Displaying items by tag: gyroscope

The Scalable SIRU™ is an inertial unit for spacecraft navigation system. It is commercialized by Northrop Grumman Corporation. 'SIRU' stands for 'Scalable Space Inertial Reference Unit'.

It combines innovation and high reliability. According to Northrop Grumman Corporation it records (July 2013) 100 percent mission success in more than 22 million on-orbit hours and 147 billion miles traveled—for precision performance on space missions.

The Hemispherical Resonator Gyro (HRG) sensor on the Scalable SIRU™ is composed of three simple machined quartz parts— an outer shell, a high-Q vibrating hemispherical resonator and an inner shell. The quartz construction of the HRG is inherently stable, impervious to aging effects, and naturally radiation hardened.

Applications: The Scalable SIRU™ is performing sensor pointing/stabilization and spacecraft attitude control on demanding long-term space missions. Each of the four inertial sensor channels can be operated independently by either of the two power supply/processors, providing a probability of mission success of 0.997 for a 15-year mission. 

The hemispherical resonator gyro (HRG) is a gyroscope technology, patented and commercialised by Northrop Grumman Corporation.

The HRG is used for military and commercial space applications. It recently achieved a major milestone of 25 million hours of continuous operation without a single mission failure.

Since February 1996, the HRG has been a vital component of Northrop Grumman's Scalable Space Inertial Reference Unit (Scalable SIRU™) and its predecessor, the Space Inertial Reference Unit (SIRU), which enable the stabilization, tracking and attitude control of spacecraft and satellites. The Scalable SIRU™ was instrumental in achieving the scientific objectives of several highly successful program missions, including MESSENGER, Deep Impact and Cassini.