PAGE CONTENTS
Objectives
The objectives of the CITRUS project are double: improve the automated manufacturing process and increase the readiness level of a new composite structural product range mainly used in Telecommunication Satellites. Three products are targeted: Hyperstable Composite Tubes for antennas and reflector arms, Composite Booms New Generation for deployable systems and One-Shot Struts for structural applications. CITRUS focusses in upgrading quality, lead-time, serialisation and performance repeatability in terms of stiffness and stability in accordance with main end-users needs.
Challenges
A key transversal challenge concerns the mastering of the automated fiber placement means whatever layups, product shapes and interfaces to make this process highly repeatable and reproducible.
Technical challenges are function of the product:
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For Hyperstable Composite Tubes, the challenge consists in finding layup adapted to both high stiffness and high stability.
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For Composite Booms New Generation, challenges are to qualify the CFRP-Titanium bonding and to develop a new concept to facilitate satellite AIT.
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For One-Shot Struts, challenges mainly concern the extractible mandrel in terms of manufacturing process and geometrical accuracy, but also the integration of coaxial metallic inserts during layup.
System Architecture
Hyperstable Composite Tubes are structural components part of:
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Reflectors backing structures,
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Deployable arms after assembled with end-fittings to compose Composite Booms New Generation as structural subassembly.
One-Shot Struts are structural subassemblies part of secondary structures or antenna feed support structures.
Plan
The CITRUS project is divided in 3 phases for the 3 products:
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A definition phase for definition of specifications,
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A technology phase to de-risk the critical materials and processes,
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A product phase to manufacture and qualify first models.
Inside these phases, milestones concerning validation of designs, materials, processes and tests are foreseen.
Current Status
The 3 developed products have 3 different levels of maturity and advancement in the project:
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The development of Hyperstable Composite Tubes has already been performed since these tubes are involved in a current project with first delivery milestones during the CITRUS project. First deliveries have been successful.
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Works on technological blocks are under progress for the One-Shot Struts products, mainly lay-up optimization for mechanical properties and external aspect.
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The use of tubes manufactured with Automated Fiber Placement (AFP) for Composite Booms New Generation has been qualified. The feasibility to improve their design for facilitating AIT is under progress. Concepts are going to be studied for a first validation by mechanical analyses.
