It takes days for a safety team to prep a vehicle for a crash test that lasts mere seconds. “The number of required crash tests is increasing, so your flexibility is decreasing when you’re trying to navigate third-party test schedules. That’s why having in-house safety-testing capability was key for us,” said Chris Reed, regional senior vice president, research and development for Nissan Americas.
For the first time since the Nissan Technical Center North America (NTCNA) opened in 1991, the automaker has added a separate, sprawling facility to its Detroit-metro campus. The $40 million-plus Safety Advancement Lab includes a vehicle prep area, a crash-test dummy calibration room, photography pits to record vehicle impacts and concrete test-track lanes.
Tests are run according to requirements set by the Insurance Institute for Highway Safety (IIHS), the National Highway Traffic Safety Administration’s (NHTSA’s) New Car Assessment Program (NCAP), Federal Motor Vehicle Safety Standards (FMVSS), country-specific standards and Nissan standards. In a nutshell, the controlled vehicle crashes enable engineers to do in-depth analysis relating to vehicle, system and component crashworthiness.
During a lab tour with SAE Media, Mike Bristol, director of vehicle safety test engineering at NTCNA, said that physical tests help determine the robustness of vehicle and system designs. “There are always little differences between computer simulations and the actual physical testing, so having this safety center helps us get that perfect correlation that we want,” Bristol said. The 40-person safety lab crew of engineers and technical specialists can conduct 48 different crash test modes inside the 116,000 sq.-ft. (10,776 sq-m) building.
The safety lab’s two track lanes are partially separated by a wall. Depending on the testing protocol, a pole or a wall provide the impact barrier for a vehicle crashing at 35 mph (56 km/h) or another pre-determined speed. Other destructive vehicle tests include a forced rollover via a ramp, or a stationary vehicle being hit by a test cart. Standardized tests replicate side, rear, frontal and rollover accidents. “We cover a broad spectrum of crash situations by using various impact angles and speeds,” Bristol said.
Each track lane includes a high-speed digital camera photography pit that can be exposed when concrete slabs are removed and replaced with plastic acrylic panels. Overhead racks of high-intensity lights illuminate the pit during vehicle impact. “This safety center has one of the largest, if not the largest, photo pit of any crash facility in the U.S.,” Bristol said, noting that a crash can be captured by up to 23 different camera views at 1000 to 3000 frames per second. “We might add a few more high-speed cameras if there’s something special we want to focus on during a test,” he said.
Various vehicle components are spray-painted a specific color to help engineers identify the parts and systems during the crash. “The digitally recorded crash really helps design, performance, and safety engineers understand exactly what’s happening with the different components underneath the vehicle body as those components are deforming and breaking in a controlled manner during the collision,” Bristol explained.
The parallel test track lanes are flexible in terms of workflow, according to Bristol, noting that both tracks can be used on the same day, although not simultaneously. “It takes many hours to seat a crash dummy properly and get everything positioned correctly, including the cameras. The fact that we can do all of the necessary activities in parallel is the efficiency gain,” Bristol said. Having two test tracks also avoids the unwanted complications of having just a single track. “You might prep on one end while prepping on the other end at the same time, but really you’re just in each other’s way,” he said.
Facility construction began in 2020 at the beginning of the global COVID-19 pandemic. The first tasks involved digging foundations for the photography pits and the impact masses, which go down 13 feet. (3.9 m). “Our calculations show we used more than 800,000 pounds of concrete and steel for one impact mass,” Bristol said.
As the project progresses, big and small details need attention. When the supply chain, reeling from logistic and other pandemic-related issues, couldn’t produce insulated overhead garage doors, the team had to find an alternative solution. “Insulated doors are relevant because there are federal requirements that crash test dummies must be housed at a certain temperature range and humidity,” Bristol said.
Out-of-the-box thinking continues as the facility goes through its commissioning process. “Every test requires some type of creative solution to make it happen, and that’s what we’re working through right now,” Bristol said in late October 2021. “We’re at the phase of commissioning every single piece of equipment and we’re fine-tuning our processes.”
The new safety lab will test pre-production Nissan vehicles and production vehicles that the automaker manufactures in North America and South America. There also could be occasional assists for Japan production (Nissan in Japan has two safety labs.) In recent years, the number of required vehicle crash tests has been steadily increasing, according to Reed.
“Every couple of years we’ll see different crash modes,” he said, adding that the Michigan location can be expanded to accommodate new crash-test modes as those requirements materialize. The underlying performance driver for lab activities is consistency. Simply put, all static and dynamic vehicle testing needs to be repeatable. “Otherwise, the results are difficult to compare in terms of what’s safe and what isn’t safe,” Reed said.
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