MODAL CORRELATION OF THE SOLAR TERRESTRIAL RELATIONS OBSERVATORY

摘要

The Solar Terrestrial Relations Observatory (STEREO) mission is part of NASA's Sun- Earth Connections program. The primary goal of the STEREO mission is to discover how Coronal Mass Ejections (CMEs) develop at the Sun, propagate in interplanetary space, and effect the Earth's environment. STEREO consists of two nearly identical Sun pointing observatories. Both observatories orbit the Sun with one observatory leading the Earth, and the other observatory lagging the Earth. The STEREO observatories will produce 3-D images of CMEs during their two year mission. The STEREO observatories will be launched stacked on a Boeing Delta 7925-10L launch vehicle in 2006. Delta II payloads must meet minimum stiffness requirements to prevent dynamic coupling with the launch vehicle. Launch vehicle requirements for payload stiffness and mass were a challenge for the 3 meter (10 ft) tall 2 meter (7 ft) wide observatory stack. A finite element model of the payload must be provided to Boeing so that payload/launch vehicle coupling can be evaluated. The finite element model stiffness must be verified with testing. This paper describes the modal and proto-flight vibration test and correlation of the test with finite element model predictions.