CLEANSPACE. Space debris removal by ground based laser Main conclusions

Transcription

1 CLEANSPACE Space debris removal by ground based laser Main conclusions H. Haag (1) / J.E. Montagne (2) / B. Esmiller (1) / C. Jacquelard (2) / H.A. Eckel (3) / E. Wnuck (4) (1) Airbus DS (2) CILAS (3) DLR (4) AMU reproduced or disclosed to third parties, without the prior written consent from the CLEANSPACE parties owning the right to the information 1

2 Contents Project description Architecture and CONOPS of a LDR system Architecture and performances of a LDR station Focus on the laser source Roadmaps Conclusion 2

3 The Debris mitigation approaches PREVENT Guidelines to minimize post mission orbital time SURVIVE Reduce vulnerability for Debris < 5cm Reducing the Vulnerability of Space Systems to small debris collisions by shielding AVOID For known Debris >10cm REMOVE Remove Debris LARGE & SMALL Active large debris removal Net / Harpoon / Vision Space and Surveillance Tracking network Small debris removal 3

4 One possible way: small debris removal by ground-based laser ablation Laser matter interaction Laser peak power induces ablation Action & reaction of the ablated material create modification of the debris momentum This modified momentum pushes the debris Trajectory is modified 4

5 One possible way: small debris removal by ground-based laser ablation 5

6 CLEANSPACE objectives Long term objective (beyond the project) To develop a new ground based laser solution that will address small debris in LEO (from 1 cm to a few dozens of cm) in order to protect space assets from a lethal collision Project Objectives To propose an efficient and affordable global system architecture To tackle safety regulation aspects, political implications and future collaborations To develop affordable technological bricks and to establish roadmap for the development and the future implantation of a fully functional laser protection system. Technical Innovations are mainly focused on laser technologies High energy pulsed laser Scalable laser architecture Cost affordable laser technologies : ceramics, laser coherent coupling, laser pumping, 6

7 Key elements FP7-SPACE Capability Project on the topic Security of space assets from onorbit collision Selected by Research Executive Agency in 2010 Start : June 2011 Duration : 3 years Orbital debris issues Operational Concept & Laser system architecture Future utilization of laser system Laser Technologies feasibility Accompanying technologies studies Estimated performances of future system Roadmap for Laser system realization and exploitation June 2011 June 2012 June 2013 June

8 CLEANSPACE partnership Participant organisation name Participant type Project activities Country CILAS Industry Laser manufacturer France DLR (Space Agency & ITP) Airbus Defence and Space UCB Lyon LPCML Université de Limoges XLIM & SPCTS ASTRIPOLSKA Poznan Observatories Research institute laser research institute Industry Research institute Research institute Industry Research institute Space industry: System integrator Space assets protection, Space Situational Awarness Laser technologies research: ceramic for laser Laser technologies research: laser coupling and ceramic Technologies for space applications : optical devices Space Research Centre Orbitography and space surveillance assets (telescope, SLR, ) Germany France France France Poland Poland Institute of Low Temperature and structure Research Polish Academy of Sciences Research institute Laser technologies research : low cost pumping system Poland University Rovira i Virgili FICMA (Physics and Crystallography of Materials) Research institute Thermal and optical characterization of laser materials Spain 8

9 Architecture of a LDR system 9

10 Operational concept Space Situational Awareness Survey Passive & active tracking RADAR Alert Maneuvering satellite Network management LDR Engagement strategy Debris trajectography 1 m precision Laser Debris Removal engagement Schedule Catalog Identification Characterization Collision risk Debris trajectography 100 m precision Orbit cleaning Space Traffic Management Decision to de-orbit Orbit refinement Fine tracking (network) LDR strategy Debris traj 10 m precision Mobilization of the 1 st station Ultra-fine tracking Safety validation Laser illumination Post laser treatment control Elevation > 2 Elevation > 15 Elevation > 100 Mobilization of the i+1 station End of strategy Re-entry predictions Continue strategy Re-entry 10

11 Laser operations : ISDRO International Space Debris Removal Organisation (ISDRO) for operation under United Nation should be put in place. ISDRO will develop an operational strategy for international control and information strategies based on corresponding capabilities and functions: To decide which debris to deorbit To assume the full responsibility and liability of these actions To exchange data with Space Operation Commands and Accountable LDR operator To give possible veto on engagement based on study of the engagement plan 11

12 Architecture of a LDR station Beam generation Laser source : power supply, master resonator, power amplifier, thermal management, etc. Beam shaping : auto-alignment, phase control, beam sampling, etc. Beam pointing Telescope : mirrors, two-axis gimbal, active optics, etc. auto-alignment and fine tracking : internal tilt control elements Compensation of atmospheric turbulences (adaptive optics) : LGS, DM and WFA Software and automation Safety function Area 3 Space traffic management (laser cone) Area 2 Air traffic management (radar) Area 1 Proximity protection (camera) 12

13 Estimation of performances Modelling the v as a function of: The energy [J] collected by the object : function of the characteristics of the LDR station (energy of the laser source, diameter of the telescope, performance of the adaptive optics system, etc ), the atmospheric properties, the distance and the surface of the target The mass [kg] of the object The coupling coefficient [N.s/J] function of the material of the object, the wavelength and the intensity of the laser beam 13

14 Coupling coefficient Modelling the coupling coefficient, taking into account the vapor and the plasma regime [1] the laser intensity (W/m²) the pulse duration (s) the wavelength of the laser (m) the material the shape of the object Experimental validation (vacuum) on representative space materials [1] C. Phipps «An Alternate Treatment of the Vapor-Plasma Transition» International Journal of Aerospace Innovations Vol 3 N 1 (2011) 14

15 Fluence on debris Modelling of the energy collected by the debris as a function of the laser source (energy, pulse width, repetition rate, jitter, beam quality) the telescope (optical architecture, diameter) the atmosphere (transmission, performance of the adaptive optics system) the location of the LDR station (altitude, longitude, latitude) the orbital parameters of the debris (altitude, eccentricity, inclination, area to mass) Expression of v as a function of time + Short-term orbit propagator on real orbits Perigee lowering & desorbitation time 15

16 Influence of parameters (vs state of the art) Influence of the repetition rate Influence of the diameter of the telescope Influence of the firing strategy 16

17 The targeted configuration (1/2) Station Night and day operational capabilities Located far away from airports (70 km), air routes (50 km) and inhabited areas (7,5 km) Laser Wavelength : between 1 and 1.1 µm Pulse width : 1 to 10 ns Energy : 10 to 50 kj/pulse Repetition rate : > 10 Hz Beam quality : M²~3 Beam pointing stability : 70 nrad Telescope Diameter : 4 to 6 m Total tracking accuracy : 100 nrad Performances of the AO system : Strehl ratio > 80% 17

18 Perigee altitude [km] The targeted configuration (2/2) For a typical debris (S/M = 0,2), the expected perigee lowering is about 30 km for a single pass at 800 km Complete desorbitation of a typical debris within a few dozen days Possibility to modify the orbit of large objects (S/M < 0,05) Station No 7 - Kourou, Object No a = 7013 km, e = , I = 73.9, pg = 520 km laser en. 25 kj, tel. diam. 4m, repet. rate 10 Hz sm=1 sm=0.05 sm=0.3 sm=0.1 sm=0.05 sm= time [days] T 0 = Perigee lowering as a function of time Multi-pass removal strategy Perigee lowering as a function of time for different S/M ratio 18

19 Laser requirements Need for high energy laser: >10kJ/pulse Need for high repetition rate: ~50Hz Need for high peak power : ns class Need for high fluence on debris Need for high beam quality : M²~3 Very challenging laser design (1 line of LMJ or 50 Hz) Very large aperture gain elements Limited thermal management properties Solution: a large number of combined individual lasers 19

20 Laser technological feasibility Initially two architectures were studied Active coupled thin disk (Yb:Yag) with MOPA architecture Passive coupled Q-switch Néodyme doped lasers Without Laser coherent coupling A third architecture was selected A typically 10 joules/arm x 1000 arms architecture (1064 nm) Active coupling Near field Unphased beams Far field More scalable laser architecture The initial brick could also be the brick for SLR need Affordable laser pumping With Laser coherent coupling Phased beams Classical semi-conductor and new Vertical Emitting Cavity Semiconductor lasers (VCSEL s) are surveyed (cost driver) 100 $/J=> 8 M$ for laser diodes?? ( ~ 80 M$ on actual energy/array) 20

21 Choice=10J Choosing the right laser building block Criteria Total cost (development + production) Same laser block needed by other applications Schedule-effective Higher number of elements Higher complexity Industrial applications Scientific applications 21

22 10 J laser Brick - Technology Room temperature Multi-mini-heads Direct pumping Thermal, mechanical and optical model 200 mj demonstrated Space compatible technology 22

23 9 beams demonstrator architecture Narrow linewidth 1064nm 15ns 90mJ M²=1.5 Nd/YAG QS oscillator Narrow linewidth CW 1030nm laser diode 1064/1030 multiplexer Phase modulator Beam Splitter 1 9 P Beam matrix stretcher + delay line Li<100µm Double pass amplifier Double pass amplifier Double pass amplifier Reference beam expanded Dichroïc mirror Beam analyser Energy measurement Interferometer filter PhD matrix Lock in amplifier Piezzo Actuators matrix 23 23

24 Pictures of the laser setup Piezzo actuators Amplifiers Master oscillator 24

25 Coherent coupling experiment 25

26 Laser brick development Laser Roadmap Strategy through high energy laser or laser shock peening (for material hardening) Technology demonstrator Development of 400 mj breadboard: Aladin and spatialization capability 10 J amplifier as building brick for coherent coupling or space application Next step to be defined depending on strategy (ground / space based) mJ technology demonstrator 400mJ Amplifier dvpt 10J amplifier dvpt Space application Coherent coupling and ground application 26

27 CLEANSPACE Roadmap 27

28 Conclusion Feasibility confirmed Architecture, operational concept and high level requirements of a LDR system Realistic performances of a LDR station (laser, telescope, AO, location, orbit) Validated architecture of a scalable laser source Demonstration of a pushing effect under vacuum, by using 9 coherently coupled laser lines 10 years roadmap for a future LDR system An international collaboration is required 28 28