VEHICLE RESEARCH CENTER (VRC)

Crash tests conducted at the Vehicle Research Center in Ruckersville, Va. encourage auto manufacturers to make safer vehicles. The institute's vehicle ratings program has helped consumers pick the best models since 1995. Outside of automakers' proving grounds, few places in the world are equipped for the range of tests that we conduct here. Now, with the help of our insurance supporters, we are expanding the VRC so we can evaluate vehicle based crash avoidance systems. Our goal is to encourage adoption of the most effective technologies.

People on the observation deck watch as engineers inspect a car after a crash test.

CRASH HALL

The VRC's 22,000 square foot crash hall has three runways to accommodate front and side tests replicating crashes into another vehicle or fixed object. The cavernous crash hall can even handle tests involving a parked tractor trailer. We conduct 50-70 crash tests each year, and representatives from auto manufacturers are welcome to watch.

Apart from crashing real vehicles, we have used the runways to evaluate new technologies such as adaptive headlights and rear view camera systems.

We use specially designed crash test barriers when we evaluate how vehicles protect people in front and side impacts. In the moderate overlap front test, a fast moving vehicle strikes a deformable barrier made of aluminum honeycomb that crushes like a real car would in a crash. It's mounted to a larger barrier that's 320,000 pounds of steel and concrete.

In the small overlap test, we use a 5 foot tall rigid barrier with a radius of about 6 inches representing the outer corner of a car or a tree or post. The test vehicle strikes the barrier at 40 mph.

In the side evaluation, the test vehicle is parked and the barrier itself moves toward it at 31 mph. The 3,300 pound barrier strikes the driver's side of the vehicle. The barrier's face is shaped to simulate the typical front end of a pickup or SUV.

We also perform vehicle to vehicle crashes mostly for research purposes. An especially memorable crash test was the one we conducted for the 50th anniversary of IIHS.
The Sept. 9, 2009, crash featured a 1959 Chevrolet Bel Air versus a 2009 Chevrolet Malibu in a moderate overlap front test at 40 mph.

Beneath the crash hall floor is a propulsion system that can accelerate full size pickup trucks to 50 mph on the VRC's two 600 foot runways. Speeds up to 25 mph can be reached on a 200 foot runway situated perpendicular to the longer ones. The propulsion system, the first of its type in North America, uses compressed nitrogen to run hydraulic motors that, in turn, drive the cables that tow the vehicles to their designated impact speeds.

Before a side crash test, cameras are mounted on the opposite side of the test vehicle from where it will be struck to record footage from inside.

Just before the countdown begins for every test, bright light floods the crash hall. The lighting system provides up to 750,000 watts of illumination without glare, perfect for
capturing digital video and still images at multiple angles. Onboard cameras and additional ones positioned in the crash hall record the key footage that helps us assess vehicle performance and share the story with media outlets worldwide.

Photographers take detailed before and after photos of vehicles in a special studio equipped with a turntable that floats on a cushion of air to display vehicles from various angles.

The deformable barrier used in the moderate overlap front test is made of aluminum honeycomb.


CRASH DUMMIES

Nearly every crash requires a test dummy to help engineers understand what would happen to a person if they were in a similar crash.

So far, no single dummy is sufficiently humanlike to be used in all crash tests. IIHS uses three types of dummies for front, side and rear tests. We also have different sizes, ranging from a 6 month old infant to a 95th percentile man. A fully instrumented dummy costs about $200,000.


The Hybrid III 50th percentile male dummy (left) is used in frontal crash tests, the SID-IIs 5th percentile female dummy (center) is used in side tests, and BioRID 50th percentile male dummy (right) is used in rear testing.

Our workhorse dummy is the 50th percentile Hybrid III male. He's 5 foot 10 and weighs 172 pounds and is used in our frontal test programs.

SID-IIs is the dummy we use for side tests. It's the size of a 5th percentile woman or average 12 year-old child.

The dummy we use for rear tests is called BioRID. He has articulating vertebrae and reacts very much like a human would in a rear crash.

A dummy's sensors measure forces on and acceleration of the head, legs, feet and other body parts. Sensors also measure deformation of the chest. Engineers compare these measurements against values of stress and strain known to exceed the strength of human bones and tissues to determine how a real person might be injured.

Since dummies are made of metal and plastic, they must be calibrated to ensure they will react like a human would in crashes. Calibration is also important for consistency of results and ensures our dummies perform the same as dummies used in other test labs.

A little make up comes into play, too. Before each test, technicians apply greasepaint to the dummy's face, hands, knees and shins. During the crash, the paint rubs off wherever the dummy contacts the airbags, dashboard, doorframe or other vehicle parts. The telltale marks help engineers understand how the dummy moved during the test. The dummy's head has been known to move outside the driver window in some particularly poor performing vehicles, leaving paint marks on the barrier or striking vehicle.


Measurements from a dummy's sensors are logged by a data recorder (left) that is stored inside the dummy during crashes. The six sliding potentiometer sensors in SID-IIs (right) measure how far each rib is pushed sideways when the intruding door impacts the dummy's side.


TESTING LABS

Sled lab

Tests don't always involve crashing entire cars. Components like head restraints and car related gear such as child restraints can be tested on a sled that runs on fixed rails to simulate a crash.

The components are attached to the sled, and, for most tests, dummies are positioned in or on the components. Then the sled is programmed to create accelerations mimicking those in a vehicle's occupant compartment during the fraction of a second of a real world crash.

The sled can be programmed to simulate a range of crash types at both high and low speeds. This method is useful to study components whose performance in a crash wouldn't be influenced by the deformation of the vehicle itself. When crash forces alone are sufficient to evaluate a component, sled tests make sense because they're less expensive and easier to set up than full scale vehicle tests.

To test a vehicle seat for rear crash protection, the BioRID dummy is positioned on the seat which is mounted on the sled.


Roof strength testing

One important vehicle test conducted at the VRC doesn't involve any kind of crash, real or simulated. To measure roof strength IIHS uses a roof crush machine with hydraulic cylinders that press a metal plate into one corner of a vehicle's roof at a constant speed. The plate moves about an eighth of an inch per second. The maximum force sustained by the roof before it caves in five inches is compared with the vehicle's weight to find the strength-to-weight ratio. This is a good assessment of vehicle structural protection in rollover crashes.


Booster evaluations

The Institute evaluates booster seats at the VRC to assess which models are likely to provide good lap and shoulder belt fit in a range of vehicles. Engineers use a specially outfitted crash test dummy representing an average size 6-year-old child. For any given booster seat, the engineers measure how the safety belts fit under four conditions spanning the range of safety belt configurations in vehicles. Child restraint manufacturers sometimes try out new designs on our test fixture to see how their seats would rate.

Engineers prepare to measure safety belt fit on a child size dummy seated in a booster seat.


TEST TRACKS AND ROBOTICS

On the outdoor test track, IIHS has demonstrated the effects of antilock brakes and electronic stability control. Now, researchers are focusing on emerging crash avoidance technologies. Automatic emergency braking and pedestrian detection systems are two technologies being evaluated.

For these tests, researchers use an inflatable target vehicle that can be struck without damaging the test vehicle or a simulated pedestrian that moves across a vehicle's path via a pulley system.

In 2013, IIHS began a major expansion to accommodate more research on crash avoidance systems. The original 1,000 foot long track was expanded to allow more space for high speed maneuvers. A connector road will link the expanded track to a new 300 by 700 foot covered track.

When complete, the steel and tensile fabric structure will allow IIHS to run tests during the best and worst of weather. The open structure is designed to minimize interference with vehicle mounted crash sensors such as radar and camera systems.

IIHS is working with a robotics firm to develop new targets and vehicle controllers for an expanded crash avoidance test program. Robotic targets are needed because some of the new technologies we will be evaluating are meant to mitigate the severity of crashes but not avoid them. Our test vehicles need to be able to crash without striking a real vehicle.

A target is a lightweight dummy car made of foam or other impact friendly material affixed to a low platform and manipulated by a vehicle controller. Robotic controllers allow vehicles to be "driven" the same way each time to ensure repeatable test results.

 

 



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