All Volvo’s car models tested by the International Insurance Whiplash Prevention Group (IIWPG) were found to be in the best class. The Volvo Car Corporation was the only manufacturer to have their entire range achieve the best class rating.
“We are very pleased that the Volvo cars have performed in line with our expectations,” says Ingrid Skogsmo, safety director at the Volvo Car Corporation. “Tests only show a sliver of what happens in real life. However, this is one of several results that confirm Volvo has the right approach to help reduce neck injuries in rear impacts.”
The Volvo Car Corporation introduced Whiplash Protection System (WHIPS) in 1998. In the WHIPS system the entire backrest is designed to help protect the occupant’s neck in a rear impact. Today WHIPS is a standard feature in all Volvo car models, offering protection against the most common traffic injury.
“After having the system in our cars in real life traffic for six years now, the feedback from the Volvo Cars Accident Research Team shows that WHIPS has halved the risk of long-term neck injuries in rear-end impacts compared to prior Volvo seats. Independent field studies have also shown a significant injury reduction,” says Dr Lotta Jacobsson, technical expert in biomechanics at the Volvo Cars Safety Centre in Gothenburg, Sweden.
All in all 208 front seats were tested in the United States and Europe by the IIWPG to measure how the head restraints are designed and how they perform in a crash simulation where the seat is placed on a sled that reproduces a rear impact with a speed of 16 km/h.
Jacobsson is one of the people who have carried out in-depth studies of the factors that increase injury risks, and she has obtained her doctorate with a thesis titled Whiplash Associated Disorders in Frontal and Rear-End Impacts: Biomechanical Guidelines and Evaluation Criteria Based on Accident Data and Occupant Modelling.
Her doctoral thesis not only focuses on the factors that increase the risk of injury, but also offers guidelines for the development of protection systems.
The Volvo WHIPS system
The key principle when developing WHIPS was that both the entire spine and the head must be safely supported in a crash. Therefore Volvo cars did not only further develop the head restraint but also developed a supporting mechanism in the seat back.
WHIPS consists of both the high head restraint close to the head, a well-developed seat back structure in order to meet the moving body of the occupant effective and evenly, in combination with a built-in energy absorption in the joint between the seat back and the seat cushion.
In a rear-end collision, the seat back will move backwards with the occupant, first in parallel and then in a short reclining movement. The forces on the occupant will be reduced thanks to a deformation element where the seat back meets the cushion.