ABSTRACT The Fourth International Symposium on Solar Sailing 2017 17th - 20th January, 2017, Kyoto, JAPAN

Title of Paper Survey of available boom technologies, the related TRL2 (and 3) and when will we reach our solar sails missions objectives

Corresponding Author Name Florio DALLA VEDOVA Title Mr. Affiliation LuxSpace S.à.r.l

Co-Authors Name Pierre MORIN Title Mr. Affiliation LuxSpace S.à.r.l

Abstract

Since the first attempts to develop solar sails world-wide efforts have been distributed (some could/would even say “diluted”) over several decades and over many projects. For most of the (national) Teams it is still hard to develop large sailcrafts for photonic propulsion and to forecast when they could reach their objectives in terms of TRL 8/9 for a desired sailcraft size. With the success of IKAROS in 2010 and the recent increased interest for “functional” sails (e.g. DragSails or PowerSails) chance is given now to the various Teams to progress on solar sailcrafts thanks to these new, similar (and typically smaller) sails developments.

The question of every Team is thus to understand how much these new, intermediate “functional” sails developments contribute to the final objective of building and deploying in Space large and efficient SolarSails.

The present paper aims at giving elements of answers to this question by proposing the TRLn concept. The paper is structured in three parts:

 The first part of the paper is devoted to the introduction and explanation of the proposed TRLn concept, suitable to track the technical achievements of scalable products (here for boom length and film thickness). As examples, the evolution of the TRL2 of the Japanese sails programme until and after IKAROS [1] and, the TRL3 values of the three reference missions listed in the “2004 solar sails roadmap” [2], together with IKAROS, are presented.

 The second part of the paper comes in support of the TRL2 (3) assessments and forecasts by identifying the current status (understand size limitations) of deployable and inflatable boom technologies world-wide. The presented survey of available boom technologies provides key technical figures as a function of boom type family, materials, diameter and deployed length.

 The last part of the paper presents shortly the on-going developments of the various (functional) Sails “Made in Luxembourg” with the four running projects DoWn!, DGNC, ReDSHIFT and LDAS. [1] H. Yano (Presenter) et al., JAXA/ISAS, Japan: “JAXA Report on -2, Procyon, and International Collaboration Sample Return Working Group”, presented to NASA Advisory Council Planetary Protection Subcommittee 21st of May 2014

[2] M. Macdonald, C. McInnes, resp. University of Glasgow/of Strathclyde, Scotland : “A Near-Term Roadmap for Solar Sailing”, paper IAC-04-U.1.09 presented at 55th International Astronautical Congress 2004 - Vancouver, Canada

[3] R. M. Young, Ch. L. Adams, NASA : “TRL Assessment of Technology Development Following the 20-Meter System Ground Demonstrator Hardware Testing”, presented at 2nd International Symposium on Solar Sailing (New York, USA – 2010)