Solutions Group

A 3D Interface to Access Ship Data

A White Paper

Intergraph Solutions Group White Paper

A 3D Interface to Access Ship Data

A 3D Interface to Access Ship Data

Intergraph Solutions Group White Paper

Table of Contents

Abstract .................................................................................................................................................... Page ii 1. Challenges of Technical Data Access ..................................................................................................... Page 1 1.1. Existing 3D Graphics Interfaces ..................................................................................................... Page 1 1.2. Intergraph 3D Virtual Interface: myShipVI..................................................................................... Page 2 2. Background ........................................................................................................................................... Page 2 2.1. 3D Virtual Interface Concept ......................................................................................................... Page 2 2.2. PDM Interoperability Program ....................................................................................................... Page 3 2.3. LPD 17 ........................................................................................................................................... Page 3 2.4. 3D Virtual Interface Requirements................................................................................................. Page 4 3. Functionality .......................................................................................................................................... Page 4 3.1. Ship Model .................................................................................................................................... Page 4 3.2. User Interface / Navigation............................................................................................................ Page 4 3.3. Walkthrough Mode........................................................................................................................ Page 5 3.4. Controlling the Display .................................................................................................................. Page 5 3.5. Accessing Data .............................................................................................................................. Page 6 4. Implementation ..................................................................................................................................... Page 7 4.1. Architecture ................................................................................................................................... Page 7 4.2. Interoperability Framework ........................................................................................................... Page 7 4.3. Graphic Rendering Engine ............................................................................................................. Page 8 4.4. myShipVI Application..................................................................................................................... Page 8 4.5. Creating 3D Interface Graphics from CAD Files ............................................................................. Page 8 4.6. Creating 3D Interface Graphics for Legacy Ships Without CAD Models......................................... Page 9 5. Technical Challenges ............................................................................................................................. Page 9 5.1. Performance .................................................................................................................................. Page 9 5.2. Automated Conversion of CAD Graphics ....................................................................................... Page 9 5.3. Level of Detail................................................................................................................................ Page 10 5.4. Model Validation........................................................................................................................... Page 10 6. Summary................................................................................................................................................ Page 10 Nomenclature ............................................................................................................................................ Page 12 Notes ......................................................................................................................................................... Page 14

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A 3D Interface to Access Ship Data

Intergraph Solutions Group White Paper

Abstract This white paper discusses the development of an interactive 3D graphical interface, myShipVI™, which provides a simple and intuitive method to access integrated ship data through a first-person perspective interface, similar to some computer games. 2D drawings and/or a 3D CAD ship model provide the user with an accurate spatial rendering of the ship. The result is a “virtual interface” of the ship, which allows the user to move through the virtual ship and retrieve information via point and click. Once the user touches a specific component or piece of equipment, the interface displays key data and a list of related document links (tech manuals, training documents, diagrams, maintenance procedures, parts lists, maintenance schedule/records, etc.). Documents can then be viewed by simply clicking on the links. Further information can be obtained or other actions triggered by clicking selected buttons in the interface. Users can also navigate quickly using a product tree or 2D overlay of the ship. The 2D overlay displays a crosssection centerline profile of all deck elevations as well as the compartment arrangement for a selected deck. A product tree captures a deck, compartment, and equipment breakdown. Users can “jump” to a selected compartment or piece of equipment. This interface allows the end user to quickly and easily find the required data as well as familiarize them with the ship. myShipVI is implemented as a Web application, using off-the-shelf hardware and software to access ship models, data, and documents on the server. It is built upon a graphic-rendering engine utilizing texture-mapped polygons for performance. The server accesses data and documents from multiple sources through the myShipI/F, which integrates the resultant data. Prepared by: Ted L. Briggs and Stephen J. Baum, Intergraph Solutions Group Presented at: The 2003 World Maritime Conference, October 17-20, 2003, San Francisco, CA

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virtual interface that can access ship data and run on off-the-shelf hardware. This 3D virtual interface is intuitive and easy to use, especially for a generation of users already familiar with gaming interfaces.

1. Challenges of Technical Data Access A wide range of users across the shipbuilding enterprise now depend on Web access and availability of digital ship data to perform their daily duties. As increasingly larger quantities of ship data become available digitally, the end user often finds it difficult to locate the data they require for several reasons.

1.1. Existing 3D Graphics Interfaces Most existing 3D graphic interfaces support only graphical operations and cannot be used as a 3D virtual interface to access ship data. A quick review of the existing categories of 3D graphical tools reveals some of their limitations.

First, it is difficult for the causal user to quickly and easily navigate through volumes of data to find what is of importance (and once found, later return). Simple keyword searches based on textual queries are often frustrating to the user and are regularly unsuccessful due to the lack of data standardization. Users are limited by their inability to search within a specified context, such as a system or compartment.

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Simple graphic file viewers Graphic file viewers have been developed for many different graphic formats, such as Virtual Reality Modeling Language (VRML), Standard for the Exchange of Product Model Data (STEP), Initial Graphics Exchange Specification (IGES), and Alan Charles Ian Spatial (ACIS). However, these viewers typically display only the contents of a single file, not an entire ship. Furthermore, they are restricted to simple graphical manipulations and do not permit access to properties or associated documents. Viewers generally do, however, support Web access.

Second, data tends to be distributed across a number of disparate data systems that typically do not communicate or interoperate and are often “out of synch.” The user is then required to log into each data system individually, retrieve the data, and then manually integrate and validate the data. These problems typically apply to end users across the ship’s life cycle, including designers, planners, logisticians, production workers, and sailors.

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CAD walkthrough tools Most CAD tool suites include a walk-through tool, which allows the user to walkthrough a file or limited portions of a model. Typically, these tools only expose data that resides in the CAD file, not documents or associated data in other systems. Additionally, these tools are available only as applications that must run on the client, not as Web applications. Performance may be limited due to the use of CAD graphics formats. Users often require training and access is usually limited to engineering and production users.

A 3D graphical interface can provide a simple, intuitive method to assimilate and access data. This is particularly true for an interface based upon a firstperson perspective (FPP), in which the user can virtually navigate throughout a ship and retrieve information about equipment and components from multiple data systems. This type of interface is called a virtual interface. Previously, such interfaces have been restricted to specialized hardware and applications, e.g. virtual reality tools. Although 3D computer-aided design (CAD) models are generally available for most new ship designs, the 3D model is rarely available to untrained end users or sailors onboard ship. In contrast, computer games and simulations have become increasingly sophisticated and widespread with more realistic (high fidelity) graphics, FPP interfaces, and evolving Web-based access. The availability of such rendering technology has enabled the development of a 3D

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Simulation tools Most CAD tool suites support simulation tools that allow users to interact with the 3D model, e.g. IGRIP from Delmia. These tools are even less suitable for Web access and often require high-performance hardware. Simulations are frequently limited to a portion of the ship and

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Intergraph Solutions Group White Paper do not normally access external data. A trained staff may be required to develop the simulations and access to the simulations is often limited to engineering and production. These tools are also costly to procure and maintain. •

Virtual reality tools Virtual reality tools have limited availability and require specialized hardware. Potentially, they allow a user to access the entire ship, as well as external data sources. However, models may be difficult to create and the tools are typically very costly to procure and maintain.

At this time, only one other 3D virtual interface is known to be available. It is eBrowser from Elomatic4 and uses a native naval architectural package (NAPA) model.

Figure 1: Intergraph 3D Virtual Interface: myShipVI

A complete 3D walkthrough model has been created for the USS San Antonio (LPD 17) Class, based on an early design baseline. The resulting tessellated model encompasses 1,064 compartments and almost 104,000 individual part instances using 5,031 different catalog parts. External data and documents may be retrieved for functionally significant items (FSI) (approximately 33,000) which are tracked as Ship Configuration and Logistics Support Information (SCLSI) data as part of the ship’s configuration during its life cycle.

1.2. Intergraph 3D Virtual Interface: myShipVI™ Intergraph has developed a general-purpose, Webbased 3D interactive virtual interface for ship data called myShipVI™ (see Figure 1), which is based on a FPP and runs on off-the-shelf hardware and software. It is built on a graphic-rendering engine designed to support simulation and gaming. The 3D graphic interface enables a user to tour a virtual ship while providing access to the latest data from a variety of sources.

A partial 3D walkthrough model of the Torpedo Weapons Retriever (TWR) has also been created for public demonstration and use. The Navy released the complete set of TWR drawings2,3 for public distribution by the Navy to provide an example of an existing ship for data exchange. The screen shots in this paper are taken from the TWR ship model.

myShipVI is different than traditional modeling and simulation tools in that it is optimized to execute on a standard desktop or laptop. Today’s high-end simulation tools normally use an ONYX-class computer with 2-6 GB of RAM, multiple high-end processors, and graphics accelerators. myShipVI runs well on a minimum of a single 700 MHz processor and 512 MB RAM.

2. Background This section highlights the background of the Intergraph 3D virtual interface concept and its requirements, as well as the PDM Interoperability Program.

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scalable middleware solution, called the Interoperability Framework™, to provide interoperability within and across ships, facilities, depots, yards, and commands where the architecture would be applicable to other DOD and joint agencies.

2.1. 3D Virtual Interface Concept The original concept for a 3D virtual interface was an application that would allow users to be virtually placed in a 3D ship environment where all of the significant equipment is loaded and easily identifiable, just as they are on a physical ship. The display engine needed to offer simple navigation skills to the end user and allow the user to interactively touch items to retrieve pertinent related information.

2.3. LPD 17 Based on contract requirements, the USS San Antonio Class of amphibious ship uses an integrated product Data Environment (IPDE) for storing, accessing, and managing all the data for the design, construction, and life-cycle support of a ship5. The IPDE was designed and built with the ship life cycle in mind. It is anticipated that the IPDE will evolve from principally serving shipbuilding design and production to additionally serving maintenance, modernization, ship operations, ship alterations, and other out-of-production functions. In order to fully support this spectrum of work, the IPDE will ultimately have shore-based and shipboard components.

The 3D virtual application design also required an easy-to-use, simple-to-learn, intuitive interface. This led to the need for a FPP interface. The average age of a sailor on board a ship is 21 years old. The most common interface that 21-year-olds have experience with are Web search engines and games. The 3D virtual interface was designed and developed with these “mouse movements” in mind. Along with the 3D geometry, these FPP systems always contain an overlay system. Intergraph employs this overlay capability in their design to incorporate both a profile view of the ship and the corresponding deck plan. This implementation allows the user to quickly find their way to a compartment in the 3D world.

The shore-based IPDE is the primary source of nontactical configuration data delivered to the ship. For the first ship of the LPD 17 Class, applicable elements of this data will be delivered, via the Configuration Data Manager Database – Open Architecture (CDMDOA), to legacy systems such as the Naval Tactical Command Support System (NTCSS).

The 3D virtual interface provides a realistic visualization tool for querying ship information on decks, compartments, or equipment from a geometrically accurate 3D model or ship profile using the point and click method. Once a user locates and selects a piece of equipment or a specific component, he or she can retrieve associated documents (technical manuals, training documents, diagrams, maintenance procedures, parts lists, maintenance schedule/ records, etc.) residing in various systems (new and legacy) by clicking on hot links associated with the equipment.

Shipboard IPDE for LPD 17 introduces an additional unclassified, nontactical information resource into the existing ship system environment. It is initially a read-only reference system with minimal design and cost impact on the existing nontactical information systems and contains a subset of the shore-based IPDE data. The objective of shipboard IPDE is to provide rapid user access to centrally managed ship data. Shipboard operators access shipboard IPDE data through the ship wide area network (SWAN) using existing, non-classified Microsoft® Windows NT® workstations. In addition, workstations can be designated for special purpose access, such as drawing redlines, administrating servers and databases, etc.

2.2. PDM Interoperability Program Development of the 3D virtual interface was partially funded by the PDM Interoperability Program, which is implementing a framework to support interoperability within the Navy and ultimately the Department of Defense (DOD). The Program is led by Intergraph and sponsored by the U.S. Naval Sea Systems Command (NAVSEA) 04L with the participation of the LPD 17 program office (PMS317). The goal of the Program is to develop an extensible,

Shipboard IPDE has the capability to improve onboard maintenance processes and help resolve ship configuration issues. These capabilities will increase the efficiency of work efforts aboard ship and will help to ensure the accuracy of shipboard information.

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Moreover, in addition to the realism, the sailors and Marines benefit from a tool that provides familiarization training and aids in the personnel certification process. Statistics show that more than half of the LPD 17 crew will be recent arrivals onboard prior to the start of any major deployment. For new ships, a crew can be assigned up to two years in advance. This application can provide familiarization with the vessel before it is built.

However, if the shipboard IPDE is not intuitive and easy to use, sailors and Marines will continue using the current fragmented and inaccurate method of accessing multiple, disparate systems for the nontactical information they need to accomplish their mission.

2.4. 3D Virtual Interface Requirements To optimize the use of the planned shipboard and shore-based IPDE, a new approach to developing and fielding a common desktop interface had to be developed. The interface must possess the capability, using a configurable Web portal design, to provide one integrated interface for all the shipboard nontactical applications. In addition, the interface must be designed for deployment based on task- or rolebased functions. For example, a sailor who has maintenance responsibility for specific equipment and components requires a system that provides a quick and efficient means to search and view accurate data using a user login.

3. Functionality This section outlines the functionality available to the user in myShipVI.

3.1. Ship Model Upon entering myShipVI, the user views the ship from a distance. Bitmaps are used for the sky and water to enhance the realism. Other bitmaps could be substituted as required. The 3D virtual ship model is geometrically accurate, having been extracted from the 3D CAD models used to design the ship. Using a semi-automated translation process, the individual CAD models are automatically converted into a light polygonal representation and then manually thinned as necessary. The resulting polygonal objects can also receive bitmaps to increase realism (see Figure 1).

Once the data is obtained from the IPDE system and other candidate shipboard systems, e.g. NTCSS, it can be integrated in the context of the request. The resulting information should be downloadable to the sailor’s laptop or wireless device of choice for mobility and readiness. In addition, if the source data is to be used in the maintenance of a ship’s equipment, the data must be reliable and configuration-managed.

3.2. User Interface / Navigation The myShipVI user interface was designed to give the user multiple alternative methods to locate the compartment they want to become familiar with, select a piece of equipment or component, and retrieve data (see Figure 2 on the following page). The user can navigate with a tree view located in the left hand user access area, go directly to a specific compartment using the ribbon bar, or graphically navigate using an overlay method to drill down by “progressive disclosure” to a specific deck, compartment, system, or component.

The primary objective of the initial 3D virtual interface was to make the shipboard IPDE more accessible, intuitive, functional, and easier to use for the sailor and Marine. Introducing another new system to sailors was going to be very difficult at best, so the idea of a 3D interface with FPP, similar to some computer games, as an interface for shipboard IPDE was a concept that received excellent preliminary reviews by logisticians and sailors alike. Most sailors are in their early twenties, and have grown up as part of the “Nintendo generation.” This statistic became a natural driver for the development of myShipVI.

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jump to the specific compartment in the 3D model (if the 3D model is toggled). A right mouse click on the compartment shows a list of functionally significant equipment in the compartment. Selecting a piece of equipment jumps the user to a location just in front of the equipment. Tool tips aiding the user in their navigation appear for both the decks and compartments.

Ribbon Bar Tree View

Compartment Key-in

Info Pane: Information and Search Results

Figure 2: myShipVI initial view and user interface elements

The tree view is a logical breakdown of the ship from ship/deck/compartment/part structure. Each functionally significant piece of equipment, significant in the operational and logistical sense, is selectable for retrieving pertinent data. Extended Structural Work Breakdown Structure (ESWBS) numbers and Record Identification Numbers (RIN) in the CDMD-OA and NTCSS typically track functionally significant equipment in the Navy throughout its life cycle. Functionally significant equipment typically has associated documentation and data, which are accessible through these identifiers. Equipment and components that are not functionally significant are visible in the model, but not included in the product tree (tree view). If the same catalog part occurs more than once in a compartment, the reoccurrences are grouped by part number for convenience.

Figure 3: Navigation via the 2D overlay

All three of these methods allow the user to quickly and easily access any part of the ship and retrieve information.

3.3. Walkthrough Model Once in a compartment, all equipment and components are visible as the user walks around. Each functionally significant part is visible and selectable for retrieving pertinent data. Users navigate thru myShipVI by way of the mouse and arrow keys, and can also accelerate relative speed by utilizing the shift key in conjunction with the arrow keys. Certain combinations of keys also allow the user to move vertically thru the model, create a “bird’s eye” view, and lock in a specific height as appropriate. For applications not limited by ship-specific standard equipment, the addition of a joystick will aid the navigation process.

The Info Pane at the bottom of the interface gives the user feedback on where they are and what has been selected last. It is also used to display data about the selected component and allows the user to obtain further details. The user may also key in a compartment number in the upper right hand corner of the ribbon bar and jump directly to the specified compartment. The 2D overlay, shown in Figure 3, allows the user to select a deck from the profile of the ship. (For convenience, the 3D model has been toggled off in Figure 3.) Once a deck is selected, the selected deck plan appears below the ship profile. The user can then select a compartment on the deck plan and

3.4. Controlling the Display Users have significant control over the display by utilizing the selective display capabilities of myShipVI. The display options are illustrated in Figure 4 below. Users can selectively hide or make transparent

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Intergraph Solutions Group White Paper classes of objects including: structure, ship plating, piping, HVAC, wireways, and equipment. In addition, a user may make a single piece of equipment transparent with a mouse click. This feature allows users to see behind objects that otherwise are hidden to the user.

3.5. Accessing Data Users access data and information in myShipVI by “selecting” an object through a double click. The Info Pane displays data about the selected equipment and provides links to numerous types of data that are accessible through the Intergraph Interoperability Framework™ (myShipI/F). Figure 6 illustrates this by displaying a reference to the wiring diagram.

Figure 4: myShipVI display options

For example, if you need to see how a backup structure is installed, you could make the parent plate system transparent and view the backup structure as attached to the plate. In another example, you could trace a piping system throughout the ship by hiding all other type objects and just viewing and navigating along the piping system. This is illustrated in Figure 5 where the HVAC has been hidden and the ship is transparent.

Figure 6: myShipVI with document record visible

The user retrieves the document by clicking on the hyperlink at the bottom of the record. Data types include drawings, documents, diagrams, simulations, technical manuals, operating instructions, and sequencing. Data and documents from multiple sources are accessed through myShipI/F, which also integrates the resultant data. myShipI/F always accesses the currently available data, therefore, the user always sees the latest updates to data and documents. myShipI/F also provides users with the ability to retrieve data and automatically feed other processes. For example, sailors are required to file a Ship’s Maintenance Action Form (OPNAV 4790/2K) when a piece of equipment requires maintenance. myShipI/F retrieves data from multiple sources using individual adapters and automatically populates the form with configuration-controlled data, freeing users from re-entering the data. This not only saves time, but also reduces errors that result from data entry and improves the quality of the submitted information.

Figure 5: myShipVI with selective display

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through myShipI/F, which integrates the resultant data. Access to these sources is based upon common identifiers such as part number, equipment number, hierarchical structure code (HSC), RIN, and nomenclature.

4. Implementation This section outlines the implementation of myShipVI. It is implemented using core software, Virtual Interface™ (myVI™) and Interoperability Framework (myI/F™), which has widespread applicability to many different domains, including ships, buildings, and airframes.

4.2. Interoperability Framework The Interoperability Framework is intended to provide user and application clients, such as myShipVI, a single point of access to integrated data from multiple data and information systems and repositories. It provides a scalable, extensible architecture in which applications interoperate using a common conceptual data schema.

4.1. Architecture The Intergraph family of 3D virtual interface products, myVI, is built on a real-time graphic-rendering engine to leverage the functionality and performance available through this technology. The rendering engine utilizes texture-mapped polygons for performance.

The Interoperability Framework accesses all data resources through adapters. Each data resource requires a dedicated adapter to translate data and commands between the Interoperability Framework and the application. The adapter communicates with the data resource, translating the system request into commands that the resource understands and uses to retrieve requested data. The business logic then combines all data received from the affected resource systems so that the client’s view of the data resources is a single, integrated set of information. This nonintrusive approach builds upon the data and functionality of existing systems without attempting to replace or tightly integrate them.

Although Non-Uniform Rational B-spline (NURB) surface geometry is well suited for design in a CAD system, tessellated polygonal surface geometry is typically used by gaming and simulation applications where file size, rendering speed, shading, and bitmap use are important. 3D CAD models are generally developed with manufacturing in mind, and the design of parts is often too detailed for the purpose of a real-time walkthrough engine. For example, a workstation in the CAD environment would have the gross outer shape of the equipment, but in the 3D virtual interface environment it can be reduced to very few polygon patches. With the addition of a bitmap picture of the screen and keyboard, the workstation becomes very realistic.

The Interoperability Framework exposes legacy systems as Web applications and provides an integrated view of data from multiple systems using a Web browser. It is designed to be a scalable architecture, which can be adapted and configured to support a wide range of interoperability solutions at the ship, depot, and NAVSEA level.

Each 3D virtual interface is implemented as a thick Web application. Server-side processing is used to access ship models, data, and documents. However, the graphic engine core requires client-side processing for rendering and event processing. The 3D virtual interface application and rendering engine are implemented as Microsoft ActiveX® controls, which must be loaded and registered on the client. All data resides on the server and is downloaded only as required. Users access server data through JavaServer Pages™ (JSP) and servlets. This ensures security, since once the ActiveX control is loaded from a trusted site, the 3D virtual interface acts like any other Web application.

The Interoperability Framework core software is generic and can be used in many different domains. However, the Interoperability Framework for ships, myShipI/F, uses a data model for ships, based on the Integrated Shipbuilding Environment Product Data Management (ISE PDM) schema, which was derived from the STEP Shipbuilding schemas6.

4.3. Graphic Rendering Engine

myShipVI stores selected static data about the ship – decks, compartments, and the compartment equipment list. It can also access data from other sources

The Intergraph family of 3D virtual interfaces is built on 3DLinX, a real-time graphic rendering

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Intergraph Solutions Group White Paper engine and development tool from Global Majic1. This rendering engine is designed for use with commercial off-the-shelf PCs running Microsoft Windows®. Intergraph selected the Global Majic graphic rendering engine because of its application programming interface (API), cost, product scalability, and good past performance ratings.

2. Extract the geometry and attributes from the CAD model files. A special translator was developed to output geometry to Wavefront’s OBJ data format and output text to an extensible markup language (XML) data format. The translator creates separate OBJ files for HVAC, raceway, beams, and plates, as well as individual files for unique equipment. The translator creates an XML file that contains attributes, position, and orientation for each extracted entity.

3DLinX utilizes OpenGL graphics acceleration and supports the importing of several graphics file formats – Wavefront OBJ, OpenFlight, 3D Studio, and Centric DWB. The optimizing rendering code includes support for texture, transparency, lighting, and perspective. The development tool-kit is based on component object model (COM) and ActiveX and supports the use of objects that have properties, methods, and events. It also supports a 2D overlay and collision detection. Finally, the graphic-rendering engine architecture is design-ed for extensibility to incorporate new primitives, user interface objects, controllers, drivers, file formats, and new effects.

3. Convert each OBJ file from NURB surface CAD graphics to lightweight tessellated surfaces, adding color and texture for realism. The Patch Editor tool reads the OBJ format files and massages the data to make it usable in a walkthrough environment. This tool allows the user to thin and convert these B-spline geometries to tessellated models, making them very lightweight and textured for a more realistic presentation.

4.4. myShipVI Application The implementation of the myShipVI application required the development of an ActiveX control to extend 3DLinX to support ship-specific functionality, including the graphical user interface (GUI), event handlers, and code that handles specific actions. The GUI code includes support for the product tree, Info Pane, and ribbon bar. The myShipVI application must manage mouse and keyboard events as well as perform actions on selected equipment.

The output of this tool is usable part files and assemblies (units or compartments) that will be used in the Intergraph 3D virtual interface. This tool also allows the user to color the geometry and perform simple texture mapping.

The following process was developed to create 3D virtual interface graphic files by extracting attributes and graphics from Integrated Ship Design & Production (ISDP) design files. The result of this process is a 3D ship model and a reusable library of equipment and components.

Special enhancements were added to the Patch Editor to help automate the thinning of objects with large polygon counts, such as HVAC and beams. Individual objects may, at the modeler’s discretion, be passed through to the LightWave 3D® tool for more realistic texturing. This includes cleaning up the geometry, texturing, and smoothing corners. LightWave 3D exported objects must be passed back through the Patch Editor for tessellation. The outputs of this step are tessellated entity files that may be in OBJ or LightWave Object (LWO) format.

1. Select the CAD model files required for the scene. Typically, multiple CAD files are accessed through an assembly file structure. In the case of LPD 17, where the 3D design was released by unit, this would be a unit assembly file.

4. Populate the database with attributes and locations for piping geometry and equipment. A tool (Dynamic Populate) was developed to read the XML data and populate a database to store attributes and locations for piping geometry and equipment. The tables

4.5. Creating 3D Interface Graphics from CAD Files

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throughout the ship. However, the size of the data associated with a ship, both graphics and static data, cannot be held in memory. Hence, myShipVI must adopt a strategy to load/unload models and product tree data as a user moves throughout the ship. The result must be minimal waiting time for the user as the interface loads new graphics and product trees. In general, this implies minimizing data processed on the client. For example, it was discovered that direct updates to Microsoft’s XML product tree were consuming all available CPU time, resulting in very slow response.

in this database associate identifiers with functionally significant items so queries into the middleware can return documents and data to this application. 5. Populate the 3D model. The Dynamic Populate tool reads the database created in Step 4. A directory containing the tessellated entity files developed in Step 5 creates the 3DLinX-formatted files containing the data for the 3D world (.3xw, .3xe, .3xs files). 6. Place newly generated files on the 3D virtual interface server and update the database with model file names (.3xe, .3xs files). Entry points must also be assigned to each compartment.

5.2. Automated Conversion of CAD Graphics One of the primary technical challenges faced was the development of an automated process to extract graphics and attributes from ISDP CAD models. Due to the size of the data associated with a ship, this process must be efficient. Intergraph has discovered three key automation improvements that have greatly improved translation efficiency.

The methods, processes, and programming tools developed to support the 3D virtual interface can also be used in the event that the master model was from a different 3D CAD modeling tool, such as CATIA or TRIBON. This only requires the development of a translator (Step 2) for that CAD system.

1. Automatic thinning The algorithms for the tessellation of NURB surface geometry often generate heavy models, i.e. models that incorporate many unnecessary polygons. Therefore, the models must be thinned, or extra polygons removed. Initially, users manually thinned each model. However, we noted that not all equipment models were excessively large. Currently, users monitor the file size of all tessellated models, and only manually thin large files or heavily used equipment.

4.6. Creating 3D Interface Graphics for Legacy Ships without CAD Models Creating static models of the ship, its compartments, and access layouts can also be accomplished from 2D drawings or photogrammetry if no 3D master model exists. End users create the 2D overlay from the inboard profile and deck arrangements. They then import equipment in each compartment from existing compartment lists. The compartment on the 2D overlay is linked to a compartment image with hot spots for key equipment. Note that this approach can be used with an incremental modeling strategy.

2. Surface Processing Users apply bitmaps and colors to only one side of a surface in the tessellated model. Initially, users spent considerable time and effort manipulating surfaces and surface normals to ensure proper representations. Later, automatically generating doublesided surfaces and coloring both sides optimized this process. This significantly reduced the time required to process equipment, at the cost of a slight increase in the model size.

5. Technical Challenges The implementation of the myShipVI has presented a number of technical challenges. This section describes the primary technical challenges experienced.

5.1. Performance Performance is vital to the success of a 3D virtual interface. The user must be able to walk smoothly

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orientation of equipment may vary in the original CAD model. Television monitors modeled as rectangular boxes may be placed in several orientations that will not become obvious until bit-maps are attached to specific faces in the tessellated model.

3. Automated CAD model updates Once users convert the equipment to a tessellated model, the position and orientation can be automatically updated from the CAD model. A prototype tool has been built to extract the new positions, update the database, and rebuild the world file. This applies to equipment and piping only.

6. Summary Intergraph has developed a general-purpose, Webbased 3D virtual interface for ship data, called myShipVI. It is based on a first person perspective, which runs on off-the-shelf hardware and software, and was built on a graphic-rendering engine designed to support simulation and gaming. myShipVI provides the user with a virtual tour of the ship, while providing access to the latest equipment and ship data from a variety of sources.

5.3. Level of Detail The level of detail required for a walkthrough may be greater than what is modeled in the CAD file. This is manifested in two ways: 1. Minimal CAD detail A piece of equipment may be modeled with minimal detail in the CAD system since the CAD user is concerned primarily with size, shape, and connectivity to electrical, HVAC, and piping systems. In general, bitmaps can be added to a piece of equipment to add realism and show aspects not included in a CAD model. For example, bitmaps representing the screen and keyboard can be added to a workstation CAD model.

myShipVI is different from traditional modeling and simulation tools in that it is optimized to execute on a standard desktop or laptop. myShipVI runs well on a minimum of a single 700 MHz processor, and 512 MB of RAM, and will be available to sailors and Marines through SWAN in more than several hundred locations throughout the ship. The solutions provided with the Intergraph 3D virtual interface and I/F have widespread applicability. The core software can be quickly adapted to a new data model, whether it be another ship class or any other structure. The software will work for other ships, buildings, airframes, etc. Once the initial framework is in place, it can easily be modified to work with any structure that has decks or levels, compartments or rooms, and equipment or furniture, or any combination of the above.

2. Missing components Some components are not considered significant in the CAD world and may not be modeled, e.g. raised floor coverings or furniture. Additional objects can be modeled in LightWave 3D or similar tools and then added to the model to represent these components.

In addition, myShipVI has been used to successfully integrate models that originated in different 3D CAD modeling tools. The tool can be used with other CAD systems such as CATIA or IntelliShip® by utilizing the same process and modifying the CAD specific translator. Currently, pilot programs are also planned to utilize both photogrammetry and laser technology to capture and convert as-is geometry for existing structures that may not have been designed and constructed using a 3D CAD model.

5.4. Model Validation The translation process has not yet been fully perfected. As a result, the tessellated model must be validated against the original CAD model. Currently, examining the equipment placement and connectivity of systems is a manual inspection process. The intent is to automate portions of this process for both initial model creation and updates. Errors are often a result of the translation process, such as equipment with the wrong orientation. However, the translation process also uncovers errors in the original CAD model. For example, the

For more information about this topic, please email Ted L. Briggs at [email protected], Steve

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A 3D Interface to Access Ship Data

Intergraph Solutions Group White Paper J. Baum at [email protected], or Tammi M. Thomas at [email protected]. Intergraph, the Intergraph logo, myShipVI, Interoperability Framework, Virtual Interface, myVI, myI/F, and IntelliShip are registered trademarks of Intergraph Corporation. Microsoft, Windows, Windows NT, and ActiveX are registered trademarks of Microsoft Corporation. Other products and brand names are trademarks of their respective owners. Reproduction of this publication in any form without prior written permission is forbidden. The information contained herein is based on Intergraph’s opinion and is believed to be reliable. Intergraph disclaims all warranties as to the accuracy, completeness, or adequacy of such information. Intergraph shall have no liability for errors, omissions, or inadequacies in the information contained herein or for interpretations thereof. The opinions expressed herein are subject to change without notice. Copyright 2004 Intergraph Corporation, Huntsville, AL 35894-0001. All rights reserved. 20033047B 8/04

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A 3D Interface to Access Ship Data

Intergraph Solutions Group White Paper

NOMENCLATURE OPNAV 4790/2K 3DLinX ACIS ActiveX API CAD CATIA CDMD-OA COM ESWBS FPP FSI GUI HSC HVAC I/F IDE IGES IGRIP IntelliShip IPDE ISDP

ISE ISO JSP LightWave 3D LPD LWO MHz myI/F myShipVI myShipI/F myVI NAPA NAVSEA NSRP

Deferred repair documented on OPNAV form 4790/2K A real-time graphic-rendering engine and development tool from Global Majic. Supports import of OBJ and Open Flight file formats. 3D solid modeler and graphics file format from Spatial Microsoft’s COM component designed to provide integration of controls into Web browsers. Application programming interface Computer-aided design Computer-Aided Three Dimensional Interactive Application. CAD system developed by Dassault Systems. Configuration Data Manager Database - Open Architecture. Shore-based configuration control system storing SCLSI data. Component object model. Modular programming paradigm developed by Microsoft. Extended Structural Work Breakdown Structure. Navy-assigned SCLSI data element with five characters. First-person perspective Functionally significant item Graphical user interface Hierarchical structure code. SCLSI data element consisting of a 12-character code assigned by shipbuilder. The first five characters are an ESWBS number. Heating, ventilation, and air-conditioning Interoperability Framework Integrated data environment Initial Graphics Exchange Specification. Defines a neutral file format for model data and 3D graphics. A modeling and simulation application from Delmia Next-generation shipbuilding CAD system developed by Intergraph Integrated product data environment Integrated Ship Design & Production, an Intergraph shipbuilding CAD system with the ability to create a ship design that speeds product development from conception to market delivery Integrated Shipbuilding Environment Project under the NSRP ASE Program International Organization for Standardization JavaServer Pages, owned by Sun Microsystems 3D polygon modeling tool from Newtek Landing platform dock Light Wave Object. 3D graphics file format from LightWave 3D Megahertz Interoperability Framework. Intergraph interoperability product for ships, airframes, or buildings. Ship Virtual Interface. Intergraph 3D virtual interface product for ships. Intergraph Interoperability Framework product for ships Virtual Interface. A family of Intergraph 3D virtual interface products for ships, airframes, or buildings. Naval architectural package. A shipbuilding CAD system. U.S. Naval Seas Systems Command National Shipbuilding Research Program

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A 3D Interface to Access Ship Data

Intergraph Solutions Group White Paper NTCSS

Naval Tactical Command Support System. Shipboard configuration-control system storing SCLSI data. NURB Non-Uniform Rational B-spline OpenFlight 3D graphics data format from MultiGen OpenGL Open graphics library. An open source 2D and 3D graphics API. OBJ A 3D graphics file format supporting texture mapping from Alias/Wavefront ONYX High-performance workstation made by Silicon Graphics PDM Product data management RAM Random access memory. Typically used to denote the size of physical memory in a computer. RIN Record identification number. SCLSI data element used to uniquely identify equipment or component. SCLSI Ship configuration and logistics support information STEP Standard for the Exchange of Product Model Data (ISO 10303). Defines a neutral file format for product model data and 3D graphics. SWAN Ship wide area network. Network aboard LPD 17. Tessellated Surface represented by a covering of polygons, typically triangles TRIBON A shipbuilding CAD system marketed by Tribon Solutions TWR Torpedo Weapons Retriever. A 120-foot ship built in 1985 whose technical data was released by Navy for public use. Used as the source of NSRP ISE test data. Virtual Interface An interactive, graphical interface supporting a first person perspective in which a user can virtually navigate throughout a ship, airframe, or building and selectively retrieve information about equipment and components. VRML Virtual Reality Modeling Language. An open-source format used to render 3D graphics in Web applications. XML Extensible Mark-up Language

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REFERENCES 1. Global Majic, 3D Components Overview, www.globalmajic.com/3dover.asp. 2. L. Benthall, T. Briggs, B. Downie, B. Gischner, B. Kassel, R. Wood., STEP for Shipbuilding: A Solution for Product Model Data Exchange, Proceedings of 2002 Ship Production Symposium. 3. TWR model data, http://rabecs.dt.navy.mil. 4. J. Matti and T. K. Lauri, Saving Time and Money with Integrated 3D Product Modeling and Life Cycle Management Tool, Proceedings of the 11th International Conference on Computer Applications in Shipbuilding, Malmo, Sweden, 2002, pp 501-513. 5. S. Baum, J. Boudreaux, N. Bourassa, J. Jenkins, An Information Technology Blueprint for the Twentyfirst Century Amphibious Warship, Proceedings of The Society of Naval Architects and Marine Engineers, 1999. 6. T. Briggs and T. Rando, XML Schemas for Shipbuilding, Proceedings of 11th International Conference on Computer Applications in Shipbuilding, Malmo Sweden, September 2002.

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Headquarters Solutions Group Intergraph Corporation 170 Graphics Drive Madison, AL 35758 800-747-2232 For more information about Intergraph Solutions Group, please visit our Web site at http://solutions.intergraph.com