A Software-Independent Verification Interface for Flight-Equivalent Reusable IR Seeker Cooling

Abstract

To reduce the development cost and hardware consumption associated with repeated captive flight tests (CFTs), reusable infrared (IR) seeker cooling systems have been widely adopted in place of one-shot pyrotechnic cooling devices. To ensure flight-equivalent verification, the reusable cooling system must preserve the certified guidance control unit (GCU) software, ignition sequence, and operational timing of the original pyrotechnic cooling system. Conventional verification methods typically replace one-shot pyrotechnic initiators with reusable solenoid valves; however, continuous valve actuation generally requires modification of the GCU software, increasing software recertification effort and preventing flight-equivalent verification under the certified operational configuration. This letter presents a software-independent verification interface architecture that enables reusable IR seeker cooling without modification to the GCU software. The proposed architecture detects the original pyrotechnic ignition signal through a detection stage and differential sensing stage and autonomously converts the transient ignition pulse into a sustained solenoid drive signal using an SCR-based trigger stage, thereby reproducing the original pyrotechnic cooling sequence while preserving the certified operational environment. Experimental results demonstrate a hardware activation delay of approximately 12 μs, successful electromagnetic compatibility evaluation in accordance with mandatory airworthiness certification requirements, and reliable cooling verification using an operational IR seeker. The proposed interface was further validated through more than twenty ground verification procedures performed in support of more than five CFTs, demonstrating its operational reliability and practical applicability. The proposed software-independent verification architecture provides an effective solution for reusable cooling verification while preserving the certified operational configuration of the IR seeker system.