Bike safety meets citizen science



By Harrison Tasoff, UC Santa Barbara

Commuting can be dangerous for a cyclist in town, says professor Trisalyn nelson knows it too well. One day, while cycling home from work in Victoria, Canada, a driver nearly cut her off. It was far from the first time she had had such a close encounter, and always in the same place.

“I was like, ‘if I die on my bike, it’ll be here,'” recalls Nelson, Jack and Laura Dangermond Chair in Geography at UC Santa Barbara. “And I went mad.”

His anger sparked the action. Nelson’s frustration that day inspired a project that would become an important aspect of his young career:, an international initiative to increase bicycle safety. The website allows cyclists to report problem areas.

“I called a bicycle safety researcher and told him about the idea,” Nelson continued. “And she said, ‘Trisalyn, this is actually a very serious problem. Only 20% of bicycle accidents are reported to official sources. So when the time comes to make cycling safer, planners often have no idea where to start.

Trisalyn Nelson Photo credit: UC SANTA BARBARA

It was a perfect problem for Nelson. She specializes in GIS, short for geographic information systems. GIS technology enables researchers to capture and analyze geographic information. These researchers are essentially data scientists who work with map data, Nelson explained.

His team has developed a website where anyone, anywhere in the world, can map a bicycle incident or accident, as well as report any hazards. In addition to promoting the website and encouraging people to use it, the project also involves analyzing the data to generate new knowledge on how to increase cycling safety.

Since its inception in 2014, has extended its coverage to 40 countries and has been translated into French, German, Spanish and Icelandic. The database now contains records of nearly 10,000 bicycle accidents, near misses and hazards. The project received approximately $ 1.5 million to support its mission, which allowed the team to expand to 15 people. has partnered with a number of cities, including Victoria, Ottawa, Reykjavik and Tempe, in search of better data to make infrastructure decisions taking into account the safety and accessibility of the bike. The team can combine their own data with official data sets to create maps of 10 to 25 bike safety hotspots that cities can then fix. They can also build statistical models to determine the factors that predict injury.

In addition to working with cities, Nelson and his team have produced several articles on citizen science and the causes of bicycle injuries. recently partnered with Outside Magazine to help elucidate the causes of bicycle deaths in the United States. Based on their research to date, the most dangerous situation for cyclists on the road is when vehicles are turning left.

“As a driver, there is a cognitive complexity involved in turning that leads to incidents and injuries,” said Nelson.

An important aspect of analyzing data is measuring exposure, or the number of people who cycle in a given area. “Studying safety without exposure is like studying COVID cases regardless of population size,” Nelson said.

The team uses data from Strava, a popular cycling fitness app, to map the number of people on bikes. Researchers developed statistical and GIS methods to convert the sample of Strava cyclists into cycling maps. These maps are essential for their research and also provide cities with important planning and management information.

Nelson and his team have just received funding for a new project, a participatory tool for the public to map micro-barriers to walking and rolling (and other types of mobility aids) in urban areas. “People will be able to map features such as uneven pavements that could impede the mobility of a person with balance issues,” Nelson said, “or places that need lighting to allow movement. safer at night. “

Having recently joined the UC Santa Barbara faculty after a tenure at Arizona State University, Nelson plans to expand’s presence in California. “The biggest obstacle to getting more people to ride – and reap all the health, economic and sustainability benefits of getting on their bikes – is a safety concern,” said Nelson. “So is really about overcoming barriers and creating healthier people and cities. “



Leave A Reply