Broadband vibration isolation in a deployable telescopic baffle exploiting post-buckling thrust tube dynamics

Stray light suppression is a primary consideration for high-performance optical instruments, yet the necessary baffle dimensions often conflict with launch volume restrictions. Existing solutions necessitate a trade-off: motorised telescopic mechanisms provide structural rigidity but incur significant mass, complexity and cost penalties. Flexible deployable shrouds, whilst volumetrically efficient, lack the deterministic geometry required for high-precision optical rejection.

Here, a passively deployable, rigid telescopic baffle designed to reconcile these requirements is presented. The architecture employs a nested carbon fibre reinforced plastic (CFRP) segment arrangement, actuated by a wire-driven mechanism and stabilised through built-in geometrical constraints and pre-tension. The conventional vane layout enables broadband optical operation, whilst the structure maintains a compact stowed footprint during launch. The specific topology, deployment kinematics and environmental testing strategy discussed in this paper pertain to the second generation of baffles developed for Vyoma GmbH’s space domain awareness (SDA) microsatellite constellations. They have an integrated design, including an opening protective lid and a supporting CFRP thrust tube that contains the optical instrument.

The thrust tube exhibits favourable metastructure properties under high excitations, effectively acting as an acceleration-limiting isolator for the telescopic structure during launch. The attenuation mechanism is high-frequency intermittent snap-through, with the thrust tube dynamically operating in a post-buckling regime. Qualification model vibration tests clearly demonstrate significant nonlinear broadband transmission loss, with no signs of structural or functional degradation detected a posteriori. Compared to a typical linearly behaving supporting structures, the current design maintains a vibration environment experienced by the baffle that corresponds to a substantially lower input level. A numerical approach contingent on a combination of traditional finite element analysis (FEA) and stochastic linearisation is proposed to enable accurate design-agnostic predictions of the phenomenon. Preliminary results indicate a strong correlation with shaker tests, confirming the viability of the modelling technique.