room perpendicularly. By comparing these pairwise and group interactions, we assessed whether a participant avoids two upcoming collisions simultaneously, or as sequential pairwise interactions. Furthermore, in the group trials we varied the relative position of the two participants that crossed the trajectory of the other. This allowed us to change the affordance of passing through or around (i.e., its ‘pass-ability’). Results showed that in the group trials, participants consistently avoided collision with lower risks of impending collision (as quantified by the future distance of closest approach) in the group compared to the pairwise trials. This implies that a participant – to some extent – interacted simultaneously with two other participants. Furthermore, we analysed in the group trials how the ‘pass-ability’ evolved over time. Results indicated that the affordance of passing through or around was already established early in the interaction. This shows that participants are susceptible to the affordance of passing through a gap between others (cf., Fajen, Riley & Turvey, 2009). We concluded that pedestrians are able to interact with two other walkers simultaneously, rather than treating each interaction in sequence. Future work will address how robust these simultaneous treatments are in more complex situations

Mots clés: multiple interactions; Locomotion; collision avoidance

Domaines: Biomécanique [physics.med-ph]; Sciences cognitives

Laurentius Antonius Meerhoff, Julien Pettré, Richard Kulpa, Sean Lynch, Armel Crétual, et al.. Simultaneous and sequential affordances of collision avoidance between multiple pedestrians. ICPA 2017 - 19th biannual International Conference on Perception and Action, Jul 2017, Séoul, South Korea. ⟨hal-01646507⟩