Ralph Teetor: The Blind Visionary Who Invented Cruise Control

Picture an interstate cutting through one of America’s flatter areas, stretching off into the distance with little traffic in either direction. You’re mid-way through a trip in an unremarkable rental car, and the next couple of hours call for some pretty tedious driving. No problem: You pull a stalk jutting off the steering column or push a few buttons on the steering wheel and take your foot off the accelerator. The car hums on at a steady speed.

The next time you use cruise control, spare a thought for Ralph Teetor, the original inventor of the system. Teetor’s breakthrough in 1948 would become one of the most widely used automotive technologies, the basic system for today’s hands-free, geofenced driver-assist systems, like Ford’s Blue Cruise or GM’s Super Cruise, and a stepping stone towards self-driving cars—and he engineered it despite being totally blind.

Teetor was born in Hagerstown, Indiana in 1890, about 60 miles outside of Indianapolis. He was one of those turn-of-the-century inventors who lived through the transition from horse-powered transportation to the rise of the early automobile. Many of the features of modern cars were developed earlier than you think; for instance, the first patent for a windshield wiper dates back to 1903, granted to Mary Anderson, who never actually ended up seeing a dime for her invention. Teetor wouldn’t develop cruise control until near the end of his working life, in the 1950s, but he began working on the idea as far back as 1930.

Born fully sighted, a childhood mishap with a knife took first one eye, then both. The first was a simple physical injury, the second a rare autoimmune condition called sympathetic ophtalmia, in which the uvea of the healthy eye becomes diseased following an injury or surgery on the other eye. (Louis Braille himself may have suffered from the same condition.) By the age of six, Ralph Teetor was fully blind.

In 1896, blindness was a significant disability, but Teetor was a particularly resilient child. His uncles were train men with their own business, the Railway Cycle Manufacturing Company, incorporated in 1895, which became the Light Inspection Car Company in 1900. (One uncle, Charles, was a railway car inspector and had invented a “cycle car” that could run the tracks, greatly speeding up the inspection process. In a few years, the car’s pedal power was replaced with single-cylinder combustion power.) With his uncles’ guidance, Ralph began learning how to machine metal into various shapes in the family workshop. Using only his hands to “see” the parts, he and his grandfather managed to build a simple gasoline-powered car when Teetor was just twelve years old. They’d take it out in the early morning before traffic started up, when the clattery gasoline engine wouldn’t startle the horses.

Hagerstown is a tiny town today, with a population under two thousand, and that figure hasn’t changed much since Teetor was a boy. He mapped the entire place out in his head, counting the footsteps between home and the stores, listening for the buggies and the occasional car when crossing the street. He never used a cane.

Upon graduating high school, Teetor applied to the engineering department of the University of Michigan. The school turned him down; it had no idea how to teach engineering to a blind student. Teetor could not read Braille, but he was determined to learn engineering. With the help of a cousin, he enrolled at the University of Pennsylvania. Despite misgivings from the faculty, he went on to become the university’s first blind graduate and even edited the newspaper of the engineering club. He’s on record as the first blind engineer in America.

Teetor learned by having books read to him and exploring engineering models with his hands. He could type accurately, so he wrote many papers, and between those, oral examinations, and hand-assembled models, he proved he had a strong grasp on theory as well as practice. Later, he’d return to the University of Pennsylvania to get his master’s degree.

While Teetor was in school, the family business had evolved from making railway inspection cars to becoming a supplier of hand-crafted engines and components. Now known as the Teetor-Hartley Motor Company, it sourced parts for automakers such as Stutz, Peerless, and Willys-Overland. Teetor worked at his relatives’ company for a few years before WWI broke out, after which he spent his war years in New York working for the U.S. Navy. There, Teetor solved a tricky issue with the Navy’s first steam turbine–powered destroyers, using his highly tuned senses of hearing and feel to develop a process to dynamically balance the turbines.

Post-war, Teetor went back to the family business. With Ford-style mass production putting a lot of the smaller, boutique car firms out of business, the Teetors realized that specialization was the key to survival. Teetor-Hartley Motor Company became The Perfect Circle Co., makers of piston rings, and their components made them a well-respected name in the automotive industry. (Perfect Circle was bought by Dana Holding Corporation in 1963.)

Ralph Teetor never forgot his love of a well-tuned engine. Indianapolis Motor Speedway was just up the road, and Teetor was a constant attendee. The racing teams got to know him well, and even asked him to help him set up their race cars. Teetor tuned engines by feel and sound for the likes of former fighter-pilot Eddie Rickenbacker. Over the years, he was named chief steward of the Indy 500, and even a track official, totally unheard-of for a blind person.

Teetor became the head engineer at Perfect Circle, but he was always tinkering with things beyond piston-ring production. He patented a hydraulic automatic transmission design in 1924, some fifteen years before GM’s Hydra-Matic introduced automatics to the masses. Constant trips to and from Detroit inspired his most famous invention.

The way the family tells the story, Ralph developed his early cruise control system because of Harry Lindey, a family friend and Ralph’s patent lawyer, who chauffeured him to Detroit. Lindey wouldn’t or couldn’t keep a constant speed when he drove, and the constant rocking back and forth drove Teetor up the wall. He began working on a way to invent something to keep a vehicle at a constant speed.

The earliest such device, patented in 1948, wouldn’t hold the throttle open to a certain position but rather stopped the pedal’s travel once a certain speed was reached. (It’s likely that wartime gas rationing and WWII’s national 35-mph speed limit were also factors in Teetor’s invention.) Further development of the device, which Teetor dubbed the Speedostat, eventually led to an electromagnetic lock that held speed constant.

The Speedostat was demonstrated to the press and many of Detroit’s automotive executives in the 1950s, even as Teetor refined it further. Chrysler was first to adopt the technology as a luxury option in 1958, and one year later Cadillac offered the Speedostat on its cars as Cruise Control. The name stuck.

Teetor lived to 91, and he never stopped tinkering. He served as president of Perfect Circle and of the Society of Automotive Engineers and, at his death, held over 40 patents for various speed control devices on cars, a knurling machine, a door latch, and a holder for fishing rods. He was inducted into the Automotive Hall of Fame in 1988, six years after his death. Next time you set the cruise control and stare out that windshield, think of the man who couldn’t see the horizon but never considered himself handicapped.