Large deployable structures are a critical part of a number of space structures and systems, such as large reflectors, Earth observation antennas, radiators, sun shields and solar arrays.
The main objective of DEPLOYTECH is to advance the technology readiness level (TRL) of three space deployable technologies by qualifying their concepts and technologies for space use. The project also aims to contribute to the broader goal of supplying Europe with space critical technologies in alignment with European strategic challenges and TRL requirements.
DEPLOYTECH has eight European partner institutions, and is assisted by NASA Marshall Space Flight Center (as an external consulting partner). The project is funded by the European Commission through the Seventh Framework Programme (FP7), and will run for three years from 2012 to the end of 2014.
Figure 1. The Inflatesail concept.
The goal of the DEPLOYTECH project is to develop three specific, useful, robust and innovative large space deployable technologies:
- an inflatable drag sail called InflateSail
- a deployable solar array of dimensions 1m x 5m
- solar sail booms of maximum length 14m
The first concept/technology proposed consists of a deployment system for a large drag sail based on a gas generator system, and ultra thin inflatable booms for structural support. Inflatesail will be built to fit in a 3 unit (3U) CubeSat (satellite platform/nanosatellite) when stowed. The standard 3U structure size is 10x10x34 cm.
The second concept/technology to be flight qualified in DEPLOYTECH involves the use of Bi-stable Reeled Composite (BRC) booms to deploy a 1m x 5m solar panel/array.
The third technology that will be flight qualified in DEPLOYTECH is a type of deployable Solar Sail Boom designed by DLR. It is made of carbon fibre reinforced plastic (CFRP), and consists of two co-bonded half shells to give a closed cross section. This same style of boom is also under consideration for DLR's Gossamer solar sailing missions.
The aim is to develop each of the technologies mentioned above from a current TRL of 2-3 to 6-8 within the 3 years of the proposed DEPLOYTECH project. An underlying support activity that will take place as part of the DEPLOYTECH project is the modelling of deployable structures with specific focus on the three mentioned concepts.
Figure 2. DLR's deployable CFRP boom (left) and boom deployment mechanism (right).
The main concern of DEPLOYTECH is to increase the TRL’s of the three deployable space structure concepts in order to address the need for greater competence in manufacturing and testing capabilities in Europe.
The three concepts involved in DEPLOYTECH are further developments of existing technologies, rather than technologies that have to be developed from scratch. The effort needed to raise the TRL of deployable CFRP booms, inflatable structures and deployable solar arrays is achievable and realistic. The applicability of these concepts is also in line with the current demand for space deployable structures and each concept fulfils an existing and growing need.
The availability of upcoming flight opportunities adds an exciting dimension to the project. In order to raise the TRL's to its maximum level, demonstration of operation in space is a necessity. The timing of these concepts and the targeted flight opportunities are ideal to achieve this.
Figure 3. Rolled-up and deployed solar panel.