|Significant design||Developed the first gyroscopic device for steering a torpedo|
The gyroscope was invented by Leon Foucault in 1851 but industry ignored the device for nearly 50 years. In 1895 or 1896, Obry rediscovered Foucault's device and adapted it into a mechanism for steering a torpedo. This increased the weapon's accuracy from hundreds to thousands of yards. Obry then patented his device and sold the rights to Robert Whitehead, who incorporated the mechanism into the Whitehead torpedo. The device consisted of a bronze wheel weighing less than 1.5 pounds that was spun by an air jet.
Obry's device was notable for solving many problems; how to get the gyroscope to begin rotating as quickly as possible, how to direct the vertical rudders and how to maintain the fast rotation of the rotor.
- Aczel, Amir D. (2003). Pendulum: Leon Foucault and the Triumph of Science. Simon & Schuster. p. 171. ISBN 0-7434-6478-8.
- Bennet, Stuart (1979). A History of Control Engineering: 1800 - 1930. Peter Peregrinus, Ltd. p. 122. ISBN 0-86341-047-2.
- Stein, Stephen K. (2007). From Torpedoes to Aviation: Washington Irving Chambers & Technological Innovation in the New Navy 1876 to 1913. University of Alabama Press. p. 123. ISBN 0-8173-1564-0.
- Range, Shannon K'doah. "Brief History of Gyroscopes". Archived from the original on 2015-07-10. Retrieved 2013-05-28.
- "Torpedo of Rijeka: First in the World". Retrieved 2013-05-28.