By Jerry F. Boone
Ten years ago, General Motors asked John Melvin to find ways to reduce driver injuries in open-wheel racing. His research helped revolutionize how CART cars are made today. Now he’s being asked to do the same thing in NASCAR.
The retired biomedical research scientist is a founder of the GM Racing Safety Program and the “black box” technology responsible for how today’s open-wheel cars are designed to protect drivers.
“I think we can do the same type of things for guys in NASCAR,” he says. “But that will depend on how NASCAR chooses to use the data.”
Early attempts at analyzing racing accidents yielded only limited results, available from analyzing photographs, videos, tire skidmarks and car wreckage. But beginning in 2002, each of the Winston Cup cars will be required to have the recorders, similar to those used in airplanes. The GM Delphi Automotive Systems boxes are used in Formula One, Formula 3000 and the Indy Racing League, while CART requires a similar system produced by Ford.
Today, a racetrack is the perfect laboratory to study what happens in an accident. In addition to the information from the black boxes, television is recording what happens on almost every inch of the track. By combining what the boxes tell them, what they see on the TV tape and relating that to the injuries to a driver, experts like Melvin can determine what happened inside the car.
The black box technology isn’t new. It is based on simple shock recorders first used to be sure that delicate electronic gears marked “handle with care” really were treated gently in shipping. Nor is it very sophisticated. Chances are the computer on your family car is far more complex and does much more work.
“The basic boxes are really nothing more than three accelerometers linked to a computer,” says Paul Stanecki, who brought Ford into the recording era with its “blue boxes” used in CART.
“Say you are in an express elevator and someone pushes the button to go to the top floor. What you feel when the elevator moves is acceleration. What the recorders do is take note of it.”
In addition to up and down movement, the boxes record acceleration side to side and front to back. The box monitors those movements constantly, but it isn’t until one of the accelerometers hits a spike of at least 20g’s that it will commit any of the data to memory, saving both the moments before the spike and also what happens after it.
“It gives about three seconds of data,” Stanecki says. “That doesn’t sound like much, but when you figure most accidents are over in about 30 milliseconds, it is plenty.”
Melvin, who began working for Ford, Chevrolet, Dodge and NASCAR late last year, says a trained eye can look at a graph of the impact data and relate it to what happened to the car when it hit a wall or another vehicle.
Stanecki is enthused about NASCAR’s new interest in chassis safety and driver protection. “It is the most popular form of racing in the nation,” he says. “It should be on the leading edge of development.”
Both men say it will require a different approach to making changes.
The chassis used in CART are almost identical, while those in NASCAR come from a variety of builders, each with his unique way of doing things. But that variety may speed development of driver-friendly cars, Melvin says.
“We will be able to look at similar crashes at similar speeds and angles and compare data that will show how different cars performed. Then we can look at how the cars were built to discover why one fared better than another and we can suggest ways to change them,” he says.
The basic construction is among the major differences between how a CART chassis and Winston Cup car is built. The stock car uses the traditional tube frame construction and is built to withstand multiple hits, keep running and score points. A CART chassis is made from carbon fiber and aluminum honeycomb. Parts shear off the tubs in a wreck, but the center “survival pod” surrounding the driver remains intact. Most crashes damage the car beyond what can be fixed in the pits.
In CART, the boxes are mounted as close to the center of the car as possible, and record the same type of motion and impact the driver feels in a crash. Using the black box data, the tub has been changed over the years to help absorb the impact and minimize injuries to drivers. The research has come up with simple changes like relocating some of the shift linkages to prevent leg injuries, and creating energy-absorbing collars that help keep a driver’s head in place, rather than having it be whipped around in an impact.
Stanecki says Winston Cup cars actually do a pretty good job of absorbing impact, but they also transfer too much of it to the driver. The researchers agree more-solid seats, with shoulder supports that don’t bend or deflect under load, are needed in the cars.
Melvin also says his early research for NASCAR indicates six-point harnesses can reduce both chest and neck injuries. He says the current five-point harness, with a single belt going between a driver’s legs, allows the driver to slip too far forward in a wreck, which creates slack in the shoulder belts.
It will be up to NASCAR to decide how much information it wants the black boxes to generate.
Glen Gray, Delphi’s engineering manager for motorsports, says the boxes can read things such as the rate of the car’s spin and have “external inputs,” which give information on the strain on the driver’s seatbelt harness and data on his head movement.
Melvin says he is working on a system that will put tiny accelerometers in a driver’s ear to study how violently his head moves in a crash. One of the goals is better helmet design and refinement of head and neck restraint systems.
The next generation of boxes probably will have more memory. They will be able to not only log the accident, but four, five or six laps before the accident, Gray says. It will allow them to see if the driver drove a different line, and determine if that had something to do with the accident.