Nowday's passenger vehicles are designed to be more safety than they used to be. Still, about 10,000 passenger vehicle occupants die in crashes on Malaysian roads each year. About half of the deaths occur in frontal crashes.
Since 1970s, the federal New Car Assessment Program has compared frontal crashworthiness among new passenger vehicles. This program, which involves 40 mph crash tests into a full-width rigid barrier, has been highly successful in providing consumers with comparative crashworthiness information. It also has been a major contributor to the crashworthiness improvements that characterize recent passenger vehicle models.
Full-width and offset tests complement each other. For Frontal Crash Test, crashing the full width of a vehicle into a rigid barrier maximizes energy absorption so that the integrity of the occupant compartment, or safety cage, can be maintained well in all but very high-speed crashes. Full-width rigid-barrier tests produce high occupant compartment decelerations, so they're especially demanding of restraint systems.
In offset tests, only one side of a vehicle's front end, not the full width, hits the barrier so that a smaller area of the structure must manage the crash energy. This means the front end on the struck side crushes more than in a full-width test, and intrusion into the occupant compartment is more likely. The bottom line is that full-width tests are especially demanding of restraints but less demanding of structure, while the reverse is true in offsets.
Video Overhead view of frontal offset test
The Institute began frontal offset crash testing in 1995. In the Institute's 40 mph offset test, 40 percent of the total width of each vehicle strikes a barrier on the driver side. The barrier's deformable face is made of aluminum honeycomb, which makes the forces in the test similar to those involved in a frontal offset crash between two vehicles of the same weight, each going just less than 40 mph. Test results can be compared only among vehicles of similar weight. Like full-width crash test results, the results of offset tests cannot be used to compare vehicle performance across weight classes. This is because the kinetic energy involved in the frontal test depends on the speed and weight of the test vehicle, and the crash is more severe for heavier vehicles. Given equivalent frontal ratings for heavier and lighter vehicles, the heavier vehicle typically will offer better protection in real-world crashes.
Rating Criteria
Overall evaluation (frontal): The three factors evaluated in the frontal offset crash test
— structural performance, injury measures, and restraints/dummy kinematics
— determine each vehicle's overall frontal offset crashworthiness evaluation. The order in which vehicles are listed depends on performance in side impact tests as well as frontal offset crash tests. Ideally vehicles should be good performers in both test configurations
— a double good. Head restraint and bumper evaluations influence the rankings of vehicles with otherwise similar overall crashworthiness performance.
Structure/safety cage: Structural performance is based on measurements indicating the amount and pattern of intrusion into the occupant compartment during the offset test. This assessment indicates how well the front-end crush zone managed the crash energy and how well the safety cage limited intrusion into the driver space. Intrusion is measured at 9 places in the driver seating area by comparing the precrash and postcrash positions of these 9 points. (The steering wheel intrusion is split into upward and rearward components to obtain a total of 10 measurements.) Larger intrusion numbers indicate more collapse of the safety cage. For more information about how these measurements are made and compared,
and
Injury measures: Obtained from a 50th percentile male Hybrid III dummy in the driver seat, injury measures are used to determine the likelihood that a driver would have sustained injury to various body regions. The measures recorded from the head, neck, chest, legs, and feet of the dummy indicate the level of stress/strain on that part of the body. Thus, greater numbers mean bigger stresses/strains and a greater risk of injury. For more information about how these measurements are made and compared,
and
Restraints/dummy kinematics (movement): Significant injury risk can result from undesirable dummy kinematics — for example, partial ejection from the occupant compartment — in the absence of high injury measures. This aspect of performance involves how safety belts, airbags, steering columns, head restraints, and other aspects of restraint systems interact to control dummy movement. For more information about how these measurements and judgments are made and compared,
Guidelines for rating restraints and dummy kinematics
Guidelines for rating restraints and dummy kinematics
Test verification
Verification ratings are based on 40 mph frontal offset crash tests conducted by manufacturers for vehicles meeting requirements established by the Institute. Manufacturers supply information on basic vehicle and test parameters, measurements of intrusion into the occupant compartment, injury data recorded on a dummy representing an average-size man in the driver seat, and video of the tests. Institute engineers review this information and rate vehicles based on the same evaluation parameters used for the Institute's frontal offset test. To ensure manufacturers' good faith participation, the Institute is conducting audit tests.
from my point of view this Frontal offset crash tests conducted by the Institute since 1995 have prompted huge improvements in how vehicles protect people in frontal crashes.Then manufacturers responded by changing the designs of their vehicles to improve frontal crashworthiness. The result has been a turnaround in the frontal ratings. Now virtually every current passenger vehicle design the Institute has evaluated earns good ratings.
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