Search Results

The Inflatable Curtain (IC) has shown great potential to reduce head injuries in side impacts. This study explores and presents enhanced performance in two steps of improved activation algorithms. Crash data analysis, 21 full scale crash tests and component tests in a custom built drop tower rig have been performed. The IC performance in wider crash scenarios, including side impacts outside the occupant compartment (L-type impacts), was evaluated. Both statistical crash data and in-depth studies were used. It was found in the analysis of real life crashes that moderate to fatal head injuries can occur without intrusion in the occupant compartment. In L-type side impacts, the motion of the occupant relative to the vehicle interior may cause a head impact of sufficiently high severity to cause moderate to severe head injuries. A combined analysis of real world crash data and crash test results indicates that a substantial reduction in moderate to fatal head injuries can be achieved.

Neck injuries resulting from rear end car impacts have attracted increasing attention in recent years. Although usually not life-threatening these injuries can have long-term consequences. The exact mechanism of injury has not yet been established. Several probable mechanisms occurring at different phases during the crash sequence have been suggested by researchers. The accident experience with existing seat and head restraint designs is summarized. The results show that there are many factors influencing the risk of neck injury. A high and fixed-in-position head restraint, positioned close to the head, is beneficial. Also, Individual factors, such as gender and height, and seating position, are shown to have influence on the injury risk.

A positive trend to more frequent use of child restraint systems (CRS) in Sweden, during the last 20 years, is shown in this report. During the same period, the overall injury risk, for different age groups of child occupants, has decreased substantially. This indicates the high effectiveness of the child restraint systems. Children need car occupant safety systems specially designed for their size. This paper clearly states the need for child safety systems and discusses benefits and drawbacks with regard to different restraints, ages and injuries. The analysis points out, that when a crash occurs, the maximum effect of a child restraint system is not reached, if the child is not using the correct system for their size. There is even a tendency that the injury risk increases when children switch from one restraint system to another, i.e. are at the youngest ages for which the specific restraint is recommended. The background data used, is based on Volvo's traffic accident research.

The performance of three different six-year old dummies, the new Hybrid III six-year-old from First Technology Safety Systems, the Part 572 Subpart I and the TNO P6, was compared in a series of HYGE sled tests. The dummies were tested on aftermarket booster cushions in a Volvo 850 sled buck. Two different sled pulses were used: a Volvo 850 30 mph frontal crash pulse and an ECE R.44 pulse. The behavior of the dummies was compared for these two sled pulses. Motion analysis from high speed film was performed, showing the trajectories of the dummy heads. All dummies were fitted with triaxial accelerometers in the head, chest and pelvis. The Hybrid III was also equipped with a chest deflection transducer and Denton six-channel upper neck and five-channel lumbar spine load cells. The signals from a number of these sensors were compared.

Injuries in side impact collisions constitute one fourth of the serious or fatal injuries sustained by occupants in ordinary passenger cars. The Volvo Side Impact Protection System (SIPS) provides a substantially enhanced protection for car occupants in side collisions. The protection level of the SIPS system has been further increased by the addition of the Sipsbag, a quick-deploying side impact airbag system integrated in the seat backrest. The design of the non-electrical Sipsbag system is explained, as well as the advantages with a completely seat-integrated system. The process to industrialise the side airbag concept is summarised. Laboratory test results are discussed. Using methodology to correlate laboratory test data with accident data, an estimate of the injury-reducing effectiveness of the SIPS and Sipsbag system is made.

Recent cadaver studies have provided data for the development of force and stiffness characteristics of the side of the human head. A Hybrid III Anthropomorphic Test Dummy (ATD) head was modified to allow direct measurement of impact forces on the parietal and temporal regions by recasting the upper left half of the skull and installing triaxial piezoelectric force transducers. Dynamic impact tests of this modified head were conducted and force/stiffness characteristics for the temporal and parietal areas were compared to existing data on cadaver subjects. It was found that the existing Hybrid III vinyl skin satisfactorily represents the force/stiffness characteristics of the human head in these areas. This modified Hybrid III dummy head was also impacted against typical interior components likely to be contacted during a side impact. The force and acceleration test results are presented.

The level at which forces are transmitted from the striking vehicle in side impacts may influence the response of the struck car in several different ways. A better contact between the front bumper of the striking and the sill area of the struck car has been considered to be desirable in this respect. In side impacts, the most frequent direction of the impact is from 3 and 9 o'clock, while the direction of the forces is usually from 2 and 10 o'clock due to the velocity of the struck car. A European car and the EEVC moving deformable barrier have, therefore, been used in a crabbed mode to study the problem of load transfer at different levels above the ground. Volvo and Saab cars were used as targets in 55 km/h side impact with an APROD-81 side impact dummy placed on the struck side in the front seat. The results indicate that a difference in the level at which the loads were applied could influence the deformations, the kinematics of the struck cars, and the loading of the occupant.