SBIR-STTR Award

A major challenge facing the U.S. Navys Anti-Submarine Warfare (ASW) mission area is the ability to effectively detect, classify, localize and neutralize quiet modern submarines in shallow water. To address this challenge requires deployment of distributed network centric sensor systems that provide the search rate needed to leverage the full complement of US Navy war fighting capability. Unmanned Surface Vessels (USV) and Unmanned Underwater Vehicles (UUV) outfitted with compact towed array sensors have the potential to deliver the transformational capability needed to meet operational objectives in the littorals. Current towed array sensors, including TB-23, TB-29A, TB-16 and MFTA, provide desired acoustic performance but are not optimal for deployment from an unmanned vehicle. Compatibility with these platforms requires significant reductions in sensor power, diameter, bend radius and production cost. Maintaining performance comparable to existing Navy tactical towed arrays requires reduced susceptibility to mechanical/vibrational noise and incorporation of directional sensors for left-right contact resolution. Development of next generation reliable compact towed arrays that can be stowed and deployed from unmanned vehicles, surface ships and submarines supports the Sea Shield Pillar of Sea Power 21 while achieving substantial fleet life cycle cost savings.

Benefit:
Successful implementation of the Compact Towed Array SBIR provides the Navy with major technological advancements in towed array capabilities. Our approach proposes to develop a common ultra-thinline towed array for use across a broad range of unmanned platforms (USV/UUV/UUG). The use of directional vector sensors provides significant performance advantages including instantaneous left/right ambiguity resolution, ability to null own ship noise, immunity to multi-path signal fading, and improved sensor DI which allows for shorter arrays with equivalent performance to longer arrays.

Keywords:
TAIPT, TAIPT, ultra thinline towed array, USV/UUV towed array, Handling System, Vector sensors, Telemetry

A major challenge facing the U.S. Navy’s Anti -Submarine Warfare (ASW) mission area is the ability to effectively detect, classify, localize and neutralize quiet modern submarines in shallow water. Current towed array sensors, including TB-23, TB-29A, TB-16 and MFTA, provide desired acoustic performance but are not optimal for deployment from an unmanned vehicle. Compatibility with these platforms requires significant reductions in sensor power, diameter, bend radius and production cost. The Compact Towed Array (CTA) SBIR Phase II effort will result in development of high-performance towed array components that provide multi-mission, directional sensing capabilities for submarine, surveillance, surface ship and unmanned vehicle towed arrays. All of the potential applications for CTA technology benefit because the superior performance acoustic sensors and electronics are small enough to provide a ubiquitous solution across the spectrum of fatline, thinline and ultra-thinline arrays. Multi-mission commonality is a primary goal for these high volume components that will provide cost savings throughout the entire supply chain starting with procurement and extending through life-cycle support. Development of next generation reliable compact towed arrays that can be stowed and deployed from multiple platforms supports the Sea Shield Pillar of Sea Power 21 while achieving substantial fleet life cycle cost savings.

Benefit:
The Compact Towed Array (CTA) SBIR effort will result in development of high-performance towed array components that provide multi-mission, directional sensing capabilities for submarine, surveillance, surface ship and unmanned vehicle towed arrays. All of the potential applications for CTA technology benefit because the superior performance acoustic sensors and electronics are small enough to provide a ubiquitous solution across the spectrum of fatline, thinline and ultra-thinline arrays. Multi-mission commonality is a primary goal for these high volume components that will provide cost savings throughout the entire supply chain starting with procurement and extending through life-cycle support. Directional sensing represents the next major technical breakthrough for towed array sonars. Instantaneous left-right resolution against submarine or torpedo threats have the capability to provide our forces with an acoustic advantage and sufficient time necessary to launch an anti-torpedo torpedo (ATT) in a self-defense situation. Although cardioid hydrophone arrays have proven effective for resolving bearing ambiguity, the size of the array, typically 3.5 to 4-inch diameter, presents handling and stowage limitations especially when one considers smaller unmanned platforms. Vector sensors and supporting electronics using CTA technology allow towed arrays as small as 0.75-inch with better overall system performance. In addition to the obvious military applications we have also identified opportunities to transition CTA technology to the off-shore seismic exploration community. Currently, seismic streamers are towed at shallow depths ranging between 15-feet and 30-feet below the surface to minimize the impact of "Lloyd’s mirror" due to reflections caused by the air/sea interface. Streamer operations are ineffective once the sea state and wave height cause array broaching the surface. Directional sensors have the ability to null the surface reflection thus allowing streamers to be towed deeper and provide a much larger weather window over which to operate. The off-shore geophysical exploration business is continuing to grow as a result of increased demand and record setting oil and gas prices. The high-end (3-D) exploration market uses a fleet of specially designed platforms that have the ability to tow as many as twenty streamers at one time. Each streamer is typically 8-km long and contains about 960-channels. Each channel is generally comprised of eight hydrophones. That equates to approximately 20,000 electronic channels and over 150,000 hydrophones per ship. Using vector sensors increases the number of channels by a factor of four to 80,000 and instead of single hydrophone elements each sensor would have four outputs (three accelerometers and one hydrophone). A dual use market of this size would dramatically improve economies of scale and cost effectiveness for government applications. KeywordsUSV, ATAT Construction, UUG, UUV, Telemetry, Towed arrays, Directional sensors