Sperry was always interested in machinery, inventing at age six a horseradishgrater for his aunt. Later he studied machinery at various shops in his hometown of Cortland, New York, and made informal arrangements to sit in on lectures at nearby Cornell University. In recognition of his talents, the local YMCA collected money to send him to the Centennial Exposition at Philadelphia,where he was so awestruck with the mechanical marvels there that he said it influenced the rest of his life.
While attending Cornell, Sperry made suggestions concerning the constructionof a dynamo at the university that led to his being placed in charge of its building, as well as the development of a new type of arc light. At the age oftwenty Sperry founded the Sperry Electric Company, which manufactured dynamos, arc lamps, and other electrical equipment. The company was a success and was responsible for lighting systems in a number of cities, including Omaha, Nebraska, Kansas City, Missouri and St. Louis, Missouri. Sperry also attractedgreat publicity by building and installing the world's highest beacon on the390-foot (119 m) Board of Trade Tower in Chicago.
Sperry soon became interested in other mechanical devices. While visiting a coal mine, he observed the inefficiency of the labor used and decided to do something about it. He organized the Sperry Electric Mining Machine Company in1888, which designed and manufactured electrically driven mining equipment--electric chain cutters, electric generators, and electric locomotives for usein mines. Sperry later set up another company to manufacture streetcars for Cleveland. In addition, Sperry patented and built electric cars, devising a different kind of storage battery capable of taking a car 100 miles (161 km) ona single charge. He established yet another company to manufacture caustic soda, hydrogen, and chlorine compounds from salt. He later introduced a high-intensity searchlight, five times brighter than others available, which many countries had adopted it for anti-aircraft use in the military.
Despite these achievements, Sperry will always be best known for his invention of the gyrocompass. At the heart of this device is the gyroscope, a weighted, balanced wheel mounted in bearings and spinning at high speed. A key feature of a gyroscope is its ability to maintain its position no matter at what angle it is held. As early as 1851 the French scientist Jean-Bernard-Léon Foucault had predicted that the gyroscope might someday be used as a compass. Unlike the magnetic compass, which is confused by the steel ship hulls and electric systems on board these ships, the gyroscope remains undisturbed. In Sperry's gyrocompass, the gyroscope's wheel is part of the rotor of an electric motor, so that it spins at high speed. A weight on one side of the innermost ring responds to the Earth's rotation and forces the gyroscope to alignitself with the Earth until gravitational attraction holds it in place. Thus,the gyroscope assumes a north-south position, valuable for a compass, especially since the gyroscope points true north, not magnetic north as traditionalcompasses do (true north being the axis around which the Earth rotates).
Sperry used the principle of the gyroscope for two other key applications. First, he introduced a gyrostabilizer in 1913, a huge gyroscope mounted in thehull of a ship that resisted rolling from side to side. A destroyer outfittedwith one reduced a total roll of thirty degrees down to six degrees. In the1920s Sperry invented the first automatic pilot control for ships, named Metal Mike, which also used a gyroscope.
Sperry then moved to aircraft stabilization. At first, gyroscopes were used to control roll and pitch. When they sensed movement, the gyros activated compressed air, which acted on pistons to activate the aircraft controls. In later aircraft cockpits, pilots could use turn indicators, bank indicators, artificial horizons, and other devices controlled by gyroscopes. Today, gyroscopesform the basis for the inertial guidance systems prominent on submarines, aircraft, and rockets. During his lifetime Sperry held over 400 patents and founded eight manufacturing companies. Upon his death, he left the YMCA one million dollars to repay the organization for sending him to the exposition thatgave direction to his life.