Opto-pyrotechnic initiation for the SHarK system of the French MOD

Transcription

1 November 18,2008, CNES Opto-pyrotechnic initiation for the SHarK system of the French MOD

2 Contents 1-Operational requirements of the initiation device for SHarK 2-Candidate Technologies 3-Choice of the Laser initiation components 4-Demonstrator SHarK1 5-Evolution for the SHarK2 demonstrator 1

3 Active Protection System Detection Identification Firing Decision Distributed sensors Distributed counter-measures Confirmation Tracking Interception Distance / Time Reaction time < 0,1 second Sensors Calculator Counter measures 2

4 Operational requirements for the initiation device Initiation of the counter measure Short dispersion on the functioning time of the detonator Integration constraints (volume, environments) Compliance with safety standards and fuzing rules Short arming delay (<10ms) for safety concern Resistance to electrostatic and electromagnetic radiations 3

5 Candidate Technologies (1) Stanag 4187 describes two types of fuzing systems: interrupted or non-interrupted explosive train Interrupted explosive train When the explosive train contains primary energetic substances, the train is to be interrupted with a mechanical barrier in order to isolate the primary explosive from relays. Non interrupted explosive train Explosive train interruption is not required when only allowed energetic substances are used in the train (Stanag 4170). 4

6 Candidate Technologies (2) Non-interrupted explosive train (1/2) Electronic SAD with slapper detonator: Requires to place the energetic HT electrical source close to the detonator to insure the conditions of plasma formation. This implies a consumable device with associated cost. ASTER 5

7 Optical initiation device : A laser source is used to initiate an energetic substance This innovative technology: Is compliant with the requirements Has capacity for multipoint initiation Allows architecture flexibility Candidate Technologies (3) Non-interrupted explosive train (2/2) Is supported by feasibility studies performed on 2 types of optical detonators DOP by ISL/CNES and on the IODEP by TDA/CEA This technology was given full consideration although the development remained to be performed 6

8 Laser initiation components (1) A system analysis was performed in order to determine the best suitable components of the laser initiation device Optical detonator Laser source Fibre optics with their connectors 7

9 Laser initiation components (2) Shock Initiation Thermal Initiation Detonator IODEP (TDA/CEA) DOP 2 stages (DOP2 from ISL) DOP 1 or 2 stages (DOP1 ISL) Laser power density GW/cm² MW/cm² kw/cm² Laser source characteristics Solid State Laser Q-Switch mode Solid State Laser Free-running mode Diode laser Response time of the detonator 1,2 μs 50 μs 200 μs 1 ms Dispersion over the response time Energetic substances ± 100 ns Secondary (HNS) STANAG 4187 ±5 μs Secondary (HMX/CB) STANAG 4187 ± 20 à 100 μs Secondary (HMX/CB) 8

10 Laser initiation components (2) Shock Initiation Thermal Initiation Detonator IODEP (TDA/CEA) DOP 2 stages (DOP2 from ISL) DOP 1 or 2 stages (DOP1 ISL) Laser power density GW/cm² MW/cm² kw/cm² Laser source characteristics Solid State Laser Q-Switch mode Solid State Laser Free-running mode Diode laser Response time of the detonator 1,2 μs 50 μs 200 μs 1 ms Dispersion over the response time Energetic substances ± 100 ns Secondary (HNS) STANAG 4187 ±5 μs Secondary (HMX/CB) STANAG 4187 ± 20 à 100 μs Secondary (HMX/CB) The ISL DOP2 along with a solid-state laser source in a free-running mode comply with the requirements 9

11 Laser initiation components (3) Flash-pumped solid-state laser sources in free-running mode are well-suited to the energetic need of the DOP2 to reach targeted dispersion values. Robust, miniaturised, high-power Nd:YAG laser sources with high resistance to harsh environments have been developed in collaboration with Institut Carnot de Bourgogne. V HT Capacitor Trigger + Mirror M2 Flash Lamp Laser rod Mirror M1 Laser beam 10

12 Demonstrator SHarK1 A first demonstrator SHarK1 (2005) implemented a 1 st generation of Laser Initiation Unit (LIU). 120 firings of LIU were performed successfully. This demonstrated a 1 st level of feasibility of the opto-pyrotechnical device for SHarK. 11

13 Tension 24V vehicle Architecture of 2 nd generation LIU LIU SHarK2 DC/DC converter HT Capacitor Triggers Flash 1 Laser 1 Flash 2 Laser 2 Laser Initiation Unit DOP 1 DOP 2 Flash n Laser n DOP n Power supply Laser sources Optical fibres & connectors Detonators Countermeasures 12

14 Laser source SHarK2 -High power laser source 3,5 kw -Compactness and ruggedness improved -No mechanical adjustment of the laser fibre coupling -Temperature testing succeeded in the range 35 C to +70 C Electrical connector Laser cavity Optical connector with laser injection device Flash lamp Optical cavity & electronic boards Optical fibre 13

15 Power supply SHarK2 This specific power supply is a 2 stage capacitors : -1 st stage capacitor -2 nd stage capacitor having: - rapid electric charge time <10 ms (after trigger from calculator) - rapid electric discharge time into the laser flash (idem) Successfully passed electromagnetic and vibration tests 14

16 LIU SHarK2 A specific LIU was developed with: -3 electronic cardboards: HT supply, flash triggering, calculator link -36 laser sources Optical connectors LASER Sources Electronic cardboards 15

17 LIU integration in VAB Optical lines are running along the sides of the vehicle and address the detonators within the CM Optical lines Power supplies Laser Initiation Units 16

18 17 LIU LIU SHarK2 video

19 Summary A Laser Initiation Unit has been developed with regards to the Shark requirements An optical detonator DOP (ISL/CNES) A solid-state flash pumped laser source Nd:YAG (TDA/ICB) A power supply (TDA) It has been tested successfully for the SHarK demonstrators (SHarK2 under tests) A 3 rd generation LIU will be developed in future contracts (miniaturisation and environments) 18

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