Crash tests for safer trucks

An Audi A3 going 65 km/h collides head-on with the new Scania cab. But thanks to the truck’s underrun protection and the passenger protection system in the car, this collision may well not result in any serious personal injuries.

“Our extensive crash tests have resulted in an improvement of 5 km/h since Scania’s last cab launch in 2004, when the threshold for avoiding serious personal injuries was 60 km/h,” explains Lars Andersson, head of Testing and Simulations at the Scania Technical Centre.

Improved underrun protection

Among the reasons for the improvement is that the underrun protection system on the new cab front has better characteristics for parrying a head-on collision with a car. Crash tests reveal how the underrun protection system and its brackets behave in such a collision and how other vital functions in the truck are affected.

In head-on collisions between a truck and a car, the car may become wedged under the truck. This usually results in fatalities or severe personal injuries to the car’s driver and passengers. In addition, the truck may lose its steering ability and turn over.

“Our primary requirement for an underrun protection system is that it must prevent the car from driving under the truck,” says Michael Öman, passive safety expert at Testing and Simulations. “At the same time, the truck must retain its steering and braking ability.”

Physical crash tests

Before Scania carried out crash testing at Dutch research organisation TNO’s facility in Delft, the collision was computer-simulated over and over again by mechanical engineers at the Scania Technical Centre in Södertälje, Sweden. Only after this digital underrun protection system and its brackets had been deformed in a controlled way did Scania manufacture the prototype used in the actual physical crash tests.

Scania was the first heavy-truck builder to offer frontal underrun protection. It was launched in 1995 as standard equipment on Scania’s 4-series long-haul trucks. Later the European Union also realised the importance of such protection for people in passenger cars, and in 2003 a law requiring frontal underrun protection was enacted.

To ensure the safety and robustness of the cab structure, various crash and impact tests are carried out. The new R-series has a wider radiator that enables it to take in more cooling air, as well as a new front cab suspension. These new features had to be tested to ensure that they met both internal safety standards and legal requirements.

Impact tests subject the cab to powerful pendulum blows with predetermined energy levels from different directions.

“Scania cabs meet worldwide ECE R29 standards, as well as Sweden’s even tougher safety standards for truck cabs,” Öman explains. “The most important difference is that in the Swedish test, all three separate strength tests that are included must be carried out on the same cab.”