Technische Universität Berlin

Safety in Bicycle Traffic

How joint research with local people can make hopping on a bike safer for everyone

Wake up, eat breakfast, and then into the saddle. For many Berliners, hopping onto their bike each morning to head to work is a standard part of their daily routine, often not given much thought. Cycling is beneficial to both our climate and our wallets, not to mention the environment. These are not the only reasons the City of Berlin is making an effort to promote cycling and develop its cycling infrastructure.

Unfortunately though, particularly in Berlin, cyclists frequently encounter dangerous situations as they must share the urban transportation infrastructure and, in some areas, quite narrow roads with cars, trams, and other road users. Motorists do not always keep the required minimum distance to cyclists and put them at risk as a result of their negligence and carelessness.

Scientific research shared with the public – project by ECDF professor David Bermbach combines theory and practice

David Bermbach is one of the roughly 500,000 Berliners who cycle every day. The junior professor at Technische Universität Berlin (TU Berlin) conscientiously rides his bike to his office on Campus Charlottenburg and therefore knows from his own experience about the needs and problems cyclists have in the German capital.

Even when exercising the utmost caution, cyclists are exposed to the danger of being grazed, harassed, or even caught in an accident by motorists. Surveys show that these dangers prevent many people from using their bike to commute or for recreation.

TU Berlin is addressing this issue in a citizen science project. Citizen science is form of open science in which research projects are carried out with the help of interested laypersons. “SimRa” short for “Safety in Bicycle Traffic” began in September 2018 with a project duration of three years. Using a smartphone app, data about near crashes and main routes of bicycle traffic are collected. The analyzed data can then be used to develop recommendations for transportation policy and urban development measures, which are then presented to political actors and city administrators.

Participants have the option of codetermination – an awareness campaign informs the public both of the project progression and the results. The aim: increased safety and an improved infrastructure for cyclists in road traffic.

It is important to the computer scientist that his research work benefit Berlin’s urban society

David Bermbach's personal experience contributed to the idea for the citizen science project. Bermbach has a doctorate in computer science and is head of a new academic chair at the Berlin Einstein Center Digital Future, a center for research on the digital transformation of society with the involvement of all four Berlin universities.

The “Mobile Cloud Computing” research group, which was established at the end of 2017 and is headed by Bermbach, studies the software design and experiment-driven assessment of geo-distributed IT systems in modern applications domains with a focus on data management systems and application architectures. He asked himself how he could combine his research with citizen science and a concrete research objective that would benefit Berlin's urban society.

The idea of making road traffic safer through the use of innovative digital technologies not only appealed to him; his team was also easily won over by this application-oriented research.

Researchers use the standard built-in sensors to detect routes and dangerous situations for cyclists

The aim is to obtain an overview of hazardous areas in the city and the accumulation of dangerous situations by collecting data. The City of Berlin already maintains records on accidents in which cyclists are involved. However, this data does not include “near crashes” and bikes are not equipped with sensors to record these occurrences.

These often occur when cars and trucks suddenly turn or overtake a cyclist, requiring the cyclist to slam on the breaks or swerve to avoid crashing. David Bermbach’s team developed a solution for recording these situations.

For the SimRa project, participants were sought to install an app on their phone and allow data about their rides to be sent to the researchers.

Initially, the project was restricted to Berlin. However, the researchers have since been able to recruit citizen scientists in Augsburg, Bern, Bochum, Stuttgart, and Pforzheim.

Every commercially available modern smartphone is capable of GPS localization and comes with a built-in acceleration sensor. The sensor allows the smartphone to detect when it is turned on its side and rotates the display from portrait to landscape format.

The researchers make use of these two features to evaluate both the route and dangerous situations, such as sudden braking, evasive action or a fall. After their trip, users are asked to categorize and annotate the recorded dangerous situations.

The SimRa project offers insight into improving urban bicycle traffic while remaining data compliant

It is easy for interested members of the public to participate. Users can download the app from all usual app stores and take off after reading the short instructions. In addition to giving you a feeling of having done something for the advancement of science, it also offers practical functions. The app displays useful information such as distance ridden, average speed, and other statistics. So-called "gamification" elements are also integrated into a well thought-out concept encouraging users to collect new routes.

The team places great emphasis on data protection and transparency regarding the use of the collected data. For this reason, data are initially only stored locally on the phone. After their ride, users can decide whether to transmit the information to the project team’s German server. Each ride is pseudonymized so that movement profiles cannot be created. Unlike the majority of private providers of smartphone apps, the team, as part of a public university, does not offer the app for commercial purposes or profit.

Inclusion of civil society is an important priority of TU Berlin

Together with relevant academic chairs at the University, such as those concerned with urban planning, and with the involvement of interested members of the public, the information is evaluated and results shared, for instance with the Berlin Senate Department for the Environment, Transport and Climate Protection. In a next step, political actors can introduce measures to improve bicycle traffic.

TU Berlin has set itself the aim of supporting research and teaching for the benefit of society. The approach of involving the public directly in research through citizen science projects offers the University the ideal opportunity to identify the needs of civil society through direct exchange and collect regular feedback from urban society. The University will continue to develop this path in the future.