Emerging Technologies For A Modernized Rocket Launcher

Transcription

1 Emerging Technologies For A Modernized Rocket Launcher Approved for public release; distribution unlimited. Review completed by the AMRDEC Public Affairs Office 17 Mar 2010; FN4504." DISCLAIMER: Reference herein to any specific commercial, private or public products, process, or service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its endorsement, recommendation, or favoring by the United States Government. The viewing of the presentation by the Government shall not be used as a basis of advertising.." Deborah A. Butler Launcher Electronics Technology Team U.S. Army AMRDEC ATTN: RDMR-WDP-C Redstone Arsenal, AL [email protected] Phone: FAX: Malcolm Morrison OAR Corporation 7047 Old Madison Pike NW Suite 320 Huntsville, AL [email protected] Phone: FAX: Abstract The next generation of rocket launchers must provide nonproprietary, open architecture interfaces to the platforms and munitions served while supporting future guided rockets and maintaining backwards compatibility with legacy rockets. New technology developments with guided rockets and digital fuzes cannot be fully utilized with existing M260 and M261 rocket launchers and these existing launchers cannot be retrofitted to support these developments. A new Modernized Rocket Launcher (MRL) will be backwards compatible with the family of legacy 2.75 inch rockets and will support new capabilities being designed into future guided and unguided rockets. The candidate technologies being explored for use in the MRL cover a range of maturities. Proven military solutions such as MIL-STD-1760 will be used in the platform to MRL interface. Widely used commercial technologies such as Radio Frequency Identification (RFID) show potential for weapon identification but would require ruggedization for use in weapon systems. More cutting edge technologies such as superimposing high bandwidth Fibre Channel data communications on top of DC power signals show promise but will require significant maturation before being adopted. This paper will describe the role of these emerging technologies in meeting key requirements of the MRL.

2 Introduction A Smarter Launcher for Smarter Rockets 2.75-inch rockets are a key multi-mission weapon system for the joint force. These rockets have long provided both U.S. and international forces with anti-materiel, anti-personnel, air-to-ground suppression, smoke-screening, and illumination capabilities. Until now, rockets have been strictly ballistic weapons with no active navigation and control capabilities, but this situation is changing as advanced guidance technology migrates downward from larger, more expensive missiles to smaller and cheaper guided 2.75-inch rockets. New technologies being incorporated into guided rockets and digital fuzes cannot be fully utilized using existing M260 and M261 rocket launchers and these existing launchers cannot be retrofitted to support these technologies. To support these new technologies, a new Modernized Rocket Launcher (MRL) will provide nonproprietary, open architecture interfaces to host platforms and new guided and unguided rockets while maintaining backwards compatibility with the family of legacy 2.75-inch rockets. The MRL is intended for use with all rotary wing MIL-STD-1760 platforms such as the Army s AH-64D Apache and OH-58D Kiowa Warrior, and the Navy s AH-1Z Cobra and MH-60 Seahawk. The U.S. Army Aviation and Missile Research and Development Center (AMRDEC) is working with the Joint Attack Munition Systems (JAMS) Program Office to identify and mature the technologies that will be needed to realize the MRL vision. 1 Yourfilename.ppt

3 Technology Overview Broad System Capabilities Require a Broad Range of Technologies Launcher Electronics Data Over Power High and Low Bandwidth Data ARID (Zoneless Firing) Aircraft MIL-STD-1760E/ MIL-STD-1553B Fuze Contact Band Motor Contact Band Rotainer The technologies being explored for use in the MRL cover a range of maturities. New 2.75-inch rockets will use existing rocket motors and existing motor control technologies will be carried forward. Some legacy rockets utilize analog fuzes with plug in wired connections to the launcher. To support legacy rockets the MRL must support legacy fuze connections, even as they undergo continuing upgrades to meet current operational needs. Improved mixed munition loading flexibility will result from the ability of the MRL to automatically identify the type and tube location of each loaded rocket. Commercial technologies such as Radio Frequency Identification (RFID) or 1- Wire communications are candidates for meeting this requirement. Digital communications between the platform, MRL, and new guided rockets provide enhanced weapon system command and control. Existing MIL-STD-1760 and MIL-STD-1553 technologies will define the platform to MRL interface and Society of Automotive Engineers (SAE) avionics standards and technical reports offer possible definitions of the MRL to munition interface and proposed methods for superimposing data communications on top of DC power signals. To handle the range of complexity anticipated in future guided rockets, the MRL may provide both high and low bandwidth communications to the munitions. Fibre Channel networking technology, with its established success in the commercial world, is the leading candidate for providing high bandwidth communications. Low bandwidth communications could be provided through an EIA-422 or EIA-485- based serial protocol. * 1-Wire is a registered trademark of Dallas Semiconductors. 2 Yourfilename.ppt

4 Established Technologies, Proven Applications Use What Already Works Although future rockets will use new guidance and control technologies, they will continue to use the current MK 66 family of rocket motors. These motors are ignited through a contact band at the aft end. A rotainer assembly attached to the rocket tube acts to both retain the rocket in the launch tube and route the motor ignition signal through spring loaded electrical contacts to the motor ignition band. An updated rotainer assembly will be incorporated into the MRL, but the fundamental technology is well established and will not be significantly altered. The platform to MRL electrical interface will be MIL-STD-1760E. The MIL-STD-1760 interface includes a MIL-STD-1553 data bus for reliable real-time data communications between an aircraft and its stores such as launchers and weapons. The MIL-STD-1760/1553 interface is a mature, open standard that has been used for decades on military avionics systems, including the existing HELLFIRE guided missile weapon system. Because most of the MRL s target platforms are capable of carrying both HELLFIRE missiles and 2.75-inch rockets, standardizing on the MIL-STD-1760 interface for the MRL will allow platforms to use a single interface for both weapon systems. This allows platforms to eliminate the proprietary electronics and cabling associated with existing legacy rocket launchers, thus saving parasitic weight and space on the platform. 3 Yourfilename.ppt

5 Established Technologies, New Applications Use Old Technologies in New Ways The use of spring loaded electrical contacts is old technology. It is used to ignite the motors of 2.75-inch rockets in today s launchers and will be used in the MRL for the same purpose. The same technology may be used in the MRL to supply an electrical path for digital communications between the launcher and new digital fuzes that may replace the analog fuzes used on some rockets. The biggest problem facing this technology application is dealing with the movement of the rocket within its tube during flight. Although the movement is slight, it is sufficient to briefly break electrical continuity between a tubemounted electrical contact and a rocket-mounted fuze contact band. Temporary loss of continuity is not a significant problem when spring loaded contacts are used to carry analog ignition signals to the rocket motor, but loss of continuity is a significant problem when the contacts are used to carry digital signals to the rocket fuze. Fuze Contact Band Despite the sophistication of modern guidance technologies, the amount of direct communication needed to control munitions utilizing these technologies is often small. In these cases, simple low bandwidth serial communications using well understood and widely supported protocols are adequate. Other more sophisticated munitions will need to use the high bandwidth communications supplied by the MRL. The MRL may be configured to carry up to 24 rockets, thus the need to limit the number of wires going to any one rocket is critical. One method of accomplishing this is to have different signals share conductors, such as using the same signal path for both high and low bandwidth communications or superimposing digital data on power signals. 4 Yourfilename.ppt

6 Commercial Technologies, Military Applications Push The Envelope With Existing Technologies Rockets are classified by their warhead type such as high explosive, flechette, smoke, or illumination. When an existing launcher is to be loaded with multiple rocket types, each type must be loaded into specific sets of launcher tubes, called zones. Only rockets of a single type can be loaded into a particular zone. This zoned inventory is then manually entered into the aircraft s weapons computer. To improve operational flexibility and reduce operator error, the MRL will automatically determine the type of rocket in any tube and allow firing of any type of rocket from any tube at any time. This capability is known as zoneless firing. Automatic rocket identification (ARID) is the key to enabling zoneless firing. ARID refers to any means whereby sensors associated with each launcher tube read a signature tag, or identifying mark, on a rocket to determine the rocket s type. Because ARID must work with both legacy and emerging smart rockets, it must operate properly on unpowered rockets. Additional constraints include the space available for sensors and wires within the MRL structure and the ability to retrofit the technology onto rockets currently in inventory. ARID candidate technologies include established commercial techniques such as RFID, bar coding, or 1-Wire data communications. However, incorporating these technologies into a rocket launcher environment poses new challenges. These challenges include rocket backblast at launch, exhaust residue accumulation in the tube and on the launcher face, and tube scoring that results from rocket loading, launch, and tube cleaning. Sensors will also be subjected to the extreme environmental conditions, high vibration, and electronic noise inherent in military aircraft applications. 5 Yourfilename.ppt

7 Blended Technologies, Military Applications Combine The Best From Both Worlds Fibre Channel is an established high speed communication protocol widely used commercially to connect host processors to secondary storage devices such as disk and tape drives. Offering speeds up to 8.5 Gigabaud, Fibre Channel acts as the underlying carrier for a variety of upper layer data protocols such as Small Computer System Interface (SCSI) or Asynchronous Transfer Mode (ATM). It has been used in several military aircraft including the F-16, F/A-18, F-35, and B-2. SCSI over Fibre Channel Mil-STD-1553 over Fibre Channel MIL-STD-1553 is a 37-year old standard that defines a physical bus and logical protocol for redundant, reliable data communications and has been used extensively in both military and NASA aerospace applications. MIL-STD-1553 offers high reliability but suffers from low bandwidth. As increasingly sophisticated munitions produce and consume increasing amounts of data, the 1 Mbs limit of MIL-STD-1553 poses severe limitations. SAE has produced the FC-AE-1553 Technical Report that defines how the logical messaging of MIL-STD-1553 can be combined with the physical transport of Fibre Channel to provide a new high speed communications capability. This new capability would preserve the avionics community s investment in MIL-STD-1553 technology while overcoming MIL-STD-1553 s bandwidth limitation. SAE standard AS5653 High Speed Network for MIL-STD-1760 tailors FC-AE-1553 for use within the MIL-STD-1760 interface used by modern weapon systems. AS5653 and FC-AE-1553 are both relatively new, with little hardware or firmware support from commercial vendors. If these standards are to be incorporated into the MRL, they will require a technology maturation effort that occurs in parallel with launcher system development. 6 Yourfilename.ppt

8 Emerging Technologies, Emerging Weapons Will That Work? Isolation Network The SAE has released standard AS5726 Interface to Micro- Munitions (IMM) that defines the electrical and logical interfaces between launchers and micro-munitions. Micro-munitions are defined generally as munitions weighing less than 50 pounds, a definition that includes 2.75-inch rockets. IMM is a candidate for the MRL to munition interface for this reason. IMM specifies seven conductors between launcher and munition, but to achieve this low conductor count IMM assigns multiple signals to some conductors. In particular, it transmits both high bandwidth AS5653-based data communications and DC power over the same conductors. This saves four conductors but introduces considerable technical complexity. IMM is a new interface that has yet to be implemented on any weapon system. FC Driver or Receiver Internal Fibre Channel Port fct fct Internal DC power port DC Source or - Load + Power/FC_H Interface Port Power Return/ FC_L A second drawback of IMM in the context of the MRL is IMM s lack of a low bandwidth data path between launcher and munitions. The AS5653 Fibre Channel-based communications specified by IMM are capable but costly and complex. Most emerging smart rockets have simple communication needs and would not benefit from the added cost and complexity of IMM s high bandwidth communications. A key research focus for the MRL is to develop a low bandwidth communications capability that can supplement IMM s high bandwidth capability without significantly increasing signal set size, electrical complexity, cost, or weight. One of the most attractive aspects of the MRL system is the relatively low cost of 2.75-inch rockets relative to larger missiles. Offering a less costly low bandwidth communications option between launcher and munitions will help control the cost of emerging smart rockets. DC Operating Power/ Down Fibre Channel+ Operating Power Return/ Down Fibre Channel- Safety Enable Power/ Up Fibre Channel+ Safety Enable Power Return/ Up Fibre Channel- Safety Enable Discrete Mated Discrete Structure Ground Figures from SAE AS Yourfilename.ppt

9 Conclusion Where Things Stand Today The different candidate technologies envisioned for the MRL are at different levels of maturity and present different levels of risk. AMRDEC and the JAMS Program Office are working to identify and mitigate the risks associated with candidate technologies while providing a flexible growth path for future smart rockets. The areas being actively explored in AMRDEC labs today include the emerging technologies identified earlier: putting digital data on top of analog power signals, maturing the AS5653 high speed data communications standard, and supplementing the MRL s high bandwidth communications capability with a lower cost, lower bandwidth alternative. Prototypes have been built that implement the Fibre Channel digital data over DC power requirements specified by IMM. Additional prototypes have been created that superimpose a lower speed serial digital data stream over DC power. The lower speed serial stream employs a protocol similar to the EIA-422 and EIA-485 protocols that have long been used in both military and civilian applications. The maturation of AS5653 communications is being performed in conjunction with the JAMS Program Office. A Fibre Channel Test Bed facility is under construction at AMRDEC that combines commercial and first generation military Avionics Environment (AE) Fiber Channel hardware with custom software to provide a high fidelity Hardware-inthe-Loop test and verification capability for emerging smart rockets and missiles. AIM-USA Fibre Channel Analyzer. 8 Yourfilename.ppt