United States Patent (19)
`Colley
`
`IIIHIIII
`US005592382A
`11
`Patent Number:
`5,592,382
`(45) Date of Patent:
`Jan. 7, 1997
`
`54
`
`DIRECTIONAL STEERING AND
`NAVIGATION INDICATOR
`
`Rogoff, "Electronic Charts as the Basis for Integrated
`Marine Navigation', IEEE 1992, pp. 256-260.
`
`(75) Inventor: Jaime B. Colley, Laguna Niguel, Calif.
`73 Assignee: Rockwell International Corporation,
`Seal Beach, Calif.
`
`Appl. No.: 402,434
`21
`Filed:
`Mar 10, 1995
`(22
`(51) Int. Cl.' ............................ G06G 7/78; G08G 1/123
`(52) U.S. Cl. ..................................... 364/449.1; 364/444.1;
`364/447; 364/460; 340/990; 340/994; 342/357
`58) Field of Search ............................... 364/424.01, 444,
`364/449, 452, 458, 447, 460, 424.02; 342/357,
`358, 457; 840/988,989, 992,994, 995,
`425.5, 815.55, 815.78
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4,281,326 7/1981 Anderson .................................. 342/41
`4,466,068 8/1984 Degré et al. ...
`... 364/461
`4,590,569 5/1986 Rogoff et al. ...
`... 364f452
`4,623,966 11/1986 O'Sullivan .............................. 364,461
`4,692,869 9/1987 King et al. ..
`... 364/448
`4,893,127
`1/1990 Clarket al. .
`... 342/386
`5,179,385
`l/1993 O'Loughlin ............................. 342/76
`5,268,844 12/1993 Carver et al. ........................... 364,443
`OTHER PUBLICATIONS
`Fix et al., "Advance Reference System Cockpit Display
`Project", IEEE 1990, pp. 338-342.
`Ranson, "Navigating Between Computer Displays in Power
`Plants' IEEE 1993, pp. 273-277.
`
`Primary Examiner--Gary Chin
`Assistant Examiner-Tan Q. Nguyen
`Attorney, Agent, or Firm-George A. Montanye; David J.
`Arthur; Susie H. Oh
`
`ABSTRACT
`(57)
`A navigation and guidance system which directs a user
`toward a desired destination. Position and steering informa
`tion are integrated into a single display to allow the user to
`immediately determine whether the correct course is being
`traveled, and to inform the use of any directional changes
`which may be necessary to be directed toward the desired
`destination waypoint. The user's position and course are
`determined by a navigation system and indicated on the
`display as a directional pointing icon, such as a line or arrow.
`The destination is displayed as a point. The user's Point of
`Closest Approach (PCA) can then be calculated according to
`current position, course, and the position of the desired
`destination. As the use's course gets closer to the bearing of
`the destination waypoint the PCA indicator can correspond
`ingly shift with the user's movements. By superimposing the
`PCA over the destination waypoint, the user may precisely
`steer his or her craft to the desired destination.
`
`17 Claims, 3 Drawing Sheets
`
`34
`COG :
`36
`SOG :
`5
`SOG :
`14
`SMG :
`2
`DST :
`TTG : 3m
`
`240
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`200
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`
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`222
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`202
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`ASUS-1011, Page 1
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`U.S. Patent
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`Jan. 7, 1997
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`Sheet 1 of 3
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`5,592,382
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`
`FIG.O
`PRIOR ART
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`FIG. b
`PRIOR ART
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`ASUS-1011, Page 2
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`U.S. Patent
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`Jan. 7, 1997
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`Sheet 2 of 3
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`5,592,382
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`FIG.2
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`ASUS-1011, Page 3
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`U.S. Patent
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`Jan. 7, 1997
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`Sheet 3 of 3
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`5,592,382
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`--y
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`ASUS-1011, Page 4
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`1.
`DIRECTIONAL STEERING AND
`NAVIGATION INDICATOR
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`5,592,382
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`2
`to indicate whether the user is successfully steering toward
`the desired path, immediate course correction is difficult.
`
`SUMMARY OF THE INVENTION
`The present invention is directed to a navigation and
`guidance system which directs a user toward a desired
`destination. Position and steering information are integrated
`into a single display to allow the user to immediately
`determine whether the correct course is being traveled, and
`to inform the user of any directional changes which may be
`necessary to be directed toward the desired destination. The
`desired destination is displayed on an electronic charting
`system by a destination waypoint. Several segment way
`points define an optimum route to reach the destination
`waypoint. Accordingly, the desired destination is repre
`sented by a destination waypoint.
`The actual track of the user is displayed relative to the
`Segment waypoints such that the user's actual track is
`Superimposed over the optimum route. The user's position
`and COG are determined by the navigation system and
`indicated on the display as a directional pointing icon, such
`as a line or arrow. The user's Point of Closest Approach
`(PCA) can then be calculated according to several functions:
`1) the user's current position; 2) the position of the desired
`destination; and (3) the user's COG. The PCA is indicated at
`or near the end of the user's actual pointing icon so that as
`the user's course gets closer to the destination waypoint
`bearing, the PCA pointer can correspondingly shift with the
`user's movements.
`Ultimately, the user may precisely direct his or her craft
`to the destination waypoint by simply overlaying the PCA
`pointer over the destination waypoint and maintaining that
`particular course. The overlaid icons represent the direc
`tional information relating to the course-over-ground and
`bearing information. When the two icons are overlaid, the
`COG will match the bearing to destination value. That is,
`when the user's actual location coordinates superimpose
`those of the destination waypoint, such that the icon repre
`senting the user or the user's craft is displayed over that of
`the destination waypoint, it can be determined that the user
`has arrived at the desired destination.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIGS. 1(a) and 1(b) show a conventional charting display
`scheme in which two display screens depict graphical and
`numerical positioning and correction information.
`FIG. 2 is a schematic view of an integrated steering
`indicator display in accordance with a preferred embodiment
`of the present invention.
`FIG.3 is an enlarged view of the steering indicator of FIG.
`2.
`
`DETALED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`The following description is of the best presently con
`templated mode of carrying out the invention. In the accom
`panying drawings, like numerals designate like parts in the
`several figures. This description is made for the purpose of
`illustrating the general principles of the invention and should
`not be taken in a limiting sense. The scope of the invention
`is best determined by reference to the accompanying claims.
`Embodiments of the present invention utilize data
`retrieved from a variety of navigation systems, such as the
`global positioning system (GPS), LORAN, inertial naviga
`
`BACKGROUND OF THE INVENTION
`
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`1. Field of the Invention
`The present invention relates to navigation and steering
`Schemes for use in marine, land, and air directional control.
`More particularly, the present invention relates to the display
`and expression of position and navigation information in a
`simple and direct format for immediate identification of the
`user's present location relative to a desired location.
`2. Description of Related Art
`Advances in data storage and display technologies have
`made electronic charts a necessary means to efficiently and
`accurately assist users in determining their positions relative
`to a desired destination. For example, when electronic charts
`are integrated with a positioning system such as the global
`positioning system (GPS), the user's position can be dis
`played in real time on a chart depicting the user's area. Such
`information is particularly useful for operators of marine,
`land, and air vehicles who continuously need to know of
`their positions around the earth. However, simply knowing
`one's position on a chart is generally not sufficient. It is also
`particularly helpful to know whether the present course of
`direction is correct. That is, users typically need to know if
`their present course will take them where they want to go.
`The desired destination could be the next waypoint on the
`route or some other location on the chart.
`Current commercially available electronic chart display
`implementations typically indicate relevant geographic fea
`tures, routes and waypoints, the user's position, and the
`user's track. However, such displays do not include inte
`grated steering information informing the user whether (1)
`the user's current course is properly directing the user towed
`the desired destination, and (2) any course corrections are
`needed to ensure the user arrives at this destination. Rather,
`in conventional chart display schemes, a separate display
`medium must be implemented. However, to review the
`additional course information, the user must switch between
`a position display and a steering correction display for a
`complete understanding of the total navigation situation.
`For example, FIG. 1(a) shows the current implementation
`in most commercial systems. A desired route with dotted
`waypoints 102 is indicated by the straight lines 104 which
`comprise the intended track 114. The destination waypoint is
`shown as a circled dot 110, and the dotted line 112 indicates
`the user's actual track. In the example, the arrow 116 at the
`top end of the dotted line 112 shows the user's position and
`current heading. However, to retrieve steering data and
`correction information, the user must refer to FIG. 1(b). FIG.
`1(b) represents a steering screen which is used to correct a
`current route and, thus, to enable users to steer themselves
`toward a desired destination waypoint. That is, the object of
`the steering screen is to point the illustrated arrow 118
`toward the flag 120. When the arrow 118 points at the flag
`120, the course-over-ground indication (COG) will match
`the bearing indication (BRG).
`However, to reach the point where the user is traveling
`toward the destination waypoint, numerous attempts at
`directing and redirecting the arrow toward the flag may be
`required. Consequently, however, the user must switchback
`and forth from screen-to-screen to determine if the track is
`correct according to the graphical as well as numerical
`representation. Because there are no visual or graphical cues
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`5,592,382
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`tion, and/or radar systems in conjunction with Point-of
`Closest-Approach (PCA) calculations. The PCA is the point
`along the current course that is closest to a predefined
`destination. That is, the point at which the user or the user's
`craft will pass closest to the desired destination can be
`determined according to the location coordinates of the
`destination, the user's position relative to the earth, and the
`direction of the craft. The PCA is then displayed in a single
`screen format to represent steering information.
`By displaying the PCA on a chart concurrently with the
`course, bearing, and position information, the user is given
`an immediate view of the navigation requirements, and can
`respond accordingly. Users are made aware of where they
`are; they know where they want to go; and, with the PCA
`displayed, they know how close they are going to be if they
`continue along the current course. Thus, to reach the desired
`destination, a user only needs to steer toward a course which
`places the PCA over the destination point.
`As illustrated in the preferred embodiment of FIG. 2, a
`single display screen 200 is shown. A computer 202 is
`programmed 204 to drive the position displays 240 includ
`ing, for example, the course-over-ground (COG) indication,
`bearing data (BRG), the speed over ground (SOG), speed
`made good (SMG), distance to waypoint (DST), and the
`time to go (TTG). The numerical table or listing 240 is
`optional in that the numerical data is embodied by the
`movement of the graphical icons illustrated in the display
`200. Accordingly, reference to a numerical coordinates table
`is unnecessary for steering and position correction or adjust
`lent.
`Embodiments of the invention operate with navigation
`hardware (not shown) which is implemented to provide
`information concerning the user's current position, the
`user's COG data, and the position/coordinates of the desired
`destination. For example, the navigation hardware may
`include a GPS receiver or LORAN receiver, as well as
`display devices and/or electronic charts, in conjunction with
`a programmable computer to drive the displays.
`Thus, preferably the display 200 shows a graphical rep
`resentation of numerical data combined with instantaneous
`course correction information. The actual track 216 of the
`user is designated as a dotted line. The PCA 210 is shown
`relative to the user's current position 218 and the destination
`waypoint 220. A bearing-to-destination (BTD) indicator 212
`connects the destination waypoint to the user's current
`position showing the direction from the user's position to the
`destination waypoint.
`In preferred embodiments, a COG indicator 214 is
`coupled to the current position icon 218 to provide a clear
`50
`indication of the direction of travel of the user. The COG
`214, in conjunction with the PCA 210 and the BTD indicator
`212, allows the user to immediately respond and react to
`information indicating that he or she may be moving away
`from the destination waypoint 220. Thus, by attempting to
`align the COG indicator 214 with the bearing-to-destination
`indicator line 212 and by overlaying the PCA over the
`destination waypoint, the user is immediately visually
`informed as to whether further steering adjustments should
`be made to accurately direct the user toward the destination
`waypoint.
`Consequently, as illustrated in the preferred embodiment
`of FIG. 2, by combining two display implementations, a
`significant navigation difficulty can be solved with a single
`display manifested as a computer screen. Embodiments of
`the present invention provide a means to inform the user
`which way to steer or turn his or her craft and to allow the
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`user to immediately confirm the navigational changes, and
`then proceed to the destination waypoint. Simultaneously,
`the user can determine his or her progress along the intended
`track and/or the current position on the chart. By combining
`PCA and BTD data, the user is able to make immediate and
`spontaneous adjustments to the desired track, and concur
`rently confirm the adjustments.
`More particularly, in FIG. 3, the BTD indicator 212, the
`COG indicator 214, and the PCA 210 are illustrated in
`enlarged detail. As explained above, by combining the
`steering and navigation indicators into a single, integrated
`display system 200 (FIG. 2), users can quickly and easily
`determine their current locations relative to the desired
`destinations 220, and how to best reach the desired desti
`nations.
`An origin waypoint 310 represents one of the segment
`waypoints, as shown in FIG. 2. The origin waypoint is often
`described with respect to point-to-point navigation, which
`allows the user to follow multiple straight-line segments
`along a route. The origin waypoint indicates the beginning
`of the leg, while the destination waypoint indicates the end
`of the leg. By connecting the points along the route, each
`origin and destination waypoint describes a leg of the route,
`which is shown in FIG.3 as a desired track 312. Ideally, the
`user's actual track 216 (FIG. 2) will be superimposed over
`the desired track, as the user moves from waypoint to
`waypoint. Thus, each time the user switches to another leg
`of the desired track 312, the previous destination waypoint
`becomes a new origin waypoint for the next leg.
`In the preferred embodiment of FIG.3, it will be seen that
`the length of the BTD indicator 212 will vary according to
`the location of the current position 218 relative to the
`destination waypoint 220. Similarly, the distance 314
`between the current position 218 and the PCA 210 will
`increase as the user turns toward the destination waypoint
`220. The distance 314 will reach its largest value when the
`user or the user's craft is pointing directly at the destination
`waypoint, such that the PCA 210 is superimposed over the
`destination waypoint 220.
`It will be recognized that the circumferential track of the
`PCA indicator about the current position indicator will vary
`between a circular shape and a heart shape. As the distance
`between the current position and the PCA depends on the
`user's position relative to the destination waypoint, the point
`of closest approach generally maintains a very small sphere
`or track about the current position. The distance between the
`user and the PCA reaches a maximum value when the user
`is pointing directly at the destination waypoint, and it
`reaches a minimum value when the user is pointing exactly
`90 degrees from the destination waypoint. This generally
`ensures that the PCA will remain visible on the display.
`Accordingly, in preferred embodiments, as the computer
`and software arrangement continuously determines the COG
`and BRG values, and the corresponding graphical represen
`tations are displayed on the steering screen, the user can
`manually or automatically direct the PCA indicator 210
`toward the destination waypoint 220. Since the distance
`between the destination waypoint 220 and the PCA 210 vary
`according to the movement of the user relative to the
`destination waypoint 220, the user can see immediately how
`close he or she will come to the target destination. Once the
`PCA 210 superimposes the destination waypoint 220, the
`user can conclude that by continuing in the selected path, he
`or she will ultimately arrive at the desired destination.
`As can be seen in FIGS. 2 and 3, the COG indicator 214
`is a gross indicator. The COG indicator 214 simply shows
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`the general direction in which the user is headed. Depending
`upon the precision and relative size of the display markings,
`even if the COG indicator 214 matches, i.e., appears to lay
`over, the BTD indicator 212, error may be present, espe
`cially over long distances.
`In preferred embodiments of the present invention, the
`destination waypoint 220 is placed in an arrival circle 316
`(FIG. 3) for additional ease of steering adjustment. The
`arrival circle 316 provides a more precise indication to the
`user that he or she is moving closer to the desired destina
`tion. Preferably, the computer/program assembly includes
`an alarm system 222 Such that when the user's current
`position indicator 218 enters the arrival circle 316 an alarm
`will be triggered and generate beeping sounds or flashing
`lights. In this way, the user is informed that he or she getting
`very close to the destination waypoint, and a change in
`heading, speed, or both may be required.
`A wide variety of data, display, and other steering imple
`mentations have been described herein. It should be appre
`ciated, however, that other information may be included in
`the steering indicator embodiments of the present invention.
`In an alternate embodiment of the present invention, and as
`discussed briefly above, a variety of alphanumeric data may
`be included in the display. For ease of installation, manu
`facturers may desire to retrofit embodiments of the present
`25
`invention into existing display schemes. Accordingly, the
`computer may be programmed to incorporate the graphical
`steering and directional representations of the present inven
`tion into the steering screen provided by existing conven
`tional charts such as that shown in FIG. 1(b).
`While display system embodiments discussed above
`relate to a user steering a craft, such as a boat or aircraft, it
`will be recognized that embodiments of the invention may
`be incorporated into almost any type of moving object,
`system, or simply carried by a person. Applications for the
`present invention may vary widely. Any application where
`latitude, longitude, and course information is available may
`utilize steering indicator embodiments of the present inven
`tion. For example, hikers or horseback riders may find it
`useful to have a guidance tool which can enable them to
`determine whether they are on a correct course, and what
`changes to make if they are not.
`This detailed description is set forth only for purposes of
`illustrating examples of the present invention and should not
`be considered to limit the scope thereof in any way. Clearly
`numerous additions, substitutions, and other modifications
`can be made to the invention without departing from the
`scope of the invention which is defined in the appended
`claims and equivalents thereof.
`I claim:
`1. A system for indicating directional information to a user
`having a current position traveling on a current course
`toward a desired destination, comprising:
`a computer having a display;
`a navigation system coupled to the computer for provid
`ing position and course data;
`means for determining a point of closest approach (PCA)
`to the desired destination in accordance with the
`desired destination, the user's current position, and
`current course, the desired destination having an asso
`ciated waypoint representing the desired destination on
`the display;
`means for indicating integrated steering information to the
`user including:
`means for informing the user whether the current
`course will direct the user to the waypoint, and
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`means for correcting the current course of the user to
`enable the user to reach the waypoint by directing the
`PCA to coincide with the waypoint; and
`means for displaying the corrected current course to the
`user, wherein the user's current position and course, the
`PCA, the desired destination, and the integrated steer
`ing information are simultaneously and integrally dis
`played on the computer display.
`2. A positioning apparatus for indicating integrated direc
`tional and point of closest approach (PCA) information to a
`user traveling along a current course toward a desired
`destination, the positioning apparatus operable with a com
`puter and a navigation system providing the user's current
`position data, destination position data, bearing data, and
`course-over-ground (COG) data, comprising:
`destination position means for indicating the position of
`the desired destination;
`current position means for indicating the current position
`of the user relative to the desired destination;
`PCA means for indicating a position along the current
`course that is closest to the desired destination;
`COG position means for indicating the COG data, the
`COG position means coupled to the current position
`means, wherein the COG data represents the direction
`of travel of the user at the user's current position,
`further wherein the PCA means is coupled along a line
`formed by the current position means and the COG
`position means;
`bearing-to-destination (BTD) means for integrally cou
`pling the destination position means with the current
`position means; and
`alignment means for aligning the COG position means
`with the BTD means such that the PCA means coin
`cides with the destination position means, wherein the
`user is oriented such that the COG means superimposes
`the BTD means, further wherein when the PCA means
`coincides with the destination position means, the
`user's current course is directed toward the desired
`destination.
`3. The positioning apparatus of claim 2, further compris
`ing display means for displaying the destination position
`means, the current position means, the PCA means, the COG
`position means, and the BTD means, such that as the
`alignment means aligns the COG position means with the
`BTE) means, the PCA means gets closer to the destination
`means, wherein when the PCA means matches the destina
`tion position means, the PCA means superimposes the
`destination position means.
`4. The positioning apparatus of claim3, further compris
`ing an arrival indicator for indicating that the PCA means is
`getting closer to the destination position means.
`5. The positioning apparatus of claim 4, further compris
`ing an alarm for indicating that the PCA means has reached
`the arrival indicator.
`6. The positioning apparatus of claim 2, further compris
`ing numerical data means for indicating to the user numeri
`cal information regarding the COG position, the distance
`between the user's current position and the desired destina
`tion.
`7. The positioning apparatus of claim 3, wherein the
`display means is a computer screen.
`8. The positioning apparatus of claim 2, wherein the
`distance between the current position means and the PCA
`means varies as the COG position means is aligned with the
`BTD means.
`9. The positioning apparatus of claim 2, wherein the
`navigation system comprises the global positioning system.
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`10. The positioning apparatus of claim 2, wherein the
`navigation system comprises a LORAN navigation system.
`11. The positioning apparatus of claim 2, wherein the
`navigation system comprises an inertial navigation system.
`12. An integrated steering indicator operable with a pro- 5
`grammable computer and a navigation system, the inte
`grated steering indicator for displaying point of closest
`approach (PCA), route, and position information to a trav
`eling operator, to direct the operator from an origin to a
`desired destination, the origin and desired destination having 10
`an associated origin waypoint and a destination waypoint,
`respectively, the positions of the origin and destination
`waypoints being determined by the navigation system,
`respectively, the integrated steering indicator comprising:
`an origin waypoint indicator for displaying the position of 15
`the origin waypoint;
`a destination waypoint indicator for displaying the posi
`tion of the destination waypoint relative to the origin
`waypoint;
`a current position indicator for indicating a current posi
`tion of the operator;
`a course-over-ground (COG) indicator integrally coupled
`to the current position indicator for indicating a direc
`tion of travel of the operator;
`a PCA indicator positioned in line with the COG indica
`tor,
`a bearing-to-destination (BTD) indicator defining a line
`between the destination waypoint and the operator's
`current position;
`means for steering the COG indicator toward the desti
`nation waypoint such that the PCA indicator moves
`toward the destination waypoint indicator, wherein as
`the PCA indicator moves toward the destination way
`35
`point indicator, the operator travels toward and in the
`direction of the desired destination; and
`alignment means for aligning the COG indicator with the
`BTD indicator such that the PCA indicator superim
`poses the destination waypoint indicator, such that the
`operator is traveling directly toward the desired desti
`nation.
`13. The integrated steering indicator of claim 12, further
`comprising
`icons for representing the origin waypoint, destination 45
`waypoint, COG, BTD, PCA, and current position indi
`cators, and
`a screen coupled to the computer for displaying the
`representative icons.
`14. The integrated steering indicator of claim 13, further 50
`comprising an arrival indicator encompassing the destina
`tion waypoint indicator for indicating when the PCA indi
`cator is within a predetermined distance to the destination
`waypoint.
`15. The positioning apparatus of claim 14, further com- 55
`prising an alarm for indicating that the PCA indicator has
`reached the arrival indicator.
`16. A method for steering a user having a current position
`toward a desired destination, wherein the user moves in a
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`direction of travel associated with course-over-ground
`(COG) data, comprising the steps of:
`providing location information of the user's current posi
`tion, the desired destination, and the user's COG data
`representing the user's direction of travel;
`displaying the position of the desired destination;
`simultaneously indicating the current position of the user
`relative to the desired destination;
`displaying the COG data integrally with the user's current
`position to indicate a direction of travel of the user;
`displaying a point-of-closest-approach (PCA) of the
`user's current position integrally with the user's direc
`tion of travel, wherein the PCA indicates whether the
`user will reach the desired destination according to the
`user's current direction of travel; and
`aligning the PCA with the desired destination, such that
`when the PCA superimposes the position of the desired
`destination, the user's current direction of travel accu
`rately matches the bearing of the desired destination.
`17. A positioning apparatus for integrally displaying
`directional and point of closest approach (PCA) information
`to a user traveling along a current course toward a desired
`destination, the positioning apparatus operable with a com
`puter and a navigation system providing the user's current
`position data, destination position data, bearing data, and
`course-over-ground (COG) data, wherein the user's current
`position data, destination position data, bearing data, and
`COG data are graphically represented on the computer, the
`positioning apparatus comprising:
`a display coupled to the computer;
`destination position means for indicating the position of
`the desired destination on the display;
`current position means for indicating the current position
`of the user relative to the desired destination on the
`display;
`PCA means for displaying a position along the current
`course that is closest to the desired destination;
`COG position means for indicating the COG data on the
`display, the COG position means coupled to the current
`position means, wherein the COG data represents the
`direction of travel of the user at the user's current
`position;
`bearing-to-destination (BTD) means for integrally cou
`pling the destination position means with the current
`position means; and
`alignment means for enabling the COG position means to
`be aligned with the BTD means, the PCA means being
`displayed to move toward the destination position
`means, such that the user is oriented to cause the COG
`means to move closer to the BTD means, wherein when
`the PCA means coincides with the destination position
`means the display indicates that the user's current
`course is directed toward the desired destination.
`
`ASUS-1011, Page 8
`
`