N102-181 TITLE: Acoustic Vector Projector Technology

TECHNOLOGY AREAS: Materials/Processes, Sensors, Battlespace

ACQUISITION PROGRAM: Forward Sector Torpedo Defense Enabling Capability for POM12

RESTRICTION ON PERFORMANCE BY FOREIGN CITIZENS (i.e., those holding non-U.S. Passports): This topic is "ITAR Restricted." The information and materials provided pursuant to or resulting from this topic are restricted under the International Traffic in Arms Regulations (ITAR), 22 CFR Parts 120 - 130, which control the export of defense-related material and services, including the export of sensitive technical data. Foreign Citizens may perform work under an award resulting from this topic only if they hold the "Permanent Resident Card", or are designated as "Protected Individuals" as defined by 8 U.S.C. 1324b(a)(3). If a proposal for this topic contains participation by a foreign citizen who is not in one of the above two categories, the proposal will be rejected.

OBJECTIVE: Develop, fabricate, and demonstrate a very compact high powered underwater sonar transducer array capable of directional transmissions at high duty cycle operation, very high reliability, and a low manufacturing cost.

DESCRIPTION: The performance of naval systems for Anti-Submarine Warfare (ASW) and Counter-Torpedo Detection, Classification, and Localization (CTDCL) is limited by the size, power and detection range of current sensor systems. Although current sensors are adequate for current missions, emerging missions and the need for reducing the volume and weight of sonar transducer arrays while improving reliability under high duty cycle conditions prompts the need for the development of innovative very high power, broadband, directional transmitting arrays while reducing the size and weight compared to traditional transducer arrays. The utilization of projector driver materials that can withstand heat extremes and are very durable and have low material sound velocity (to reduce the size of the transducer) will permit the design of highly compact projector arrays that can generate transmit beams that can be electrically steered.

PHASE I: Identify active driver materials which, when combined with appropriate device design, are able to produce high power, broadband, directional sound transmission at high duty cycle and pulse duration. Develop a model or metric as a means to rank potential active drive materials and innovative transduction mechanisms that can be used in this development. Assess the effects of the combination of high duty cycle and long-term reliability upon the transducer driver materials and the various electrical wires, elastomeric compounds and epoxies that would comprise the final device. Assess the impact of environmental effects on the driver materials under consideration to predict ruggedness and long-term degradation. Undertake analyses (using analytical or numerical models) to determine acoustic performance and integrate in potential long-term performance changes as a result of high duty cycle operation in a continuous manner over multiple years of in-service use. Determine the best material/device combination, analyze and identify possible shortfalls in both drive materials and device mechanisms (laying out a development path to remediate the identified shortcomings) and then perform thermal analysis to assess the need for ancillary thermal control schemes to insure reliable operation. If additional thermal dissipation is needed, integrate the components into the model used to predict service life and reliability. Construct a notional paper design for the selected concept and perform analyses to quantify performance.

PHASE II: Complete the design of the transducer and array and fabricate prototypes for validation of predicted behavior. After tests of prototype devices, fabricate a full prototype array. This work may become classified in Phase II.

PHASE III: Undertake engineering analysis of the prototype array to improve the acoustic performance and to apply cost-effective manufacturing techniques as a means to lower total system cost. Design, develop and demonstrate additional prototype arrays at-sea and on Naval vessels for specific applications. Integrate the transducer array with efficient and compact power amplifiers and demonstrate a complete transmit subsystem. The the appropriate technical and programmatic steps to effect a transition into a program of record.

PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: This technology will have a host of applications in commercial underwater imaging and fish finding applications.

REFERENCES:
1. S.C. Butler and Julie Slaughter, "Vector Projector - A Unidirectional, Magnetostrictive, Compact Sonar Transducer Design", NUWC-NPT Technical Report 11.918, Naval Undersea Warfare Center Division Newport, RI, 1 July 2009 (Unclassified)

2. C.H. Sherman and J.L. Butler, "Transducers and Arrays for Underwater Sound", Springer (2007)

3. J.L. Butler, A.L. Butler and J.A. Rice, "A tri-modal directional transducer", J. Acoust. Soc. Am. 115 (2), pp. 658-665 (February 2004)

4. S.C. Butler, "High Frequency Broadband Projector (HFBBP): Wideband Projector Design and Test Results", NUWC-NPT Technical Memo 08-061, 29 August 2008, Naval Undersea Warfare Center Division Newport, RI (Unclassified)

5. A.D. Waite, "Sonar for Practising Engineers", Wiley (2002)

6. J.L. Butler, "Modal Acoustic Array Transducer Apparatus", U.S. Patent 7,372,776 B2 (13 May 2008)

KEYWORDS: transducer; vector projector; directional beams; array; high power; reliable

** TOPIC AUTHOR (TPOC) **

DoD Notice:   Between April 21 and May 19, 2010, you may talk directly with the Topic Authors to ask technical questions about the topics. For reasons of competitive fairness, direct communication between proposers and topic authors is not allowed starting May 19, 2010, when DoD begins accepting proposals for this solicitation.

However, proposers may still submit written questions about solicitation topics through the DoD's SBIR/STTR Interactive Topic Information System (SITIS), in which the questioner and respondent remain anonymous and all questions and answers are posted electronically for general viewing until the solicitation closes. All proposers are advised to monitor SITIS (10.2 Q&A) during the solicitation period for questions and answers, and other significant information, relevant to the SBIR 10.2 topic under which they are proposing.

If you have general questions about DoD SBIR program, please contact the DoD SBIR Help Desk at (866) 724-7457 or email weblink.