Precision Guided Munitions (PGMs), and other so-called “smart” weapons, have established themselves as a key military technology against targets whose destruction requires a high degree of precision.
PGMs may include Bomb or missile that can be aimed and directed against a single/multi targets, relying on external guidance or its own guidance system. They can be launched from aircraft, ships, submarines, and land vehicles, or even by individual soldiers on the ground. They have high probability of hitting a target depending on timely and accurate intelligence.
PGMs provide enhanced lethality and efficiency to military against point targets by their ability to destroy any selected target at will with minimum collateral damage to both attacker and defender. Their stand-off engagement capability has given rise to the concept of “empty battlefield.” They have enhanced military effectiveness from “multiple-sorties-per-target” to “multiple-targets-per-sortie.”
Precision strikes depend on accurate navigation throughout the entire course of a missile’s flight. GPS is a key enabling technology for existing and future military precision navigation applications. Modern high performance PGMs typically employs multiple technologies to improve their robustness and accuracy. GPS provide autonomous, all Weather capabilities however is vulnerable to countermeasures.
DARPA launched SECTR program seeking to design and demonstrate a low size, weight, power, and cost (SWaP-C) seeker prototype capable of providing day/night navigation and precision terminal homing to a weapon platform which may engage moving, relocatable and stationary targets in a contested environment where GPS may not be reliably available.
The SECTR seeker will be for use in a heavily contested environment, where laser target designation is unavailable and where continuous intelligence, surveillance, and reconnaissance (ISR) support to the kill chain may not be available, DARPA officials explain.
The DARPA SECTR program is important because critical gaps exist in U.S. military capability to target and destroy moving, relocatable, and stationary targets under GPS-jammed conditions using low-SWaP-C seekers that can operate during day and night conditions, DARPA officials say. Moving and relocatable targets in particular pose continual strategic and tactical threats to the U.S. military and the U.S. homeland.
The INS has one obvious advantage over GPS – it does not require external signals, and hence, is more resistant to jamming. On the other hand, INS accuracy degrades over time due to the cumulative errors of the inertial sensors.
Active Radar/MMW Radar (Millimeter Wave) provides autonomous, engagement of selective moving targets, and all weather capability. Semi-active laser homing provides very high precision, however is vulnerable to weather & countermeasures.
Optical technologies like Scene Matching (EO) electro-optical imaging use Image-enhancing algorithms for Autonomous scene-matching guidance. Active optical technology like LADAR (Light Direction & Ranging) provides flexible targeting, and Autonomous selective targeting.
An optical seeker subsystem detects an illuminated target and supplies signals to a processor. The processor develops steering commands sent to a flight control subsystem having a plurality of guidance canards which are actuated by drive motors through gear assemblies
DARPA’s Seeker Cost Transformation (SECTR)
The Seeker Cost Transformation (SECTR) program seeks to develop novel weapon terminal sensing and guidance technologies and systems for air-launched, air-delivered weapons. SECTR technologies would enable weapons to acquire fixed and moving targets with only minimal external support; achieve high navigation accuracy in a GPS-denied environment; and be low size, weight, and cost.
The program aims to develop technologies and systems applicable to a wide range of weapons and missions, such as small unit operations, suppression of enemy air defenses, precision strike, and time-sensitive targets. The technical approach for the sensing and processing hardware will embrace both passive electro-optical infrared (EO/IR) sensors, which have evolved into very small and inexpensive devices in the commercial market, and a reconfigurable processing architecture.
In addition, the SECTR seeker will have terminal accuracy as good as, or better than, current seekers, DARPA officials say. The seeker will provide high-resolution imaging and range information for target recognition and optimum aim point selection, which will minimize the size and mass of kinetic warhead needed to destroy the target.
The SECTR seeker will included sensor for GPS-free navigation and for target and aimpoint recognition; inertial measurement unit (IMU); GPS receiver; processor; mechanical and electrical systems for power and cooling; and interfaces to weapon guidance and communication systems.
The program also seeks to develop a government-owned open architecture for the seeker with standardized interfaces between components (both hardware and software). Technologies developed under this program would transition to the military Services.
In 2015, Officials of the U.S. Air Force Research Laboratory Munitions Directorate at Eglin Air Force Base, Fla., announced an $8.2 million contract to the Lockheed Martin Missiles and Fire Control segment in Orlando, Fla., for this experimental seeker work.
BAE Systems demonstrated a new, cost-effective optical seeker for precision-guided munitions
The U.S. Defense Advanced Research Projects Agency (DARPA), through the U.S. Air Force Research Laboratory, has awarded BAE Systems a $13.1 million contract to demonstrate a new, cost-effective optical seeker for precision-guided munitions. The seeker is designed to improve navigation, as well as automate target location and homing, for different types of munitions that are used in GPS-denied and other contested environments.
BAE Systems tested the seeker during the first phase of DARPA’s Seeker Cost Transformation (SECTR) program. The SECTR seeker integrates with a wide range of weapon platforms that use munitions and can operate in day or night. It enables autonomous precision guidance via passive electro-optical and infrared sensors in environments where GPS navigation is unavailable or unreliable.
“Low-cost, precision munitions are critical to our customers, which is why we’ve developed a flexible seeker that radically lowers the cost typically associated with precision guidance,” said Mark Meisner, a chief scientist at BAE Systems. “The SECTR program is allowing us to deliver advanced sensing and navigation capabilities for munitions to warfighters faster.”
The seeker’s open architecture enables highly accurate, competitive, low-cost munitions to be capable of navigating and locating targets in limited-access and denied environments. It provides these munitions with quick-reaction capabilities while meeting stringent cost, size, weight, and power requirements. The open architecture also enables rapid seeker integration into current and new weapon systems.
This phase of the program will conclude in July 2019 with multiple test firings on several precision-guided munition platforms.