Water body encoding for a vision system

Abstract

The present invention is titled "Water Body Coding for a Vision System". The present invention provides a technically improved vision system and method for providing enhanced water coding. The vision system receives terrain data from a terrain database and aircraft state data from a navigation system. The vision system commands a display system to display a map image reflecting a view from the current position of the platform. The vision system processes the terrain data and the aircraft state data to identify water body features, determine the distance between the platform and the water body features, and determine a texture representation of the water body features. The texture representation includes symbols and associated symbol patterns. The vision system commands the display system to overlay the water body features on the map image with the texture representation.

Description

Technical Field

[0001] The present invention generally relates to vision systems for mobile platforms and, more particularly, to encoding of water bodies for vision systems. Background Art

[0002] Generally, vision systems include head-down displays and head-up displays. In a synthetic vision system (SVS) head-down display (HDD), land, water, and sky are represented by significantly different colors to facilitate pilot differentiation and situational awareness. In an enhanced vision system, infrared images represent the thermal characteristics of the forward field of view, and water and land areas may or may not be distinguishable via perceived intensity. In a combined vision system (CVS) HDD, SVS images and EVS images are combined into one image. In a CVS HDD image, the EVS video insert portion may be colored by the background land / water / sky color of the SVS image.

[0003] Compared to HDDs, head-mounted displays (HMDs), near-eye displays (NTEs), and head-up displays (HUDs) must be usable under a wide range of ambient light conditions, and the displays are typically monochromatic. Thus, particularly under bright ambient conditions, using intensity to differentiate water, land, and sky may be ineffective on a HUD. Displaying SVS images and / or CVS images on a typical monochromatic HUD and using color intensity to differentiate water, land, and sky may be particularly ineffective.

[0004] Accordingly, there is a need for improved vision systems and methods. Specifically, it is desirable to provide enhanced encoding of water bodies and systems and methods that support technical improvements for various vision systems. Additionally, other desired features and characteristics of the present disclosure will become apparent in light of the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and the background art. Summary of the Invention

[0005] This Summary of the Invention is provided to introduce a selection of concepts in a simplified form that are further described in the Detailed Description. This Summary of the Invention is not intended to identify key or essential features of the claimed subject matter nor is it intended to be used to assist in determining the scope of the claimed subject matter.

[0006] A method for a vision system in a platform is provided. The method includes: at a control module, receiving terrain data from a terrain database; receiving vehicle state data from a navigation system; displaying an image on a display system that reflects a view from the current location of the platform; processing the terrain data and the vehicle state data to (i) identify water body features and (ii) determine a texture representation of the water body features; and texturing the water body features by overlaying the texture representation on the water body features in the image.

[0007] There is also provided a vision system, the vision system including: a navigation system; a display system; a terrain database; and a control module operatively coupled to the navigation system, the display system, and the terrain database, the control module being configured to: receive terrain data from the terrain database; receive aircraft state data from the navigation system; display on the display system a map image reflecting a view from the current position of the platform; process the terrain data and the aircraft state data to (i) identify water body features, and (ii) determine a texture representation of the water body features; and texture the water body features by overlaying the texture representation on the water body features on the map image.

[0008] There is provided a control module for a combined vision system (CVS) on an aircraft having a navigation system. The control module includes: a memory including terrain data; and a processor operatively coupled to the memory and configured to process the terrain data and aircraft state data to: generate a display command for causing the display system to generate a map image reflecting a view from the current position of the aircraft; identify water body features; and determine a texture representation of the water body features.

[0009] Additionally, other desirable features and characteristics of the system and method will become apparent in light of the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing background. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be described below in conjunction with the following drawings, in which like numerals represent like elements, and

[0011] Figure 1 is a block diagram of an enhanced vision system according to an exemplary embodiment;

[0012] Figure 2 is according to an exemplary embodiment Figure 1 of the control module block diagram;

[0013] Figure 3 is a schematic diagram showing water body coding in a combined vision system (CVS) according to an exemplary embodiment;

[0014] Figure 4 is a remote image from a head-up display (HUD) according to an exemplary embodiment;

[0015] Figure 5 is a head-up display (HUD) image showing a natural landmark according to an exemplary embodiment;

[0016] Figure 6is a short-range image from a head-up display (HUD) according to an exemplary embodiment; and

[0017] Figure 7 is a flowchart of a method for encoding a water body according to an exemplary embodiment. DETAILED DESCRIPTION

[0018] The following detailed description is merely exemplary in nature and is not intended to limit the embodiments of the subject matter or the application and use of such embodiments. As used herein, the term "exemplary" means "serving as an example, instance, or illustration." Thus, any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or more advantageous than other embodiments. All embodiments described herein are exemplary embodiments provided to enable those skilled in the art to make or use the invention and not to limit the scope of the invention defined by the claims. Additionally, there is no intention to be bound by any theory presented in the foregoing background or the following detailed description.

[0019] As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic, and / or processor device, individually or in any combination, including but not limited to: application specific integrated circuits (ASICs), electronic circuits, processors (shared, dedicated, or grouped), and memories that execute one or more software or firmware programs, combinational logic circuits, and / or other suitable components that provide the described functionality. The provided systems and methods may take the form of a control module ( Figure 1 , 104) and may be separate from or integrated into a pre-existing mobile platform management system, avionics system, or aircraft flight management system (FMS).

[0020] Exemplary embodiments of the disclosed vision system 102 and control module ( Figure 1 , 104) effectively texture water body features by determining a texture representation of the water body features and commanding a display system ( Figure 1 , 30) to overlay a map image with the texture representation. Selected symbols and symbol patterns may be related to the distance between the aircraft 100 and the water body features; and, the selected symbols and symbol patterns may change as the aircraft 100 crosses one or more range boundaries of the distance from the water body features. Through the texturing of the water body features described herein and some additional features described below, the control module 104 provides a technical improvement over conventional vision systems that require excessive effort to distinguish water and land, particularly in monochromatic applications and under a range of ambient lighting conditions. These features and additional functions are described in more detail below.

[0021] Now turning to Figure 1, in the provided example, platform 100 is an aircraft and may be referred to as aircraft 100. In the described embodiments, control module 104 is generally implemented to command a technology-enhanced vision system 102 (also referred to as the "water body encoding system" 102 and "system" 102) within aircraft 100. In the described embodiments, control module 104 and vision system 102 are within aircraft 100; however, the concepts presented herein may be deployed in various mobile platforms, spacecraft, etc. Thus, in various embodiments, control module 104 may reside elsewhere and / or augment a portion of a large avionics management system or platform management system. Additionally, it should be understood that system 102 may be different from Figure 1 the embodiments depicted in 1. For example, aspects of user input device 34, display system 30, and graphics system 32 may form a control display unit (CDU) for commanding and controlling FMS106.

[0022] Control module 104 may be operatively coupled to: a flight management system (FMS) 106, a user interface 108 (which may include one or more of display system 30, graphics system 32, and user input device 34), an on-board sensor system 110, and a terrain database 114. The operation of these functional blocks is described in more detail below.

[0023] The depicted FMS 106 provides a flight plan for an anticipated landing and a destination runway. As depicted, FMS 106 is a functional block that includes a navigation system 20 and a navigation database 22, and thus may provide position determination data retrieved from sensor components within navigation system 20. Navigation system 20 includes sensors for determining the instantaneous current position of aircraft 100. The instantaneous current position of platform or aircraft 100 may be referred to as aircraft state data and / or position determination data, and includes the current latitude, longitude, heading, and current altitude (or above ground level) of aircraft 100. In various embodiments, the means for determining the current or instantaneous aircraft state data of aircraft 100 may be implemented as a global positioning system (GPS), an inertial reference system (IRS), or a radio-based navigation system (e.g., VHF omnidirectional radio range (VOR) or long range navigation (LORAN)), and may include one or more navigation radios or other sensors appropriately configured to support the operation of navigation system 20, as recognized in the art. Under the guidance of program 162 (see Figure 2 ), control module 104 may process navigation data to determine the instantaneous position of the aircraft relative to the flight plan and guide the aircraft in accordance with the flight plan. Control module 104 may also process the flight plan and position determination data to determine the current flight phase.

[0024] The navigation database 22 may include waypoint information, airport feature information, runway positions and location data, holding patterns, flight procedures, approach procedures, and various flight plans and distance measurement rules and parameters. The FMS 106 is configured to provide guidance to the flight crew, such as lateral navigation (LNAV) and vertical navigation (VNAV), based on processing aircraft state data using the information within the navigation database 22. As used herein, "navigation data" may include data and information from the navigation system 20 and / or the navigation database 22, such as, but not limited to, aircraft state data and current flight phase information.

[0025] The user interface 108 is coupled to the control module 104 and is cooperatively configured to allow a user (e.g., a pilot, co-pilot, or flight crew) to interact with the display system 30, the FMS 106, and / or other elements of the system 102 in a conventional manner. The user interface 108 includes one or more of the systems described below (the display system 30, the graphics system 32, and the user input device 34).

[0026] Generally, the display system 30 may include any device or equipment suitable for displaying (also referred to as rendering) flight information or other data associated with the operation of the aircraft in a user-viewable format. The display device may provide a three-dimensional or two-dimensional map image and may also provide synthetic vision imaging. Thus, the display device responds to the corresponding communication protocol in two dimensions or three dimensions and may support the overlay of text, alphanumeric information, or visual symbols on a given map image. Non-limiting examples of such display devices include cathode ray tube (CRT) displays and flat panel displays, such as LCD (liquid crystal display) and TFT (thin film transistor) displays. In fact, the display system 30 may be a primary flight display (PFD) system, a multifunction display (MFD), a panel-mounted head-down display (HDD), a head-up display (HUD), or a head-mounted display system (such as part of a "near-eye display" system or may include them. For the purposes of this embodiment, the focus will be on the head-up display (HUD).

[0027] The rendering of the display system 30 can be processed at least in part by the graphics system 32. The display method includes various types of computer-generated symbols, text, and graphical information, which are represented in an integrated multi-color or monochrome form, such as pitch, heading, flight path, airspeed, altitude, runway information, waypoints, targets, obstacles, terrain, and required navigation performance (RNP) data. In some embodiments, the graphics system 32 can be integrated within the control module 104; in other embodiments, the graphics system 32 can be integrated within the display system 30. Regardless of the integration status of these subsystems, in response to receiving a display command from the control module 104, the display system 30 displays, renders, or otherwise visually conveys one or more graphical representations or images associated with the operation of the aircraft 100, as described in more detail below. In various embodiments, the images displayed on the display system 30 can also be responsive to processed user input received via the user input device 34.

[0028] The user input device 34 can include any one or combination of various known user input devices, including but not limited to: a touch-sensitive screen; a cursor control device (CCD) (not shown), such as a mouse, trackball, or joystick; a keyboard; one or more buttons, switches, or knobs; a voice input system; and a gesture recognition system. Non-limiting examples of the use of the user input device 34 include: inputting the value of the stored variable 164, loading or updating instructions and applications 160, loading and updating programs 162, and loading and updating the content of the database 156, each of which is described in more detail below. Additionally, a pilot or crew member can input a flight plan, standard operating procedure (SOP), etc. via the user input device 34. In embodiments using a touch-sensitive screen, the user input device 34 can be integrated with the display device in the display system 30.

[0029] The airborne sensor system 110 includes a variety of different sensors, each of which is directed at sensing a corresponding different system of the aircraft 100 during flight. Non-limiting examples of the sensors include: wind direction and speed sensors, fuel level sensors, engine temperature sensors, humidity sensors, cabin sensors, and other system status sensors. In addition to sensing the aircraft 100 systems during flight, some airborne sensors are externally focused and provide environmental and terrain information. Thus, the real-time aircraft sensor data includes real-time local weather data and infrared sensing data in addition to the aircraft system data, as expected for an enhanced vision system (EVS).

[0030] The terrain database 114 includes environmental feature information related to the travel path that the aircraft 100 will take. Non-limiting examples of terrain data from the terrain database include size, shape, area, location (latitude, longitude, feet above sea level), and the boundaries between land, air, and water body features. The terrain data can be pre-loaded into the terrain database 114 and then selectively transferred to the memory 152 during the execution of an algorithm for texturing the water body features embodied in the program 162. In other embodiments, the terrain data is already included in the control module 104, such as in the database 156.

[0031] The control module 104 processes inputs from operatively coupled components and performs the functions of range determination 40 and texture determination 42. In combination Figure 2 The control module 104 and its functions are further described below.

[0032] The control module 104 includes an interface 154 that is communicatively coupled to the processor 150 and the memory 152 (via the bus 155), the database 156, and an optional storage disk 158. The processor 150 can include any type of processor or multiple processors, a single integrated circuit such as a microprocessor, or any suitable number of integrated circuit devices and / or circuit boards that work together by manipulating electrical signals representing data bits at memory locations in the system memory and other processing of the signals to perform the described operations, tasks, and functions.

[0033] Memory 152, navigation database 22, terrain database 114, database 156, and optional disk 158 store data bits and can be used by processor 150 as a storage device and a scratch pad. Memory locations for holding data bits are physical locations having specific electrical, magnetic, optical, or organic characteristics corresponding to the data bits. Memory 152 can be any type of suitable computer-readable storage medium. For example, memory 152 can include various types of dynamic random access memory (DRAM) (such as SDRAM), various types of static RAM (SRAM), and various types of non-volatile memory (PROM, EPROM, and flash memory). In some examples, memory 152 is located on and / or co-located with processor 150 on the same computer chip. In the depicted embodiment, memory 152 stores the above-mentioned instructions and application 160 together with one or more configurable variables in storage variable 164. Database 156 and disk 158 are computer-readable storage media in the form of any suitable type of storage device, including direct access storage devices such as hard disk drives, flash memory systems, floppy disk drives, and optical disk drives. Database 156 can include an airport database (including airport features) and a terrain database (including terrain features), parameters and instructions for runway detection and selection, and parameters and instructions for generating alerts as described herein. The combination of features in the airport database and the terrain database is referred to as map features. The information in database 156 and memory 152 can be organized and / or imported during the initialization step of the process (see Figure 7 Initialization 702) in an external source 130 or by programming via user input device 34.

[0034] Bus 155 is used to transfer programs, data, status, and other information or signals between various components of control module 104. Bus 155 can be any suitable physical or logical means for connecting computer systems and components. This includes but is not limited to direct hardwired connections, fiber optics, infrared, and wireless bus technologies.

[0035] Interface 154 enables communication within control module 104, can include one or more network interfaces for communicating with other systems or components, and can be implemented using any suitable methods and devices. For example, interface 154 enables communication from system drives and / or another computer system. In one embodiment, interface 154 obtains data directly from external data source 130. Interface 154 can also include one or more network interfaces for communicating with technicians, and / or one or more storage interfaces that support a direct connection to a storage device such as database 156.

[0036] During operation, the processor 150 loads and executes one or more programs, algorithms, and rules embodied as instructions and application programs 160 contained within the memory 152, and thus controls the control module 104 and the general operation of the system 102. When executing the processes described herein (such as Figure 7 method 700), the processor 150 specifically loads and executes the instructions and models contained within the novel program 162. Within the control module 104, the processor 150 and the memory 152 form a processing engine that performs processing activities, data conversions, and data translations that result in the functions of the control module 104, as described in more detail below. The control module 104 may perform its functions according to the steps of a method ( Figure 7 , method 700).

[0037] Additionally, the processor 150 is configured to, according to the program 162: process the received input (optionally, any combination of inputs from a group including: the FMS 106, the user interface 108, the on-board sensor system 110, the input / output (I / O) system 112, and the external source 130); reference any databases (such as the terrain database 114, the navigation database 22, and the database 156); and generate commands and commands to control the user interface 108 (specifically, the display system 30).

[0038] Generally, the control module 104 determines a texture representation of the water body feature and commands the display system 30 to overlay the texture representation on the synthetic vision system (SVS) map image. This is also referred to as "texturing the water". In Figure 3 , the thumbnail 300 represents this concept in a combined vision system (CVS) image having an SVS image covered by an EVS image 302. The SVS water boundary 304 is shown below the zero pitch reference line ZPRL 306. In the EVS image 302, the water boundary is 310. The texture representation for the water body feature includes symbols 308 that repeat within the water boundaries (304, 310) of the water body feature, throughout the water body feature. The water symbols 308 may optionally be positioned on top of the EVS image of the area within the water boundary. The repetition of the symbols 308 may follow a pre-arranged symbol pattern. The arrangement of the symbols 308 into a symbol pattern will be described in connection with Figures 4 - 6 .

[0039] The water body coding system 102 commands the display system 30 to render a map image that reflects the view from the current position of the vehicle. The top of the map image represents the feature farthest from the aircraft 100, while the bottom of the map image represents the feature closest to the aircraft 100. Now turning to Figure 4, The perspective view image (SVS image 400) represents the terrain and environment as seen looking forward from the platform in the direction of travel. At the top of the SVS image 400, the sky 456 extends downward to a boundary 452 where the sky 456 meets the water body feature 450, the land mass 402, and the land mass 404. As the aircraft 100 travels, the SVS image 400 is continuously updated to reflect the status data (positioning and location) of the aircraft 100. The boundary 452 is a virtual boundary, meaning it represents the farthest extent of the display view from the aircraft 100, rather than a real boundary between features defined in the terrain database 114. For the purposes of this discussion, the boundary shown on the map image is the boundary used to determine the water body feature for texturing. Thus, depending on the instantaneous positioning and location of the aircraft 100, a given boundary of the water body feature can be real or virtual.

[0040] The control module 104 determines the texture representation of the water body feature 450. The control module 104 generates a display command for causing the display system 30 to texture the water body feature 450. In response to the display command, the display system 30 textures the water body feature 450 by overlaying the water body feature with the texture representation on the map image (SVS image 400). The texture representation is selected to provide sufficient contrast around the water texture symbol such that when overlaid on the map image employing a shading technique, the texture representation remains visibly distinct and distinguishable. For example, the textured water body feature 450 can be readily introduced and rendered on the HUD CVS image.

[0041] In various embodiments, the texture representation includes symbols and associated symbol patterns. It should be understood that multiple symbols can be employed, and multiple symbol patterns can also be employed, and each symbol pattern can be selectively associated with one another. A given symbol pattern can include dimensions responsive to one or more of the following: (i) the dimensions of the water body feature 450, and (ii) the position of the aircraft 100 relative to the water body feature 450. Additionally, the symbol dimensions can be based on one or more of the following: (i) the symbol pattern dimensions, (ii) the dimensions of the water body feature 450, and (iii) the position of the aircraft 100 relative to the water body feature 450.

[0042] Continue Figure 4, the map image of the SVS image 400 depicts symbols 408 (plus signs or crosses) that repeat in a symbol pattern. The first symbol pattern is a grid of rows and columns, with each row separated from its adjacent row by a row space 414, and each column separated from its adjacent column by column spaces (column space 410 and column space 412). The symbols 408 are typically distributed in the first symbol pattern such that one symbol 408 occupies each intersection of a row and a column. In other words, the symbols 408 are separated from each other by the row space 414 and the column spaces (column space 410 and / or column space 412). In some texture representations, the symbol pattern has equal column spaces 410 and 412. In other texture representations, the column spaces 410 and 412 are not equal. In some embodiments, the columns are parallel to each other and perpendicular to the rows. As previously mentioned, multiple other symbol patterns are supported.

[0043] The distance between the aircraft and the water body feature 450 can be visually expressed using a texture representation. For example, in the map image SVS image 400, the column spaces 410 and 412 are wider at the bottom and narrower at the top to indicate the viewing angle or distance between the aircraft 100 and the water body feature. The distance between the aircraft and the water body feature 450 can also be visually expressed by changing the texture representation based on a predetermined configurable distance called a threshold range.

[0044] When a threshold range is employed, the control module 104 compares the range or distance between the aircraft 100 and the water body feature with the threshold range. The change from one side of the threshold range to the other is rendered in a visually distinguishable manner. For example, when the distance between the aircraft 100 and the water body feature 450 is less than or equal to the threshold range, one texture representation can be employed, and when the distance from the aircraft 100 to the water body feature 450 is greater than the threshold range, the texture representation can be modified or another texture representation can be employed. Any combination of the above symbols and symbol patterns can be selectively utilized in the texture representation based on the threshold range.

[0045] To demonstrate this concept, consider the texture representation overlaid on the Figure 4 map image as an example of a texture representation where the distance between the aircraft 100 and the water body feature 450 is less than or equal to the threshold range. Although the plus signs of the symbols 408 as shown are visually distinguishable, viewing the same water body feature from a greater distance may cause multiple symbols 408 to be crowded into a very small map image space, making them difficult to distinguish. When the aircraft 100 gets closer and closer to the ground to enhance ground closure perception cues, the control module 104 can employ an increase in texture density - for example, first you see a forest, then you see trees, and as you get closer, you see branches and then as you get even closer, you see leaves. Figure 4 and Figure 5For comparison, when the aircraft 100 is farther away, different texture representations are used.

[0046] In Figure 5 it has been determined that the distance between the aircraft 100 and the water feature 550 is greater than the threshold range. In Figure 5 the SVS image 500 shows a boundary 552 separating the water feature 550 from the sky 556. The land is represented by 502. Color intensity variations are used for the monochromatic map image of the SVS 500. In Figure 5 the texture representation utilized includes symbols 508 (dots), which are visually distinguishable from the plus signs of the symbols 408 and are more suitable for crowded map images. The symbols 508 are distributed in rows and columns on the water feature 550. In addition to using different symbols at greater distances, the column space 512 and the row space 514 can also be visually distinguishable (i.e., of different sizes) from the row space 414, the column space 410, and the column space 412.

[0047] Symbols and symbol patterns are also selected to be easily visually distinguishable from the symbols used to represent natural landmarks; Figure 6 depicts such an example. The SVS image 600 depicts a water feature 650, land 602, and sky 656. The symbols 608 are distributed throughout the water feature 650 and are separated from each other by the column space 610 and the row space 614. Symbols and symbol patterns for land features, such as a landing strip 660, are shown. As can be observed, the symbols 608 can be easily visually distinguished from the symbols for the landing strip 660 and other symbols (such as the symbol indicating the synthetic enhanced runway extension centerline).

[0048] As described above, the control module 104 can be used to implement the method 700, as shown in the flowchart of Figure 7 For illustrative purposes, the following description of the method 700 may refer to the elements described above in connection with Figure 1 and Figure 2 In fact, parts of the method 700 may be performed by different components of the system. It should be understood that the method 700 may include any number of additional or optional tasks, Figure 7 the tasks shown in Figure 7 need not be performed in the order shown, and the method 700 may be incorporated into a more comprehensive process or method with additional functions not described in detail herein. Additionally, one or more of the tasks shown in

[0049] The method begins, and at 702, control module 104 is initialized. As described above, initialization can include uploading or updating instructions and applications 160, programs 162, stored variables 164, and various look-up tables stored in database 156. Examples of parameters that can be stored in stored variable 164 include parameters used by instructions and applications 160 and programs 162 (e.g., predetermined configurable ranges, and values for scaling and adjusting the size of texture symbols and their layout in various symbol patterns). Stored variable 164 can also include various shape, size, and color rendering references for flight images, buttons, and displays used to solicit user input on a graphical user interface (GUI) such as that displayed on display system 30. Program 162 can also include additional instructions and rules for commanding any of the various specific display devices described in connection with display system 30.

[0050] At 704, vehicle state data is received. As described above, vehicle state data includes position determination data provided via navigation system 20; thus, vehicle state data includes the instantaneous, real-time location and position of vehicle 100. At 706, terrain data is received. The terrain data can be received from terrain database 114. In some embodiments, the terrain data has been copied into a memory (such as memory 152 or database 156) within control module 104. The terrain data includes the necessary boundary and feature information to distinguish the environment along the flight path of vehicle 100 (i.e., to distinguish land, water, and air). At 708, control module 104 commands display system 30 to render a map image that reflects a view from the current position of vehicle 100. It should be understood that the map image includes information about the terrain surrounding vehicle 100. Step 708 is continuously repeated such that the map image continuously reflects a view from the current position of the vehicle as vehicle 100 travels.

[0051] At 710, terrain data and vehicle state data are processed to identify water features (450, 550, and 650) in the travel path of vehicle 100 and to determine the position of vehicle 100 relative to the water features. As described above, a predetermined configurable threshold range may be employed. If the answer is no at 712, then at 714 a texture representation of the water features (450, 550, and 650) is determined, and at 716 the texture representation is overlaid on the water features in the map image. In an embodiment using a predetermined configurable threshold (distance between vehicle 100 and water feature 550) to a threshold range, at 712, method 700 proceeds to compare at 718 the (distance between vehicle 100 and water features (450, 550, 650)) with the threshold range. When the distance is greater than the threshold range, a first texture representation is determined at 722 and overlaid at 724. Once the distance becomes less than the threshold range at 720, a second texture representation is determined at 726 and overlaid at 728. It should be understood that when the second texture representation is utilized at 728, the first texture representation is removed. This is also the case whenever the method determines a new texture representation using different symbols and / or symbol patterns. After 728 and after 724, the method may end or may return to 710.

[0052] Accordingly, the exemplary embodiments discussed above provide a technically improved vision system 102 that determines texture representations of water features and encodes them for use in various display systems, and specifically for systems that cannot rely on color intensity for land / water / sky differentiation. The embodiments determine texture representations that vary in response to the distance between the platform and the water features.

[0053] Although at least one exemplary embodiment has been presented in the foregoing detailed description of the present invention, it should be understood that there are many variations. It should also be understood that the exemplary embodiment or embodiments are merely examples and are not intended to limit in any way the scope, applicability, or configuration of the present disclosure. On the contrary, the foregoing detailed description will provide those skilled in the art with a convenient guide for implementing the exemplary embodiments of the present invention. It should be understood that various changes may be made in the function and arrangement of the elements described in the exemplary embodiments without departing from the scope of the present invention as set forth in the appended claims.

Claims

1. A method for a vision system in a mobile platform, the method comprising: At a control module, Receiving terrain data from a terrain database; Receiving aircraft status data from a navigation system; Displaying a monochrome image on a monochrome display system that reflects a view from the current position of the mobile platform; Processing the terrain data and the aircraft status data to (i) Identify water body features, and (ii) Determine a texture representation of the water body features, the texture representation including symbols arranged in a related symbol pattern, the texture representation including symbols arranged in an associated symbol pattern, wherein the texture representation is determined based on a comparison of a threshold range with the distance between the aircraft and the water body features, such that when the distance between the aircraft and the water body features is greater than the threshold range, a first texture representation is determined as the texture representation; and When the distance between the aircraft and the water body features is less than or equal to the threshold range, a second texture representation different from the first texture representation is determined as the texture representation; and Texturing the water body features by covering only the water body features with the texture representation on the monochrome image.

2. A vision system for an aircraft, comprising: A navigation system; The monochrome display system carried by the aircraft; A terrain database; And A control module operably coupled to the navigation system, the monochrome display system, and the terrain database, the control module being configured to: Receive terrain data from the terrain database; Receive aircraft status data from the navigation system; Display a monochrome image on the monochrome display system that reflects a view from the current position of the aircraft; Process the terrain data and the aircraft status data to (i) Identify water body features, and (ii) Determine a texture representation of the water body features, wherein the texture representation includes symbols arranged in a related symbol pattern; and Texturing the water body features by covering only the water body features with the texture representation on the monochrome image Wherein the texture representation includes symbols arranged in an associated symbol pattern, and Wherein the control module is further configured to determine the texture representation based on a comparison of a threshold range with the distance between the aircraft and the water body features, such that when the distance between the aircraft and the water body features is greater than the threshold range, a first texture representation is determined as the texture representation; and When the distance between the aircraft and the water body features is less than or equal to the threshold range, a second texture representation different from the first texture representation is determined as the texture representation.

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