Development of an Arm-Fire Device with Enhanced Fail-Safe Mechanism for Rocket Motors

Joo Young Jin; Seung-gyo Jang

doi:10.6108/KSPE.2025.29.6.001

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2025 Vol.29, Issue 6 Next Page

RESEARCH PAPERS

Development of an Arm-Fire Device with Enhanced Fail-Safe Mechanism for Rocket Motors Fail-Safe 기능이 강화된 로켓 모터용 점화안전장치 개발

31 December 2025. pp. 1-6

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Abstract

This study proposes an electronic-mechanical arm fire device (EMAFD) with enhanced fail-safe mechanism using the arming confirmation sensor that applies a Hall sensor. By activating the sensor as the torque motor is fully rotated, the accuracy of detecting the arming state has been improved. Additionally, the operational temperature range has been expanded from -25°C to –45°C. The device's reliability was validated through testing 108 samples to verify the arming confirmation sensor, arming time and return time. Testing 32 samples across temperatures verified stable operation within -45°C to +75°C. Based on the U.S. military standard, low-temperature, high-temperature, and altitude tests were conducted on four samples, confirming that variations in arming and return times before and after testing were within 10%. Ignition performance was verified through a CBT test of four samples in high (+65℃) and low (-45℃) temperatures, and these results indicate that the proposed EMAFD is suitable for military weapon systems

Keywords

Arm Fire Device

Solid Rocket Motor

Hall Sensor

Closed Bomb Test

Environmental Test

본 연구에서는 홀센서를 적용한 장전확인센서를 사용하여 Fail-Safe 기능이 강화된 전자기계식 점화안전장치를 제안한다. 토크모터가 완전히 회전한 상태에서 센서가 작동되도록 하여 장전상태 감지 정밀도를 높였으며, 저온 운용 범위를 기존 광센서의 –25℃에서 –45℃로 확대하였다. 108개의 제작된 장치로 장전확인센서 작동과 장전시간, 복귀시간을 확인하여 설계의 신뢰성을 검증하였다. 32개 장치에 대해 온도별 CBT시험을 통해 –45℃~+75℃에서 정상 작동하는 것을 확인하였다. 미국 국방규격에 따른 저온, 고온, 고고도 시험을 4개 장치를 사용하여 수행하였으며 시험 전/후 장전시간과 복귀시간의 변화가 10% 이내임을 확인하였다. 4개 장치에 대해 고온(+65℃)과 저온(–40℃)에서 CBT 시험을 통해 정상 작동을 확인하였으며, 제안하는 점화안전장치가 군사 무기체계에 적용가능함을 나타낸다.

키워드

점화 안전장치

고체추진기관

홀센서

밀폐용기 시험

환경시험

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Information

Publisher :The Korean Society of Propulsion Engineers
Publisher(Ko) :한국추진공학회
Journal Title :Journal of the Korean Society of Propulsion Engineers
Journal Title(Ko) :한국추진공학회지
Volume : 29
No :6
Pages :1-6
Received Date : 2024-12-16
Revised Date : 2025-07-24
Accepted Date : 2025-08-21
DOI :https://doi.org/10.6108/KSPE.2025.29.6.001

Journal of the Korean Society of Propulsion Engineers ISSN:1226-6027(Print) 2288-4548(Online) 한국추진공학회지

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