Deployable Gossamer Sail for Deorbiting

Objectives

The purpose of this project is to develop a gossamer sail system that can be used for deorbiting satellites at end-of-life. The principle that the system will use to achieve deorbiting is aerodynamic drag from the larger surface area. The system is intended mainly for low Earth orbits (LEO) but can potentially also be used in higher orbits, making use of solar radiation pressure to perform end-of-life manoeuvres. The objectives for the project are:

• Undertake a detailed analysis of the requirements and potential use cases of a deployable sail deorbiting system.
• Compare the concept with current de-orbit strategies and technologies.
• Design, manufacture and test an engineering model gossamer sail deployment system

Features

The deorbiting system will feature a two-stage deployment process. The first deployment will use a telescopic mast to extend the sail deployment mechanism so that it will not interfere with other satellite appendages and protrusions. The deployer is based on the commonly-used poly-picosatellite orbital deployer (P-POD) system used for standard cubesats. It will consist of a series of box-like structures that will deploy telescopically from the main body using rails.

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In the next deployment phase the sail itself will deploy. The sail consists of 4 triangular sections supported by 4 booms. The booms are coiled around a centre hub and the sail is folded in a separate volume. Deployment of the sail is due to stored energy in the coiled booms.

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Project Plan

The initial analysis and technology survey will take place in the first month of the project with a review scheduled in the beginning of October 2011. The system requirements will be established by the beginning of December and a design review will take place in the beginning of February 2012 after which an engineering model will be constructed. Functional and environmental testing will take place from March to May 2012. The final review meeting is scheduled for beginning of June 2012.

Challenges

This project will address the growing concern of orbital debris. The gossamer deorbiting system that will be designed in this project will provide manufacturers of future space equipment with a means to de-orbit the equipment in compliance with the European Code of Conduct for Space Debris Mitigation.

Benefits

The proposed de-orbiting system has advantages above other alternatives. It does not require propellant or electrical power throughout the de-orbiting phase and it is generally less complex than systems based on chemical or electrical propulsion. The system will be designed for an optimal de-orbiting strategy and low parasitic mass. The technology readiness level of solar sail and deployable sails is also at a high enough level, making this concept more feasible than other experimental technologies.

Current Status (dated: 13 Sep 2011)

The team is currently establishing needs and use cases of the system, performing analysis and determining the high-level requirements. We are also making a survey of existing and proposed de-orbiting strategies for comparison purposes.