Safety features were an afterthought in the early days of the automobile. Today, safety technology has evolved dramatically. Cars are technology-packed computers on wheels, designed to protect lives at all costs.
Automotive crash safety can be broken into two distinct phases. Originally, manufacturers focused mainly on passive safety features that protected the driver and passengers in the event of a crash. As those features became more common, we began to see more developments in proactive safety measures that worked to prevent crashes in the first place.
Passive Safety: Surviving the Impact
For the first few decades of automotive history, injuries were catastrophic and often resulted in death or serious injury. Because vehicles were built like rigid metal boxes, they would survive collisions, but occupants were thrown forward into metal dashboards and non-yielding steering wheels. Here are a few highlights in the evolution of passive safety features.
1927: Shatterproof Glass
In 1927, Ford made laminated safety glass standard on all its vehicles. Unlike regular glass, laminated glass is made of layers of glass held together by an interlayer. In the event of a collision, the interlayer keeps the glass from breaking apart, helping prevent lacerations that traditional glass windows could cause. Today, tempered glass and laminated safety glass are standard across modern vehicles.
1950s: Crumple Zones
Austrian engineer Béla Barényi invented the crumple zone concept in 1937. He later joined Mercedes-Benz and further refined this concept, as evidenced by Mercedes-Benz patent #854157 in 1952. Rather than making cars as rigid as possible, Barényi designed the vehicle’s front and rear sections to deform structurally upon impact. This absorbs the kinetic energy of a crash before it reaches passengers. While a crash between two cars with crumple zones may look scary, a car with crumple zones is significantly safer than one without them.
1959: The 3-Point Seatbelt
Before 1959, cars occasionally featured 2-point seat belts that crossed the passenger’s lap. These seat belts evolved from a concept by English engineer George Cayley, who developed them for use in early gliders in the mid-1800s. Edward J. Claghorn received the first seat belt patent in 1885 for a device designed to keep passengers in their seats in New York City’s horse-drawn taxis. Nash Motor Company was the first vehicle manufacturer to offer factory-installed seat belts in 1949. The feature faced consumer resistance, with many requesting its removal. A common myth held that it was safer to go without a belt and be “thrown clear” of a car in an accident. Lap belts kept occupants inside a vehicle during a crash, but they weren’t particularly effective at preventing injury. A high-speed crash with this belt would frequently fold passengers in half, causing severe internal and spinal injuries.
Volvo engineer Nils Bohlin revolutionized vehicle safety in 1959 with the 3-point lap-and-shoulder belt, a version of which you’ll find in modern automobiles. The 3-point belt secures both the upper and lower body and distributes crash forces across the upper body rather than concentrating them at the waist. Volvo recognized its life-saving potential and opened the patent to all competitors for free. This seat belt has saved millions of lives to date.
1970s–1990s: Airbags and Structural Reinforcement
American engineer John W. Hetrick experienced a single-vehicle automobile crash in 1952 while driving his 1948 Chrysler Windsor in rural Pennsylvania. He realized that his family would have been much safer if they had been cushioned from the dashboard during the crash, and drew up plans for a car airbag, which he patented in 1953. Auto manufacturers largely ignored this invention until after Hetrick’s patent expired. In the 1960s, inventor Allen K. Breed developed sensors that triggered airbag inflation, and by the 1970s, automakers began installing airbags in Buick, Cadillac, and Oldsmobile models. Ford followed in the 1980s, and by 1998, the U.S. government mandated airbags in new cars.
Seatbelt pretensioners gained traction alongside airbag development. This technology mechanically cinches the seat belt tight almost immediately after an impact, keeping passengers securely in position while airbags provide cushion to help reduce the risk of serious head and chest injuries.
Active Safety: Preventing the Collision
Now that cars had safety features to reduce fatal injuries, manufacturers turned to collision prevention methods. Surviving a crash was no longer enough; they wanted to support drivers and help prevent collisions.
1971: Anti-lock Braking System (ABS)
The anti-lock braking system (ABS) concept has its origins in the railway, aircraft, and motorcycle industries, dating back to the 1920s, and first saw limited use in automobiles in the 1960s. Mario Palazzetti of the Fiat Research Center patented an electronic version in 1971, called “Antiskid.” Bosch bought the patent and multiple manufacturers began adopting it. ABS monitors each wheel’s rotational speed. When it senses that a wheel is about to lock up and skid, the system adjusts brake pressure, allowing drivers to brake hard without skidding. By 1987, ABS was standard equipment on all Mercedes-Benz vehicles. ABS has been required on all new cars sold in the U.S. since the 2013 model year.
Electronic Stability Control (ESC)
Between 1987 and 1992, Mercedes-Benz and Bosch collaborated to develop the Electronic Stability Program to address reduced traction while driving. They took previous developments in traction control and stability systems to create a more refined system. ESC, along with ABS, became required by federal law in 2012 for 2013 and newer models with a GVWR (gross vehicle weight rating) under 10,000 pounds. The technology works by tracking the driver’s intended steering direction and comparing it to the car’s actual path. If the car begins to skid or spin out, the system kicks in to guide the car back on course.
Sensors and Cameras
If you do a simple search of new car models today, you’ll notice that many vehicles are now equipped with a multitude of camera-related technologies. Some vehicles are now equipped with technologies that provide 360-degree visibility around them.
- Radar: Often mounted in the front grille or bumper, radar calculates the distance and speed of vehicles ahead, regardless of weather conditions.
- Cameras: Cameras can be mounted on the sides of the car, but are often found near the rearview mirror. Front-facing cameras can also assist with reading road signs, recognizing speed limits, and identifying other vehicles and pedestrians.
- Ultrasonic Sensors: Positioned in the bumpers, these short-range sensors alert drivers to immediate blind spots or close obstacles.
These sensors and cameras laid the groundwork for Advanced Driver Assistance Systems (ADAS). Features like lane assist, which nudges your car back into the lane, and blind-spot monitoring, which warns of hidden vehicles, all rely on these technologies.
The Modern Era: Driver Monitoring
Even with all these safety features, there is one issue that technology can’t solve: human error. Distracted driving, drowsy driving, and medical conditions contribute to a large portion of modern traffic accidents. While technology can’t eliminate human error completely, it can certainly reduce its impact.
This brings us to the latest milestone in automotive safety history: Driver Monitoring Systems (DMS). DMS combines dashboard-mounted cameras with sophisticated artificial intelligence algorithms. Instead of scanning the road, these systems actively scan the driver for dangerous behaviors.
- Distraction Tracking: AI tracks the direction your eyes are looking. If the system detects that you’re looking away from the road for an extended period, it triggers visual and audible alerts to get you back on track.
- Fatigue Detection: By tracking facial expressions, head drooping, and blink rates, the vehicle can detect early signs of drowsiness and prompt the driver to take a break.
While modern vehicles do an incredible job of protecting you, no amount of safety features will override poor judgment behind the wheel. Automobiles will continue to advance in safety technology, but it is always important to stay proactive and practice defensive driving to stay as safe as possible.
Crash Safety Testing
There’s no doubt that safety features like airbags and crumple zones have saved many lives, but that’s only half the battle. Manufacturers not only have to design and develop life-saving features but also prove that these technologies work in real-world environments. This is where designs and ideas move from the studio to the crash-testing lab.
In the early days of crash testing, before and into the mid-1990s, researchers examined human cadavers to map out baseline tolerance levels for spine and skull impacts. During this era, scientists were still trying to understand the limits of the human body, but there was no safe or standardized way to do so. Eventually, John Stapp, an American Air Force colonel, strapped himself to rocket sleds to test the limits of acceleration and deceleration on his own body.
Thankfully, testing grew more sophisticated, and the industry turned to more reliable and ethical methods for data collection. This led to the rise of the crash test dummy, which was first developed by the Air Force to test ejection seats. General Motors took this idea and created what we know today as the standard for crash dummies.
Today, institutions such as the federal government’s National Highway Traffic Safety Administration (NHTSA) and the insurance-industry-backed Insurance Institute for Highway Safety (IIHS) provide consumers with standardized safety ratings through their crash-test programs.
Visit our Car Safety Information Center to learn more.
