Satellite design for demise thermal characterisation in early re-entry for dismantlement mechanisms

摘要

Preliminary analyses at ESA have shown that space objects in LEO with masses above 500 kg might already imply an on-ground casualty risk higher than 1E-4 in case of uncontrolled re-entry. Compliance to this casualty risk requirement may be achieved through controlled re-entry, but this solution has a major impact at system level. Sometime it requires a full re-design of the spacecraft and may involve switching to a completely different launcher performance (consequently a significant mission cost impact).This option may be avoided with achievement of compliant ablation (demise) of the spacecraft upon uncontrolled atmospheric re-entry. The so-called Design-for Demise discipline (D4D) is a highly multidisciplinary approach that can bring significant benefits in the future missions in the medium to long term. (Klinkrad, 2006; Johnson, 2012) [1,2].ESA created in 2012 the "Cleanspace" initiative and team to promote actions on green aspects and debris remediation (ESA Clean Space Team, 2015) [3]. Recently ALTRAN was involved inside THALES ALENIA Space consortium in those ESA activities on S/C D4D techniques and proposed several D4D concepts. This ESA D4D study had the objective to find D4D solutions for the Sentinel-1 study case (around 2 tons). This objective were about to be theoretically achieved. [4].The outcomes of those D4D studies performed in parallel at level of 3 LSI (Large System Integrator) were concluded in early 2016 [4,5] and used mainly ESA Sentinels S/C as study cases. Those studies all demonstrated that S/C dismantlement (controlled and earlier to natural break-up) has a major benefit in reduction of S/C Debris Casualty Area (DCA). Then this technique has to be considered with high priority in a global approach for D4D improvement. (ESA, 2015; CleanSat Workshop presentations, 2015) [6,7].The proposed ALTRAN/NIMESIS study CLEANSAT Building Block 10: Shape Memory Alloys (SMA) Dismantlement Mechanisms has investigated several technological devices and SMA material options for their suitability to be implemented in LEO satellite H/W of main European LSI for dismantlement during atmospheric re-entry.