TESS Vibration Testing: A Boundary Condition Case Study

The Transiting Exoplanet Survey Satellite (TESS) program is led by the Massachusetts Institute of Technology (MIT) Kavli Institute for Astrophysics and Space Research. The TESS payload consists of four identical cameras mounted to a composite plate and a data handling unit. Each camera consists of a detector assembly, a lens assembly, and a lens hood. TESS is currently slated to launch in March 2018 to begin a two year, all sky transit survey to detect exoplanets. MIT Lincoln Laboratory is responsible for the four cameras and the composite camera plate. As part of the environmental test campaign, Lincoln Laboratory conducted force limited proto-flight vibration testing at two distinct levels of assembly. As vibration responses were monitored at nearly identical locations during the two sub-system level tests, a variety of valuable assessments can be made regarding fixed-base vibration testing. As part of this case study, the effects of the boundary condition on the overall test article response are evaluated. This discussion addresses the effects of the boundary condition on the qualification of hardware against various failure mechanisms. Additionally, the advantages and limitations of force limited vibration testing are assessed.