Sidney Adolph Horstmann, OBE (July 7, 1881 - July 11, 1962) was a British

British people

The British are citizens of the United Kingdom, of the Isle of Man, any of the Channel Islands, or of any of the British overseas territories, and their descendants...

 automotive engineer and businessman.

In 1913, Horstmann founded an automotive company that eventually became Horstman Defence Systems Ltd. He was responsible for developing a torsion bar suspension system known as the Horstmann bogie

Horstmann suspension

Horstmann suspension is a type of tracked suspension devised by the British engineer Sidney Horstmann in 1922.The system uses coil springs and has the advantages of a relatively long travel and, consisting of a self-contained bogie that is bolted to the hull, causing little or no encroachment on...

, which is used on many western tank

Tank

A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility, tactical offensive, and defensive capabilities...

s, including the Centurion

Centurion tank

The Centurion, introduced in 1945, was the primary British main battle tank of the post-World War II period. It was a successful tank design, with upgrades, for many decades...

 and Chieftain

Chieftain tank

The FV 4201 Chieftain was the main battle tank of the United Kingdom during the 1960s and 1970s. It was one of the most advanced tanks of its era, and at the time of its introduction in 1966 had the most powerful main gun and heaviest armour of any tank in the world...

. He patented this system in 1922, some nine years prior to Dr. Ferdinand Porsche

Ferdinand Porsche

Ferdinand Porsche was an Austrian automotive engineer and honorary Doctor of Engineering. He is best known for creating the first hybrid vehicle , the Volkswagen Beetle, and the Mercedes-Benz SS/SSK, as well as the first of many Porsche automobiles...

's similar system which was featured in many German tanks in the Second World War.

Sidney was the son of the German clockmaker Gustav Horstmann, who designed the world's first micrometer

Micrometer

A micrometer , sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw used widely for precise measurement of small distances in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier,...

with an accuracy greater than 1/10000 of an inch.