Visual Area Modeling

Area Database Modeling

The Modeling department at PMI utilizes a powerful Visual Modeling Tool intended for the production and updating of integrated databases for simulators of the Navi-Trainer ver. 4000 family and higher. It is also designed for the planning of construction works at ports, research of depth models, and the modeling of navigational situations.

Modeling Tools

The databases generated by PMI's Modeling Department include magnetic deviations, racons, lighthouses, buoys with topmarks, and a set of templates to create models and objects. The Modeling Team incorporates an editor for creating and modifying 3-D models of coastal objects, plus visual and motion models of ships. 

The generated scene can be

supplemented with 3-D models (prototypes) from the Object Library or be built utilizing AutoCAD and textured using photographs.  Illumination effects can be set (such as any time of the day and night or weather conditions).

PMI's Modeling Department customizes the visual scenarios based on the clients objectives.  Visual scenarios range from Low to High detail as described and illustrated below.

Levels of Detail

Quality of an exercise area workout is usually described in terms of Levels Of Detail. The Implementation of the things listed below defines these Levels:

1. Piers for Mooring Operations

2. Aids to Navigation

3. Landmarks

4. Cultural Features

5. Landscapes

High Level (Precise for Harbor Simulation)

A high level of detail is required to facilitate close in maneuvering and berthing operations. Training scenarios will provide visual details and depth perception to enable berthing maneuvers to be conducted with high realism without the use of radar ranging.

Jetties designated for berthing are displayed with the maximum detail possible without considerable degradation of the refresh rate of the visual system. Usually, the refresh rate in “precise detail” areas is 40-60% less than in low scene content areas such as “open sea”. The depth model is developed using the most detailed scale electronic chart that is available in the TRANSAS collection for the particular area.  Corp of Engineer or other data can be imported in to the visual model to ensure exact bottom depths, contours, etc.

Soundings are developed for a full range of depths and heights, including drying areas, which are submerged in high

 tidal conditions.  Aids to navigation are given special attention during visual scene development and are created to accurately represent actual size, shape and color characteristics in accordance with light list publications and supporting photographs.

Landmarks are developed with accurate and realistic size and shape.  The landscape close to navigable waters is developed to achieve the highest level of accuracy, recognizable appearance and depth perception. Cultural features, which are not specified as landmarks, are developed to a recognizable scale and with texture characteristics. These features will be visually correct when viewed from any point within the “precise detail” area.  Jetties and wharves, not designated for berthing, are correctly positioned and appropriately detailed for the level of navigational function they serve.

Medium Level (Used for Navigational Route Simulation)

This level of detail provided is sufficient to facilitate training in navigation practices used in transit passages. There is sufficient detail to enable the trainee to accurately determine the ship's position by the use of Aids to navigation and landmarks.

The depth model is developed from the most detailed electronic chart available for the specific area.  Soundings are developed in the database for operation in a moderate range of depths (to the 5-meter contour). Coastal depths (from 5m to coastline) are developed approximately.

Aids to navigation are given special attention during visual scene development and are created to accurately

represent actual size, shape and color characteristics in accordance with light list publications and supporting photographs.  Landmarks are developed with accurate and realistic size and shape.

Landscape close to navigable water is developed to achieve accurate and recognizable appearance.
Cultural features that are not specified as a landmark are developed approximately but as realistically as possible. These features are seen to be most realistic when viewed only from specified navigation routes.
Jetties and wharves are schematically represented or omitted.

Low Level (Used for Coastal Navigation)

Simulation training at this level does not normally rely upon visual navigation alone, and the distance off shore will usually necessitate determining the position of the ship using a combination of visual information, radar ranging and charted data.

Navigational operations are generally conducted outside ranges of three to five nautical miles from the shore and sailing routes do not depend on recommended tracks.

Aids to navigation are given special attention during visual scene development and are created to accurately represent actual size, shape and color characteristics in accordance with light list publications and supporting photographs.  Landmarks are developed with accurate and realistic size and shape.

Landscape is developed schematically with representative color and contour to define the coastline on the skyline.
Jetties and wharves are omitted.

Illustrations of pier “enhancing” in “Los Angeles” exercise area