Invariant Corporation has integrated the FireFLY passive acoustic sensor and its artificial intelligence-driven EO/IR architecture with the Surface to Air Kinetic Engagement (STAKE) counter-uncrewed aircraft system (C-UAS), establishing a passive sensor-to-effector kill chain.
The integrated capability uses acoustic signatures generated by UAS to detect, classify and determine the location and altitude of an approaching aircraft without transmitting radar or radio-frequency energy. US defence department officials have recently highlighted the operational value of passive systems that enable forces to detect threats without revealing their positions in the electromagnetic environment.
The acoustic detection system automatically cues Invariant’s passive EO/IR sensor towards the area of interest. The onboard Drone Vision AI stack is designed to search the live video, locate the UAS within the image, fuse the data and maintain target lock as the aircraft moves through the environment, without any operator input required. The resulting track data is passed to the kinetic system’s fire control to develop a refined firing solution.
FireFLY is developed jointly by Invariant Corporation and Hyperion Technology Group located in Tupelo, Mississippi. The system is designed to complement, not replace, radar, electro-optical/infrared, and radio-frequency sensors, allowing commanders to construct a layered architecture appropriate to the mission, terrain, threat and available resources. FireFLY can also serve as a complementary sensor layer inside broader C-UAS architectures.
Invariant plans to continue system testing and interoperability demonstrations with US government and industry partners. Future activities are expected to focus on expanding acoustic detection coverage, integrating additional identification and tracking sensors, and connecting the architecture with government command-and-control networks.
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