How do people avoid bumping into each other?

How do people avoid bumping into each other?

Understanding how personal characteristics affect our walking patterns.

Successful collision-free walking requires us to avoid still and moving obstacles, such as other people. While we walk, our vision helps us to anticipate and react to hazards in the environment (Patla, 1997). We are constantly taking in information about ourselves and our surroundings to avoid bumping into things (Gerin-Lajoie, Richards, & McFadyen, 2005; Hackney, Vallis, & Cinelli, 2013). “Collision avoidance” is a movement skill where we avoid potential collisions with obstacles and/or other people by adapting our walking pattern. Research shows that collision avoidance is made up of two main factors: visual information about the obstacles in the environment and adapting our own actions.

How do people avoid bumping into each other?

Previous research has mainly looked at collision avoidance using non-living obstacles such as poles and mannequins. Results from our lab have found that when non-living obstacles are replaced with human obstacles, people change their walking strategies to be more cautious (i.e., slower pace, more space between self and other person) (Hackney, Cinelli, & Frank, 2015). It is thought that these cautious behaviours are the result of human-like qualities that do not exist for poles and non-living obstacles. It is clear that people do not treat poles the same as other humans when avoiding collisions. For this reason, it is questionable whether we treat all individuals the same or if our avoidance strategies are different depending on the personal characteristics of the opposing person that we are interacting with.

How do people avoid bumping into each other?

The goal of Sheryl’s current research is to find out how personal characteristics (i.e., sex, age, size, etc.) of an opposing person influences our avoidance behaviours and walking strategies. Sheryl is curious to know if we treat larger-sized people differently than smaller-sized people; do we tend to avoid someone who is walking faster versus slower; can we recognize someone’s personality based on their walking sway, and do we tend to avoid angry walkers with more caution? These are some of the questions that Sheryl hopes to answer throughout her PhD to better understand collision avoidance.

Sheryl’s research will shed light on the factors that affect walking behaviours with other people and can be applied to future research in biomedical engineering, robotics, and crowd behaviour modeling. At the Lifespan Psychomotor Behaviour Lab, we are interested in understanding how people move around to avoid bumping into others, and if we treat other people differently based on personal characteristics. If you would be interested in participating in a study, please email Sheryl Bourgaize at or her supervisor Dr. Cinelli at


Gerin-Lajoie M., Richards C. L., & McFadyen B. J. (2005). The negotiation of stationary and moving obstructions during walking: Anticipatory locomotor adaptations and preservation of personal space. Motor Control, 9, 242-269.

Hackney A.L., Cinelli M.E., & Frank J.S. (2015). Does the passability of apertures change when walking through human versus pole obstacles? Acta Psychologica, 162, 62-68.

Hackney A. L., Vallis L. A., & Cinelli M. E. (2013). Action strategies of individuals during aperture crossing in nonconfined space. The Quarterly Journal of Experimental Psychology, 66(6), 1104-12.

Patla A.E. (1997). Understanding the roles of vision in the control of human locomotion. Gait & Posture, 5, 54–69.