Today's headlines have no video, only graphics. Because I think that just one picture can support today's topic. Come, above:
Shocked? This is not a picture of the PS, this is a "stacking music" display planned by Volvo in China - on top of the head of one Volvo XC60, and then vertically stacked with another 6 XC60. The result is this scene that everyone sees.
This is an advertising shoot, in the advertisement, Volvo Car Group Global Senior Vice President, President and CEO of Asia Pacific Region Yuan Xiaolin, first sat in the bottom of the XC60 car, through the mobile phone and Chairman Li Shufu connected video, until the crane stacked to the top of the 6th car, Yuan calmly walked out of the car - yes, at this time, the door can still be opened normally.
The door can be opened, indicating that the amount of deformation is within a very controllable range. During the test, field professionals recorded the deformation of the roof of the "pressure car" by laser measurement comparison.
The result is that when the first XC60 is pressed on the roof, the roof height change value of the pressure car is slightly larger, 15mm; from the second car on the stack, the roof deformation gradually tends to be small, and after the 5th and 6th cars are stacked, the deformation is only 1mm.
After all 6 cars were stacked, they stood still for 24 hours, at which point the roof height was deformed by 25mm, and then after removing all the stacked cars, the roof deformation rebounded to 10mm.
Summary: After a day of "pressing the top" of 6 XC60s, the deformation of the XC60 roof was only 1 centimeter. At this amount of deformation, the integrity of the crew compartment is virtually unsightly harmful to the naked eye.
The above test obviously shows the pressure resistance of the roof (note that the bottom of the pressure car is supported by rigid columns, so the suspension and tires are not deformed, and all the pressure is borne by the body and roof).
What is the practical significance of the roof pressure resistance? The most obvious is safety in the event of a rollover. If a car is flipped to the sky on four wheels, the roof naturally has to bear twice the weight of the body itself; but in the process of rolling, the body also has the kinetic energy brought by speed, so in fact, the pressure on the roof in the overturning is not 1 times the weight of the car, but may be several times more.
That's why stacking one "self" is not enough, stacking several "selves" is enough to illustrate the problem. So how many of these "several" are enough cattle?
This is guided by scientific numbers.
In April 2010, IIHS in the United States introduced the first roof strength test in a crash laboratory environment. The test method was to use a large hydraulic machine to squeeze the roof beam on one side and record the amount of pressure applied when the amount of extrusion deformation reached 5 inches (127 mm).
Because each car has to bear its own weight when rolling over, the evaluation criterion of the roof strength test is to divide this pressure by the weight of the car, and the greater the pressure-weight ratio obtained, the higher the pressure standard.
The U.S. IIHS rating the strength of the roof is divided into four gears: Good, Acceptable, Marginal, poor, poor. Pressure-to-weight ratios above 4.0 are rated as Good, and below 2.5 are rated as Spot. According to IIHS data, vehicles with a pressure-to-weight ratio of 1.5 have a 50% higher probability of occupant death or injury in a rollover accident than vehicles with a pressure-to-weight ratio of 4.
In our domestic crash test, there is also an evaluation item of the roof pressure resistance, the evaluation standard is similar to IIHS, and the pressure-to-weight ratio is more than 4 to be rated as "excellent".
Back to the Volvo XC60, it scored a pressure-to-weight ratio of 5.18 in the IIHS roof strength test, which is a good level. Moreover, all Volvo cars have achieved excellent results in the IIHS test in the United States, and are the luxury brands that have won the highest safety rating of IIHS - Top Safety Pick+.
Of course, the test in the laboratory is only a known type of test, and the car with good test results is often difficult to escape the question of "test-taking education". But Volvo's emphasis on roof stress – or "muscle" – is much earlier than the IIHS's introduction of the relevant tests.
That's right, take a look at the following chart:
This is a print advertisement for the famous Volvo sedan "Back Truck" in 1988. The small print under the advertisement reads: The truck "carried" on the top of the 740GLE sedan weighed 6.75 tons.
There is also the following one, the more ancient "stacking music":
This is a 1982 Volvo 760 commercial, at the bottom of which is a 760 station wagon, and the result of this "Stacking Music" is six 760 sedans.
Unexpectedly, the original XC60's "stacking music" is completely an "outdated" old trick, and Volvo has been playing this for 30 years. If we assume that the action of "quietly carrying 6 of myself" can prove the excellent strength of the roof, then the roof strength of Volvo's products has actually reached the excellent level set by IIHS, China Insurance Research Institute and other institutions today as early as 30 years ago.
In fact, to say that Volvo is safe, it seems that there will be no controversy from senior car fans to car whites. But think about it, why does Volvo make such an impression? It's definitely not just from visually stunning ads like "Stacked Music". The passive safety of the car, although hidden inside, invisible to the naked eye, but once an accident occurs, it will be "alive" revealed, and it will certainly be untenable to show out of thin air.
Volvo's cars, with their reputation as "tanks on the road", on the one hand, stem from the brand's rigid and straight style for a long time in the past; more importantly, in countless real traffic accidents, Volvo has proved that its body is strong and impact-resistant.
How is this done? In the final analysis, it is the structure + material.
As early as 1944 – 15 years before they invented the three-point seat belt – Volvo adopted a cage body on its PV444 model. This body structure, which can disperse energy to all parts of the body in a collision, has proved to be the most effective occupant protection structure, and has laid the standard for the entire automotive industry.
Volvo in recent years on the new car a large number of boron steel as the main material of the body, stiffness, dosage are at the top level in the industry, but any study of Volvo's body materials through car dismantling and other ways, will give people a "no matter how much work" feeling.
This is the foundation for Volvo to establish a safe and secure image. Although this is a manufacturer's contract, Volvo's safety does have too many stories to tell (and the legendary "Miracle of Life Club", which can also be written separately when there is a chance), which is worth the industry and consumers often take out to study and think.
In reality, the accident is far more complex and harsh than the test, the development of automobile safety has no ceiling, I hope that today's topic can make everyone have a long posture on automobile safety and arouse more attention to safety. Talk about it next time!
222/1/7
Industry commentary
by YYP