抄録
Dimensional stability of space telescope structure is important to realize a highly performance observation. In particular, structures such as truss and spider arm to support optical components are required to maintain those positions with proper alignment. In order to satisfy the requirement in orbit, these structures are designed enough to be stable against thermal disturbance. In this paper, thermal displacement of truss strut was measured using built-in displacement sensor. Considering the requirement for the thermal stability, the specimens made of low thermal expansion materials (SiAlON and Super invar) were measured by the built-in sensor. The coefficient of thermal expansion (CTE) calculated from the measured thermal displacement was well matched with CTEs in test coupon. Therefore, the proposed self-sensing concept could be applicable nanometer-order displacement measurement of structural member having length over several hundred millimeters such as metering truss.
