LRO Propulsion System Testing

摘要

The Lunar Reconnaissance Orbiter (LRO) is a robotic exploration observatory launched on June 18, 2009. The LRO spacecraft contains a monopropellant propulsion system with twelve thrusters, two propellant tanks, a composite overwrapped pressurant tank, and fluid control hardware to regulate the propellant supply to the thrusters. This paper provides a detailed discussion of the testing process that verified the functionality of the system. Sections in this paper walk through the various component tests performed at the propulsion system level, including pressure transducer calibration, valve leakage tests, pressure regulator performance tests, and thruster gas flow impedance tests. Test descriptions provide test rationale, method and equipment, and approximate duration. This paper also includes descriptions of special propulsion tests, including heater verification testing, propulsion module vibration testing, and propulsion testing performed during the observatory-level thermal vacuum testing. This paper concludes with an explanation of the major lessons learned during functional testing, including intricacies associated with a system that includes diaphragm tanks and pressure regulator testing difficulties associated with a large downstream volume.