Sarjaliikenne

Sarjaliikenne, in the Finnish transport context, refers to convoy or platoon traffic where two or more vehicles travel in a closely coordinated formation, typically on highways. The concept aims to improve traffic efficiency, reduce fuel consumption, and increase road capacity by maintaining small, uniform gaps between vehicles.

The operation of sarjaliikenne relies on coordinated driving, often supported by vehicle-to-vehicle and vehicle-to-infrastructure communications. Lead vehicles set the speed and braking profile while following vehicles adjust their acceleration and braking to maintain a short, safe headway. Advanced driver assistance systems, such as cooperative adaptive cruise control, play a central role in maintaining stable platoons and compensating for disturbances. The approach is commonly discussed in the context of automated or semi-automated driving, with the potential to integrate both human-driven and automated vehicles over time.

Benefits attributed to sarjaliikenne include improved traffic flow and capacity on congested corridors, reduced aerodynamic drag and fuel use for closely spaced trucks, and the potential for enhanced safety through standardized following distances. It can also enable more predictable travel times in certain traffic conditions.

Challenges and limitations include safety concerns in mixed traffic with human drivers, the need for robust and interoperable communication standards, and regulatory or liability questions. Infrastructure readiness, weather conditions, overtaking requirements, and the coordination of vehicles from different manufacturers are additional considerations. Privacy, cybersecurity, and data management are also important in the deployment of such systems.

In Finland, sarjaliikenne has been the subject of research and pilot projects by authorities and universities, with discussions focusing on highway corridors, technology requirements, and regulatory frameworks. It is not yet a widespread everyday practice, but ongoing studies aim to assess its feasibility and potential benefits in the Nordic transport system.