Swarmlike collective behavior in bicycling

November 19, 2018, American Physical Society
The picture shows the peloton of the 2005 Tour de France on July 9 just out of Karlsruhe. Credit: Public Domain via Wikimedia commons

Whether it's the acrobatics of a flock of starlings or the synchronized swimming of a school of fish, nature is full of examples of large-scale collective behavior. Humans also exhibit this behavior, most notably in pelotons, the mass of riders in bicycle races.

During the American Physical Society's Division of Fluid Dynamics 71st Annual Meeting, which will take place Nov. 18-20 at the Georgia World Congress Center in Atlanta, Georgia, Jesse Belden, a researcher at the Naval Undersea Warfare Center, will describe the research he and his colleagues have been conducting on collective behavior in pelotons.

Using aerial video footage of bicycle races, Belden and colleagues analyzed peloton motion to determine what causes changes in the group's large-scale collective behavior. They found that move through the peloton in a manner similar to circulation in a fluid and observed two types of propagating within pelotons. "You see all these patterns and motion behaviors emerge," said Belden.

The found two types of waves affect the structure of a peloton. First, the researchers found a wave that moves back and forth along the peloton, usually due to a rider suddenly hitting the brakes and others slowing to avoid a collision. The other type of wave is a transverse wave caused when riders move to the left or right to avoid an obstacle or to gain an advantageous position.

Pelotons maintain a persistent structure, and researchers previously thought this form was driven by individual riders seeking an aerodynamic advantage. However, aerodynamics only come into play at the outside edges of the peloton. Instead, the researchers found that peloton dynamics are likely driven by rider vision, with each rider keeping other riders within a range of peripheral vision that is most sensitive to motion. Additionally, wave propagation speeds were consistent with human reaction time rather than conscious cognitive decisions like improving aerodynamics.

These findings shed new light on large-scale collective in humans and could apply to varied topics including traffic and crowd management. Additionally, understanding the role of sensory input in is important to building better autonomous vehicles like self-driving cars. This research has also given insights into the cognitive processes involved with individual rider actions and their effects on broader peloton dynamics. "Unlike birds or fish, you can talk to the cyclists," Belden said.

Explore further: New research may lead to a different strategy of cycling teams in escape attempts

More information: Presentation E17.5, "Continuum behavior in cycling pelotons" by Jesse Belden, Mohammad Mansoor, Aren Hellum, Andrew R. Meyer, Rafid Rahman, Christopher Pease, Scott Koziol and Tadd T. Truscott, will be Sunday, Nov. 18, 6:02 p.m. in Room B304 of the Georgia World Congress Center in Atlanta. Abstract: meetings.aps.org/Meeting/DFD18/Session/E17.5

Related Stories

How to win a Tour de France sprint

July 22, 2014

The final dash to the line in a Tour de France sprint finish may appear to the bystander to be a mess of bodies trying to cram into the width of a road, but there is a high degree of strategy involved. It takes tactics, positioning ...

Riding into research about cycle rage

September 4, 2015

Following a highly publicised 2012 incident on a mountain bike track in Canterbury's Port Hills, a Victoria University of Wellington academic has begun conducting research into cycle rage.

Minimising drag to maximise results

July 23, 2014

One of the most exciting parts of the Tour de France for spectators is the tactical vying for spots in the breakaway group at the front of the pack.

Fish in schools can take it easy

May 9, 2018

Using a new computer model, researchers at the Ecole Centrale de Marseille and CNRS have shown that a fish expends less energy when it swims in a school, because neighbouring fish produce a 'suction' effect. This work will ...

Recommended for you

Sculpting stable structures in pure liquids

February 21, 2019

Oscillating flow and light pulses can be used to create reconfigurable architecture in liquid crystals. Materials scientists can carefully engineer concerted microfluidic flows and localized optothermal fields to achieve ...

How to freeze heat conduction

February 21, 2019

Physicists have discovered a new effect, which makes it possible to create excellent thermal insulators which conduct electricity. Such materials can be used to convert waste heat into electrical energy.

Water is more homogeneous than expected

February 21, 2019

In order to explain the known anomalies in water, some researchers assume that water consists of a mixture of two phases, even under ambient conditions. However, new X-ray spectroscopic analyses at BESSY II, ESRF and Swiss ...

Correlated nucleons may solve 35-year-old mystery

February 20, 2019

A careful re-analysis of data taken at the Department of Energy's Thomas Jefferson National Accelerator Facility has revealed a possible link between correlated protons and neutrons in the nucleus and a 35-year-old mystery. ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.