By Edward J. Walsh
Electronic equipment from Litton Marine Systems helped automate bridge functions aboard the first U.S. Navy "smart ship."
Systems to automate navigation and other functions aboard the Arleigh Burke-class destroyers are to be the centerpiece of the U.S. Navy's so-called "Smart Ship" program to integrate shipboard electronics with hull, mechanical, and command-and-control tasks
One of the U.S. Navy's newest families of surface warships, the Arleigh-Burke-class (DDG 51) guided-missile destroyer, is to receive an integrated bridge system (IBS) this year to automate all navigation-management functions.
The move to the IBS for the Burkes would be the centerpiece of several upgrades under consideration to introduce a so-called "Smart Ship" configuration for ship-systems controls that will integrate with hull, mechanical, and electrical systems, as well as with combat and command and control systems. Officials of the Navy's program executive office for theater surface combatants plan this spring to select integrated bridge systems for the Burke class of Aegis destroyers.
The Burke-class destroyers, however, are not the only bright spot where shipboard electronics integration is concerned. Through 2000 Navy leaders achieved important progress in the integration of navigation and ship controls with other ship systems for surface combatants, amphibious ships, and aircraft carriers. They made progress in these areas — including combat systems — despite funding constraints that limited progress in key areas of new ship-systems development.
The latest generation of bridge electronics eases the tasks of watchstanders with features such as digitized charts and navigational information shown on shipboard displays.
For future ship programs, meanwhile, shipboard electronics designers will automate bridge-management functions primarily through advanced software. These programs will involve the San Antonio-class (LPD 17) amphibious assault ship, Zumwalt-class (DD 21) land-attack destroyer, Virginia-class (SSN 774) attack submarine, and future aircraft carriers.
For the DD 21, an integrated bridge system will be an element of a tightly coupled total-ship computing environment. Competition is keen among the two industry teams vying to build the future DD 21 land-attack destroyer. The ultimate winner will reap a big payoff in electronics development and production.
The industry groups competing to build the DD 21 are called the Blue Team and the Gold Team. Leading the Blues are General Dynamics Bath Iron Works in Bath, Me., and Lockheed Martin Naval Electronics & Sensor Systems-Moorestown in Moorestown, N.J. Leading the Golds are Litton Ingalls Shipbuilding of Pascagoula, Miss., and Raytheon Naval and Maritime Integrated Systems in Portsmouth, R.I. These teams may select IBS technology from either Litton Marine Systems in Charlottesville, Va., or Raytheon Marine Co. of Nashua, N.H. — the two primary builders of bridge systems for the Navy.
Bridge systems aboard all future ships are to link closely to ship-control systems and eventually to combat systems via advanced shipwide fiber-optic networks. Supporting future electronic architectures, which will include integrated bridge systems, will be variants of the AN/UYQ-70 advanced display processor console from an industry team led by Lockheed Martin Naval & Surveillance Systems-Eagan in Eagan, Minn.
The 'Q-70, now going into service on surface combatants, aircraft carriers, amphibious ships, submarines, and maritime patrol aircraft, will provide the baseline for the introduction of commercial processors for many computing tasks, including ship navigation. Lockheed Martin engineers currently are shifting the 'Q-70 from its original Hewlett-Packard HP 743 and HP 744 microprocessor architecture and HP Unix operating system, to Sun UltraSparc II and Motorola PowerPC and Solaris operating system, although it will continue to accommodate the early architecture.
Integrated bridge systems
Navy leaders also expect by late this year to certify Raytheon Marine and Litton Marine for compliance with a Navy-unique version of Electronic Charting Display Information System-Navy, referred to as ECDIS-N. Northrop Grumman Corp. in Los Angeles is acquiring Litton Marine, along with the rest of Litton.
The ECDIS chart-reading capability is based on standards developed during the mid-1990s at the International Maritime Organization with support from industry. ECDIS software enables a host computer, which could be a PC, to display charts and provide navigation functions. The Navy in March 1998 announced a goal of 2007 for fully shifting to a "paperless" ECDIS-N navigation suite for the entire fleet.
For Litton and Raytheon, the Navy IBS business is a small element of their worldwide business supplying bridge systems to commercial tankers, commercial ships, and freighters, as well as providing training and logistics support.
An IBS provides navigation management by linking voyage planning system software, which runs on bridge consoles, with ship steering and navigation radars. The IBS approach makes the navigational data appear on displays on the ship's bridge and in other ship spaces, including the captain's stateroom and in the combat information center (CIC) aboard Navy warships. Integrated bridge systems also include an automatic radar plotting aid (ARPA), which interfaces with the ECDIS and displays ECDIS data.
Integrated bridge systems provide not only voyage and route planning with navigation and steering control, but also the graphic interface for situational awareness of the navigation environment. They also eliminate the need for meticulously plotting courses on paper charts and, as commercial operations have shown, reduce manning requirements for bridge watchstanders.
Leaders of the Navy's Arleigh Burke program office (PMS-400D) remain strongly interested in introducing a full-up IBS despite the failure of a "Smart Ship" engineering controls systems equipment (ECSE) acquisition program that included installation of an IBS for the Ticonderoga-class (CG-47) Aegis cruisers.
Lessons learned
In early January the Navy and the ECSE prime contractor, Litton Guidance & Controls, agreed to modify Litton's contract to end Litton's role in the program after the first four ships and transfer that role to the Naval Ship Systems Engineering Site (NAVSSES) in Philadelphia. For those four ships, Litton Guidance installed a Litton Marine IBS. The Aegis program office started to produce a statement of work for a similar Smart-Ship program for the Burkes that would have included an IBS. That program has been dropped.
Litton Marine supplied the automated bridge system, including its voyage management system (VMS) software, for the Navy's initial "Smart Ship" program for the Aegis cruiser USS Yorktown (CG-48). Litton also has built integrated bridge systems for the aircraft carrier USS Harry S. Truman (CVN-75), the amphibious assault ship USS Iwo Jima (LHD-7) as well as the Cyclone-class (PC-1) patrol ships, the Navy's landing craft air-cushion (LCACs), and Los Angeles-class attack submarines.
Litton also supplied bridge hardware and software, although without full integration of its voyage management system and steering control, to the carriers USS George Washington and John C. Stennis (CVNs-73 and -74). The company is under contract to provide the IBS for the 12 planned new-build San Antonio-class (LPD-17) amphibious assault ships. The San Antonio is under construction at Litton Avondale's New Orleans shipyard. Litton also recently installed a partial three-node IBS aboard the fleet command ship USS LaSalle (AGF-3)
Raytheon has sold some 200 IBS systems to commercial customers. Its engineers built the system aboard the "Smart Gator," the Whidbey Island-class amphibious assault ship USS Rushmore (LSD-47). In spring 2000 the Navy, citing funding constraints, canceled a planned release of a request for proposals for an industry competition to provide Smart Gator systems, including the IBS, for the rest of the Whidbey Island class.
Raytheon has delivered a full IBS to the Naval Ship Systems Engineering Site (NAVSSES) in Philadelphia. The company has provided its Pathfinder navigation radar and ARPA and ECDIS software to most of the Navy's carriers and Wasp-class (LHD-1) amphibs, and for shore-based installations at the Navy's surface warfare officer's school and the National Imagery and Mapping Agency (NIMA). Raytheon supplied the ECDIS, integrated with the SPS-73 navigation radar, to the Wasp as well as the USS Pearl Harbor (LSD-52) and the auxiliary Bridge (AOE-10).
Leaders of BAE Systems, prime contractor for the U.K. Royal Navy's new-build T45(D) air-defense frigates, announced in late 2000 that the class would be fitted out with the Raytheon IBS. Raytheon also provides bridge and navigation systems, although not full IBSs, to the German, Greek, and South Korean navies.
Automated bridge equipment can network engine and navigational information throughout the ship — including to the captain's stateroom.
Raytheon Marine also has provided for early (Flight 1) Arleigh Burke-class Aegis destroyer (DDGs-51 through -67) its Pathfinder ARPA software through an upgraded configuration of the SPS-64 navigation radar. The company's Pathfinder/ARPA software is in service aboard the Navy's non-nuclear carriers (CVs 63, 64, and 67), Nimitz-class carriers CVNs-68 through -74, five Avenger-class (MCM-1) minehunters, as well as 30 Military Sealift Command support ships and 30 Maritime Administration replenishment vessels.
The Raytheon Pathfinder ECDIS system provides real-time situational awareness, own-ship position in relation to tracked targets, on-screen conning information, and anti-grounding visual and audio alarms. The system displays the targets that ARPA tracks. Four Pathfinder ARPAs may be interfaced and linked to the ship's navigation radar. It also provides route and data exchange between the Pathfinder ARPA and ECDIS, on-screen route planning and text editing, and reading of internationally certified vector digital charts, man overboard, and range and bearing displays for any point on a chart.
Raytheon officials say that their ECDIS software is a "fusion engine" that combines ship's dynamic model, planning route and geographic data, real-time position and attitude sensors, radar surface plots, and sub-surface sonar data. Company officials say that their ARPA provides true target tracks to the ECDIS software, and links with Navy's SPS-55, SPS-64, and SPS-67 navigation radars.
Tom Otterbein, senior program manager at Litton Marine and former commanding officer of the carrier Truman, says that the Litton IBS is a "software-centric" navigation architecture that runs on ship's computers, mainly configurations of the UYQ-70. He says that the Litton VMS, called Vision Technology 2100 or VT2100, runs on any Intel-based computer. The company newest IBS variant is designated the VISION 2100M. The system consoles link to navigation systems, which include navigation radars, global positioning system receivers, a Doppler sonar velocity log, the UQN-4/4A fathometer, and inertial navigation systems (INS).
The Navy currently fields a mix of inertial navigation systems, all built by Litton Marine, including the WSN-1 (carriers), WSN-3 (submarines), WSN-5 (surface combatants), and all based on ring-laser gyroscope technology. The Navy now is fielding an enhanced WSN-7(v) that will replace the currently fielded systems.
The IBS data flows over standard shipboard interfaces, which range from new fiber-optic local-area networks to MIL-STD 1553 databuses and Ethernet and other interfaces.
"The software provides the IBS functionality," Otterbein says, who while on active duty oversaw the installation of the IBS aboard the Truman. The VMS software provides the ECDIS navigation capability, based on the use of a universal chart manager that reads official electronic charts from the National Oceanographic and Atmospheric Agency or NOAA, the British Admiralty, and the Canadian Hydrographic Service. VMS provides for display of "conning" data that encompasses navigation, maneuvering, machinery, and alarm status, as well as menu controls and radar overlay functionality.
The system, when loaded with data on a planned course, creates a file that provides the voyage solution. Otterbein says that the plan file consists of geographic, latitudinal, and longitudinal waypoints and the precise course track to be steered. When the ship embarks, a voyage-plan execution module receives instructions on which plan to load.
He points out that because of traffic or other factors the ship may be several miles down the course before the plan actually engages. The helmsman then executes a "return to plan" function, and the VMS starts navigating. Because software drives the system, bridge personnel can modify VMS courses within minutes. The VMS records position fixes every 15 seconds, and is capable of a one-second recording pace.
Otterbein points out that IBS data can travel on nearly any shipwide network. On new ships, beginning with the San Antonio class, the IBS will be a node on a shipwide area network (SWAN). Navy and industry officials say this network will act as a data highway infrastructure linking several different ship systems, including the Raytheon-built SPS-73 radar, the ship's primary navigation sensor. The SWAN also links damage control, shipboard integrated condition assessment, and fuel and engine control. IBS data will be available, via the SWAN, to any multifunction workstation on the network.
The San Antonio SWAN originally was designed also to link combat systems. Because of concerns by combat-systems program managers and fleet operators about the potential danger of combat-systems data held up by network latency, officials in the ship's program office retreated from the concept. Combat systems are networked separately for the class.
For the Arleigh Burkes, the IBS would link to ship systems by a data multiplex system installed on the Flight 1 and Flight 2 ships (DDGs-51 through '78) and the Fiber Optic Digital Multiplex System, to be installed on the Flight 2A ships starting with the Oscar Austin (DDG-79). Boeing Naval and Marine Systems in Anaheim, Calif., and Sierra Technologies of Buffalo, N.Y., share production of the FODMS.
Otterbein says that for older ships, the Litton IBS includes a suite of computers linked on a fiber-optic network. The system hardware consists of "building blocks" that vary among ship configurations, but typically include a planning station, navigation station that hosts the ECDIS software, a conning display, autopilot steering control system, Bridgemaster E radar system, ring-laser gyro INS, speed log, and data-communications network.
The architecture represents some degree of integration, but is primarily a federated system than can include interfaces to the radar as well as to steering control. Aboard the Truman, the bridge consoles also provides alarms based on serial interface links to the ship's damage control system.
The IBS interface to the navigation systems comes from a Navy-unique system developed by the Shipboard Integration office (PMW-187) of the Navy's Space and Naval Warfare Systems Command (SPAWAR), designated the AN/SSN-6 Navigation Sensor System Interface (NAVSSI).
Litton Data Systems and ACS Technologies Inc., both in San Diego, provide NAVSSI software support to SPAWAR. The NAVSSI also displays digital nautical chart (DNC) data from the National Imagery and Mapping Agency (NIMA) for use by bridge watchstanders.
The SPAWAR-developed NAVSSI generates data that provides precise time, position, velocity, acceleration, roll, pitch, and heading; GPS receiver initialization, course, speed-over-ground, true and relative wind, speed, direction, and depth below keel. The system uses SPAWAR-developed correlation software to select, integrate, and format data for use by ships' weapon-system computers for targeting functions.
SPAWAR officials are upgrading the NAVSSI through an evolutionary series of blocks that eventually will extend to ship gun systems, and self-defense missiles. Aboard cruisers and destroyers NAVSSI will help control Tomahawk cruise missiles, handle command, control, communications, and intelligence (C4I) and navigation, as well as ship-control systems like IBS. Currently, PMW-187 leaders developing NAVSSI links for data provided by video cameras.
NAVSSI block 2 and block 3 systems are in service aboard some 72 ships, including Ticonderoga-class cruisers, Spruance-class (DD 963) destroyers, several aircraft carriers, Arleigh Burke-class destroyers, and the amphibious assault ship USS Tarawa (LHA-1). An early block 0 version linked with the Tomahawk weapon system.
Block 2, meanwhile, provides basic navigation translation and processing functions. Block 3, developed through a memorandum of understanding with the U.S. Coast Guard, introduced functionality for the Defense Information Infrastructure Common Operating Environment (DII COE). SPAWAR officials are completing development testing for NAVSSI block 3, which will extend NAVSSI functions to additional weapon systems.
The block 3 is being fielded in two "builds," referred to as build 2 and build 4, and future upgrades will incorporate the latest Tomahawk variant — the block 4 "tactical Tomahawk" — as well as the ship self-defense system (SSDS Mk 2) new guns such as the Mk 160 gun system, which controls the new Mk 45 mod 4 five-inch .62 cal. deck gun.
Both system variants provide displays for the chart room and the bridge. SPAWAR PMW-187 officials say that eventually they will also provide a NAVSSI display in the combat information center.
Navigation Sensor System Interface
The NAVSSI consists of a real-time subsystem (RTS), display and control subsystem (DCS) and a remote station installed on the ship's bridge. The RTS, installed in the forward gyro space, uses Hawke data interface boards from Sabtech Industries Inc. of Yorba Linda, Calif., that accept data from the ship's navigation sensors.
The RTS carries out the correlation and integration of the data that flows to ship systems from either point-to-point interfaces or from a local-area network. Aboard aircraft carriers the NAVSSI is an interface to the integrated communications and navigation network architecture that links aircraft carrier internal control and communications systems. The NAVSSI also will interfaced to the shipboard IT-21 LAN, called the integrated shipboard network system now being fielded.
The system, through build 4, is to connect to 42 weapon, C4I, and other systems. The block 3 build 4 upgrade will add a new VME GPS receiver card to the RTS, replacing an older satellite signal set receiver system and improved capability for displaying electronic charting. The DCS, installed in the ship's chartroom, provides overall system control and displays digital-nautical chart data on a 19-inch bridge workstation.
The DCS interface to the DII COE supports the navigation planning carried out by the IBS, based on the use of the digital nautical charts. NAVSSI also provides a link to the Navy's global command and control system-maritime for integration of wide-area command and control data.
Industry and Navy officials stress that NAVSSI is to be a source of integrated navigation data for use by weapons and specialized ship systems. Lt. Cmdr. Greg DeVogel, assistant manager for electronic charting in PMS-187, points out that NAVSSI is intended primarily to provide signals to the weapon systems, although it also displays electronic charts on the bridge. He emphasizes though that the system is not intended to function as an integrated bridge that calculates courses and provides navigation updates. Litton officials say also that their IBS is not designed to provide navigation data to weapon systems. They stress that the NAVSSI as a provider of data is an asset to the IBS installation.
Litton first developed a navigation data interface to link the company-built IBS for the Yorktown Smart Ship project. The company used an RS-422 serial interface provided by SPAWAR provided for the NAVSSI RTS for translating the navigation system data into a format compliant with the Naval Maritime Electronics Association's (NMEA 0183) standard. For the San Antonio configuration, the company has established communications with the NAVSSI over the SWAN.
Some Navy ship program officials reportedly have considered the NAVSSI capable of carrying out full management of navigation functions. The NAVSSI's block 3 build 4 configuration runs a software program called COMDAC-INS — short for command display and control-inertial navigation system — developed by Lockheed Martin Naval Electronic & Sensor Systems (now BAE Systems) in Manassas, Va., for the Coast Guard. The COMDAC-INS provides some navigation functions similar to those of an IBS.
Officials of the Naval Sea Systems Command's aircraft carrier program office selected the NAVSSI to carry out navigation-control functions for the new-build carrier USS Ronald Reagan (CVN-76), after they had installed the Litton-built IBS aboard the Truman and partly integrated systems, linked to the NAVSSI, aboard CVNs 73 and 74.
The Ticonderoga-class cruisers scheduled to get the Litton IBS through the Smart Ship program also are equipped with NAVSSI.
Litton and Raytheon officials say they expect to receive Navy ECDIS-N certification from NIMA for their respective IBS software, the Litton VT 2100 and Raytheon Pathfinder Mk 2, by late summer or early fall. SPAWAR officials say that NAVSSI also will be certified as ECDIS-N compliant probably late this year.
The Navy's ECDIS-N according to the March 1998 Chief of Naval Operations policy letter, aims at shifting the fleet from the use of paper charts to an all-electric charting capability as defined by NIMA.
ECDIS-N is to be a common Navy ship standard, to which commercial ECDIS systems must comply. ECDIS-N lays out standards for precise levels of navigation accuracy such as line-of-position fixes, dead reckoning, and radar and visual reads. In September 2000, Litton officials said their VT 2000 VMS had received commercial ECDIS certification from Det Norske Veritas, a Norway-based commercial certification organization. Raytheon early this year planned to submit its Pathfinder to the International Maritime Organization for certification, which it says, will be a "first step" towards ECDIS-N compliance.
Litton and Raytheon engineers are adapting their commercial ECDIS to be easily modified to meet the ECDIS-N requirements. They point out, though, that in late 2000 the NIMA had not completed development of elements of the ECDIS-N specification, including a "presentation library" called GeoSym 4.
A key criterion for compliance is compatibility with "direct-read" software that will easily display electronic charts. Raytheon and Litton officials say, however, that Navy standards for "direct read" have not been completed. Both companies meanwhile are adapting their commercial ECDIS to be easily modified to meet the ECDIS-N requirements.
