Cruise control

Cruise control emerged because a blind engineer was annoyed by his lawyer's inconsistent driving—and invented a device to solve a problem he could hear but not see.

Ralph Teetor lost his sight at age five after a knife accident triggered sympathetic ophthalmia, destroying vision in both eyes. Despite his blindness, he graduated from the University of Pennsylvania with a mechanical engineering degree in 1912, becoming the first blind engineer on record in the United States. At his family's Perfect Circle Corporation in Indiana, he had built a working automobile at age twelve.

The inspiration came in 1936. Teetor was riding with his friend Harry Lindsay, a patent attorney. Lindsay had a habit of speeding up while talking and slowing down while listening. The lurching variations drove Teetor crazy. He couldn't see the speedometer, but he could feel every acceleration and deceleration. He began developing a device to hold automotive speed constant.

On August 11, 1948, Teetor filed his patent for a 'speed control device for resisting operation of the accelerator.' Early versions simply stopped the throttle pedal's travel at a set speed; later designs used an electromagnetic lock to maintain constant velocity. Teetor tried various names—Controlmatic, Touchomatic, Pressomatic—before settling on Speedostat.

The wartime 35-mph national speed limit and gas rationing had made steady-speed driving a patriotic duty, creating a ready market. Chrysler adopted the technology first, offering 'Auto-Pilot' as a luxury option on 1958 Imperial, New Yorker, and Windsor models. Cadillac followed in 1959, marketing the feature under the name 'Cruise Control'—the name that stuck.

Teetor earned over 40 U.S. patents during his lifetime. He was inducted into the Automotive Hall of Fame in 1988 and the National Inventors Hall of Fame in 2024. The technology he invented—a blind man's solution to an annoyance he could only sense—paved the way for adaptive cruise control, autonomous driving, and every subsequent automotive automation.