Mechanical Design of the Solar Probe Cup instrument on Solar Probe Plus

摘要

The Solar Probe Cup (SPC) Instrument is a Sun-facing Faraday Cup instrument slated for launch aboard the Solar Probe Plus (SPP) spacecraft in 2018. SPC is one of two instruments onboard the Solar Wind Electrons Alphas Protons (SWEAP) instrument suite and is the only SPP charged particle instrument that will not be shielded behind the spacecraft's Thermal Protection System (TPS). The 7-year SPP mission will take SPC on 24 solar encounters at perihelia ranging from 35 to 9.86 solar radii (R_s). The SPC components will encounter a large range of temperatures, from in excess of 1500℃ at perihelion to -130℃ at or near aphelion. This paper details the derived mechanical and structural requirements on the primary SPC mechanical assemblies including its thermal shield, the sensor unit and the strut/adapter assembly. An example of sensor requirements derivation to the component level is provided by the modulator flex ring. Preliminary requirements derivation, definition, and compliance are provided for these assemblies and components.