Piezoelectric Active Spherical Shell Reflector for Space

Inhalt:
This paper is a follow-up to the paper presented at the previous conference, Actuator 2018. It aims at developing ultralight (areal density: 40 - 200 g/m2), foldable space reflectors that could be used in space telescopes (for imaging purposes), satellite-based LiDAR receiver and space antenna. The project discusses the main achievements over the past two years: The demonstrator consists of a spherical shell of diameter 200 mm and a radius of curvature RC = 2.5 m (instead of a flat plate of diameter 100 mm). The substrate consists of a passive layer of PET (thickness 175 µm) which has been preferred to PEEK for better surface quality, covered with an active layer of PVDF-TrFE of 5 µm. Two ways of application of copolymer have been investigated: spin-coating and spray-coating, and the material parameters of PVDF-TrFE are identified with various methods. Finally, the control authority of the mirror demonstrator is tested by a dynamic metrological system based on Laser Doppler Vibrometry (LDV) technique.