US engineer who developed various devices using gyroscopes, such as gyrostabilizers (for ships and torpedoes) and gyro-controlled autopilots.
The first gyrostabilizers dated from 1912, and during World War I Sperry designed a pilotless aircraft that could carry up to 450 kg/990 lb of explosives a distance of 160 km/100 mi under gyroscopic control – the first flying bomb. By the mid-1930s Sperry autopilots were standard equipment on most large ships.
Sperry was born in Cortland County, New York. He set up his own research and development enterprise 1888, then formed a mining-machinery company and, moving to Cleveland, Ohio, in 1893, developed and manufactured trams. He was president of the Sperry Gyroscope Company until 1926.
Sperry's first invention was a generator with characteristics suited to arc lighting. He produced a superior storage battery (accumulator), teaching himself chemistry in the process. He was also active in internal-combustion engine research and developed ways of detecting substandard railway track.
Sperry's gyrostabilizer, patented 1908, mounted the gyro with its axis vertical in the hold of the ship. The axis was free to move in a fore and aft direction, but not from side to side. He used an electric motor to precess the gyro (tilt its rotor) artificially just as the ship began to roll. The gyro responded by exerting a force to one side or the other. Since it was fixed rigidly to the ship in the plane, the ship's roll was largely counteracted.
Sperry introduced many of the concepts now common in control theory, cybernetics, and automation.