Last week, went to Jinzhou for an accident car inspection study, although only four days, but benefit a lot. The four days of time, ran through half of Jinzhou, basically the major brands of 4S store repair store is considered to have strolled all over.
To be honest, this trip down, it feels really shocking, not in those horrible accident scenes, but from the car itself has a new understanding of the safety.
When it comes to traffic accidents, they happen almost all the time, yet no one thinks they are the one who will be involved in an accident while we are driving, and often the more people ignore safety, the greater the risk of an accident.
I’ve seen too many accident scenes where the car is destroyed and not a few people are killed, either actively or passively, and it’s all a sigh of relief. After reading all of this, I can’t help but think-.
How much does so-called car safety protection really work?
In the automotive circle, in addition to the car test drive video, it is estimated to be the number of car crash test class of videos to attract the most attention. Watching these simulation tests, watching the car a little squeeze, watching the squeeze process dummy encountered various situations, and then look at a series of protection mechanisms to react to feedback, it seems that the brand’s crash test rankings are really quite convincing.
The weight of the car to protect the car in the end there is no role? Is the thin skin of Japanese cars a very low safety performance? Chevrolet has the highest accident rate in the world, is the car a safety hazard?
There are countless articles on this subject, but after spending so many days with accident vehicles and listening to mechanics recreate the crime scene of each and every one of them, I can’t help but wonder – is crash testing really reliable?
What exactly protects the passengers in the car?
Before examining the results of crash tests, let’s understand the basics.
Generally speaking, people often refer to a car crash as a “primary crash” and a human-vehicle interior crash as a “secondary crash”. For the human body, the risk of a collision is “inertial impact” and “car shocks” (this is a serious issue, some students do not think wrong ah), and the impact of a collision to a large extent affects the impact of the second collision on the human body injury.
Therefore, when considering the design of automotive safety and security, the car can be divided into two types of areas, namely, the passenger safety zone and the energy-absorbing buffer zone.
Passenger Safety Zone and Energy-Absorbing Cushion Zone
From the point of view of the occupants not to be deformed by the car crash resulting in crush injuries, the smaller the deformation of the occupant safety zone in the collision, the better.
To make the occupant safety zone deformation small, it is required that the cushioned energy-absorbing zone has a large overall stiffness, to be frank, it should be rigid to resist impact, but the cushioned energy-absorbing zone is too rigid, then the role of the cushioned energy absorption is small, poor energy absorption will lead to the body to accept the impact of the undiluted energy, that is, shock injury.
However, from the point of view of cushioning and energy absorption, the stiffness of the cushioning zone should be reduced.
The stiffness of the cushion should be small enough and the deformation should be large enough so that it can be strong enough to absorb the energy, which requires that the stiffness of the car design be tough rather than stiff.
This means that the junction between the energy-buffering zone and the occupant safety zone is designed to be more rigid, while the periphery of the zone is designed to be less rigid and more energy-absorbing. Due to the structural characteristics of the vehicle, the energy-absorbing zone has a poor resistance to side and top collisions, while the resistance to front and rear collisions is relatively good.
The so-called “soft exterior and rigid interior” is actually a combination of structural components and reinforcement. This is also the main device that protects our cars.
Difference between NCAP and IIHS crash tests
Crash testing is the evaluation of the results exhibited by a vehicle frame in a collision, assuming an accident environment.
At present, there are two international organizations: one is NCAP and the other is IIHS.
The NCAP crash test includes about two aspects, frontal and side impact.
The main ones are: frontal crash with 100% rigid wall at 50 km/h, frontal crash with 40% ODB (Overlapping Variable Barrier) at 64 km/h, side impact speed usually 50 km/h, as well as mid-pillar crash test and rear impact test. Crash test results are expressed in stars (★), which are five in total, with higher stars indicating better crash safety performance.
The IIHS crash test also includes two aspects: conventional crash and unconventional crash.
These include: front-end corner crashes, side impacts, roof strength tests, and the effects of rear-end collisions on the cervical spine. In addition to the basic tests, IIS also performs special crashes from time to time, such as vehicle-on-vehicle collisions to assess safety performance, and crashes into immovable solid walls at 128Km/h, which are very enjoyable to watch, but which have been met with discontent from some manufacturers.
The IIHS emphasizes front-end corner crashes and uses a “minimum acceptance index” for vehicle safety information. It is rated on a four-point scale of Good, Acceptable, Marginal, and Poor to provide consumers with authoritative information about vehicle safety.
The standards of these two organizations are actually tests of a car’s ability to absorb energy under stress. However, at a personal level, this boilerplate crash test is simply inadequate for evaluating traffic accidents in real-world road conditions in more complex environments.
After all, how many crashes are head-on collisions? And how many of the impacts would have been right on the side force reinforcement surface? Since it is a test that affects the level of life safety, at least some sincerity should be given, should be targeted at testing from the car’s weak points, which can only know what the extent of the vehicle’s short damage.
These days I see the accident car, most of them are not just a simple impact, mostly even collision, front and rear hit, overturned accident, accident environment can not be so simple as a test site, collision so single, just to the illusion of the nature of the collision test to prove a car safety coefficient, I can only hehe.
To give a few simple examples of accidents: this is the former with life for us to do the test!
Brand：Audi A6L
Accident type: primary front impact, secondary left side impact
Damage Level: A+
Repairs: almost no repair value, engine compartment parts almost destroyed, airbag and electrical components scrapped.
This is the beam head of an accident car, and we can note that there is no damage to the beam head itself.
From the inside of the impact surface, the front longitudinal beam is not twisted or deformed, but has some minor scratches, but the crash beam is broken into pieces.
This would have been the connection between the crash beam and the beam head, but as a result of the accident, the impact force was hypothetically deflected away from the longitudinal beam, resulting in the longitudinal beam, which is the most force-absorbing part of the vehicle, providing little protection and directly destroying components in the vehicle’s engine compartment.
The car’s primary impact surface was curved, and there was a supplementary impact on the side, presumably to avoid an oncoming vehicle that had hit a utility pole or tree.
Let’s take a look at the interior of this car-
In the photo, you can notice that the grain and bump of the front windshield is bulging from the inside out, which indicates that the glass was cracked by the airbag’s detonation. By the same token, the force of the blow on a human being is fatal, if not fatal, then feared to cause serious injury.
I once read a news article about a driver who was killed in an accident caused by an airbag that detonated. The airbag, which detonated like a miniature explosive, inflated instantly and shattered his ribs, causing the driver’s internal organs to be punctured by the ribs and he died from his injuries.
Therefore, the use of airbags is inherently dangerous, and relying solely on the protection of airbags will not protect people, but is more likely to hurt them. And this is exactly what we are going to talk about, the most important safety component – the seat belt.
As the driver’s first protection tool, the safety belt can be said in the accident to protect the role of human weight is the largest. Occurs the accident collision, due to the inertia reason, the human body will certainly rush forward, but the safety belt’s jamming technology can effectively protect the human body from the inertia influence, will people tie firmly in the seat.
As shown in the figure, the driver does not tie the safety belt, and this also means that when the accident collides, the human body will rush forward because of inertia, although it is not installed on the glass steering wheel, but the hard airbag is also enough to knock the driver unconscious. After the accident, the person in charge of maintenance introduced that the failure to tie the seat belt was also the main cause of the driver’s serious injuries.
Brand: Toyota Highlander
Type of accident: front and rear
Damage Level: B
Repair: Replace water tank frame and front face, left side fender needs to be replaced, left door sheet metal airbag and trigger module replacement, front windshield replacement, vehicle trunk needs to be cut and welded, rear door replacement.
The frame of Toyota Bully is still relatively strong, although it suffered a front and rear hit, but its damage is not serious, in this crash, the front longitudinal beam played a key role in protecting the main components of the engine compartment.
We can note that the front left side of the car is essentially shattered and the water tank frame is essentially scrapped, however, the engine and transmission are intact.
The rear impact appears to be heavily deformed, but in fact the force is mostly absorbed by the rear frame of the car.
The deformation of the car’s rear tailgate is relatively minor, and the front end of a vehicle capable of producing such a mid-cavitation impact should be relatively high.
The impact of the car looks complex, but it is a relatively routine impact, and the direction of impact is relatively positive, so it simply did not cause much damage to the driver, at this point, it can be said that the structural components and reinforcements of the car have shown the appropriate safety performance.
In the two cases above, we can see that in a conventional accident, a lower speed, larger impact surface, and a more direct impact would have caused little harm to the passengers. However, a faster, directionally deviated impact would have caused a more serious accident, especially if the two vehicles collided, which would have been more complicated and dangerous.
Crash tests have proven to be useful in that they can only show the ability of a car to withstand an accident under ideal conditions, but when it comes to the protection we can get from an accident, such data-templated crash tests are really of no use.
As for the thickness of the wagon, the weight of the car is bullshit. But whenever the collision, the wagon has no protective ability at all. And low-speed collision, basic will not endanger life and safety, evaluation of the safety of nature is also meaningless.
If it is a high-speed collision, a piece of debris may become fatal, and energy-absorbing car because of the soft frame, the body in the collision is more vulnerable, it is easy to squeeze the deformation. The car body of a harder car, the collision energy can not be absorbed, all the transfer to the driver and passengers, the consequences can also be imagined.
Therefore, in front of the real life crisis accident, any of your safety factor is how high the vehicle, the end is also into a pile of scrap metal, then talk about safety is simply meaningless.
Therefore, we must know that it is not the safety data that really protects our lives, but our good driving habits and cool heads.
As the safety advocate force says: when one person drives on the road, the whole family is worried, so maintaining good driving habits, not drinking and driving, not fatigued driving, fasten seat belts, this is the performance of responsibility to oneself and to the family.
As for the pencil pussies who are still arguing about this, go ahead and do whatever you want.
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