"Sivakumar has been promoted as Distinguished Scientist in recognition of his dedication and diligence in self-reliance effort for defence combat vehicle systems and sub-systems", an official release said.
He was involved in development of various products, including the Arjun MBT Mark-II, Carrier Command Post Tracked Vehicle, unmanned ground vehicles.
Sivakumar was also a fellow of National Academy of Engineering, the release said.