Abstract

This paper investigates a novel design approach for a vibration isolator for use in space structures. The approach used can particularly be applicable for aerospace structures that support high precision instrumentation such as satellite payloads. The isolator is a space-frame structure that is folded in on itself to act as a mechanical filter over a defined frequency range. The absence of viscoelastic elements in such a mounting makes the design suitable for use in a vacuum and in high temperature or harsh environments with no risk of drift in alignment of the structure. The design uses a genetic algorithm based geometric optimisation routine to maximise passive vibration isolation, and this is hybridised with a geometric feasibility search. To complement the passive isolation system, an active system is incorporated in the design to add damping. Experimental work to validate the feasibility of the approach is also presented, with the active/passive structure achieving transmissibility of about 19dB over a range of 1–250Hz. It is shown here that the use of these novel anti-vibration mountings has no or little consequent weight and cost penalties whilst maintaining their effectiveness with the vibration levels. The approach should pave the way for the design of anti-vibration mountings that can be used between most pieces of equipment and their supporting structure.

Highlights

  • For space launch vehicles, it is essential to isolate the vibration of aerospace structures to prevent damage to the payload

  • Following on from this work, the present study investigates the use of a folded space-frame structure as an antivibration mounting

  • A Darwinian–Lamarkian hybrid approach [13] was taken to ‘repair’ infeasible geometries when discovered throughout the routine using a gradient-based sequential quadratic programming (SQP) search of an algorithmically differentiated implementation of the feasibility metric Eq (6) [14]

Read more

Summary

Introduction

It is essential to isolate the vibration of aerospace structures to prevent damage to the payload. The structure was optimised based on energy flow analysis models and relied on the wavelengths of the vibrations of interest being of a similar order to the changes introduced into the geometry of the structure during optimisation [8] Because of this limitation, an active control system was used to control the lower frequency vibration. The computational design of a passive structure [9] is combined with co-located ‘sky-hook’ damping [10] into a compact vibration isolation mount with improved ease of assembly [11]. The design is tested dynamically to demonstrate the significant attenuation afforded by the combined passive and active elements This novel concept may represent a new type of lightweight and cost effective anti-vibration mounting designs.

Isolator construction method
Geometry feasibility
Passive structure design methodology
Active element design methodology
Ze þ Z22 faþ ÀZ21 Ze þ Z22
Ze þ Z22
Testing and validation of results
Findings
Conclusions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.