Science and NASCAR. Few people recognize how intimately the terms are intertwined. But at the NASCAR Research and Development Center, NASCAR engineers work tirelessly using complicated scientific technology to bring safety initiatives to the sport and improve existing safety measures.
Steve Peterson, NASCAR's technical director since 1995, has been instrumental in the development and implementation of such safety features as the SAFER Barrier, head and neck restraints, improved seat belts, cockpit surrounds, seats and fire safety. His most recent work has been with the Car of Tomorrow, NASCAR's new race car that focuses on safety, improved performance and cost efficiency.
"Steve has been a leader in safety research for our sport," said Robin Pemberton, NASCAR vice president for competition. "His work and expertise are evident in virtually all of the safety improvements NASCAR has made over the past decade."
A critical component of NASCAR's research involves using computer modeling for crash simulation. NASCAR uses an explicit three-dimensional program known as LS-DYNA to evaluate vehicle structures and test safety improvements.
"You hear people throw around terms when they're talking about computer modeling," Peterson said. "A lot of them will talk about FEA, which is finite element analysis. LS-DYNA is quite different from a lot of these other programs. It is what is called a non-linear information program. That means that you're able to crush or impact structures and learn how these structures are truly going to deform rather than just flexing. An FEA program will just kind of flex, and you'll see a diagram with red, green, and yellow, whereas the LS-DYNA program is much more helpful to us because it'll help predict where failures are going to occur. It's much more sophisticated."
Peterson said that LS-DYNA testing was a major part of the development of the SAFER barrier, and information gained from working on that initiative contributed to innovations in the Car of Tomorrow.
"During the development of the SAFER barrier, we had the opportunity to crash about 14 different cars at very high speeds, up to 160 mph, in predictable scenarios. And if you're repeating that scenario every time, then you're able to compare car to car and different structural differences. Once all that was done, we had a huge baseline information database there so we could say, 'OK, here's how our current car crashes,' so when we looked to make improvements with the Car of Tomorrow, it was helpful to go back and pull that information on the current car and compare it with the Car of Tomorrow. Of course, we crashed it at high speed, as well."
The incident database is a continually growing bank of information that NASCAR uses as a research tool. Each week at the racetrack, meticulous measurements of the car are taken for comparison in the event that it is involved in an on-track incident.
"When a team presents the car for inspection, the driver's cockpit area, particularly the seat, is measured and documented," Peterson said. "We look at what type of belts he has, what style of belts, what the dimensions in the seat are, the headrest, and what type of personal safety equipment the driver wears. That's all done before the event starts that weekend. Then if it's the first practice session and the car goes out and has an impact, or if it's during the race on Sunday, then we have pre-event information and post-impact information. We can compare measurements and look at the components that they were wearing or using and see if there was any stresses or damages. That's all recorded in the database so that over time, we're able to build situational histories of what happens during impacts."
The safety inspection checklist contains more than 60 items, Peterson said. Once they are all checked off, a sticker is placed on the car indicating clearance to practice. But the safety inspection process doesn't end there.
"Our safety inspectors spot-check through the garage during the course of practice to make sure no changes have been made and drivers have all of their safety gear on at all times," Peterson said. "If there's an accident out on the racetrack and the car is brought in to the garage, the same group of safety inspectors will go over the car and look for changes, look for differences, take photographs, take measurements, read the data recorder, and help the team get the backup car inspected for getting back out on the racetrack.
"At the actual race, wrecked cars are brought into the garage and the same procedure is performed with measuring and photographing. So even if I don't go to the race, I'll have a good photographic history, video history, and measurement history of the car, and put that together with crash pulse [a trace of the change in acceleration over time] from the black box recorder and any medical information from the care center, and have a very concise report."
Black box data recorders, also known as accident data recorders, have been used full time in NASCAR's top three series since 2002.
"They give us an idea of how hard impacts are to the frame, to the chassis of the car," Peterson said. "We're able to go through and data mine the database to come up with trends and histories that would lead to new designs. That's basically how the Car of Tomorrow came about."