Abstract:
A navigation system takes a graphical input and translates it into an alpha-numeric entry generally including latitude and longitude information. The system interprets the graphical entry, determines if a waypoint already exists or is depicted at the geographical location identified by the graphical entry and creates a new waypoint if no waypoint already exists or is depicted at the geographical location.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and is a divisional of U.S. patent application Ser. No. 11/069,420 filed Feb. 28, 2005, which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention generally relates to electronic data entry systems and specifically to electronic data entry systems with graphical scratchpad fillers for use in aircraft navigation systems. 
       BACKGROUND 
       [0003]    Flight management in large commercial aircraft generally includes a flight management system (FMS). The FMS typically includes a central computer unit which integrates flight information and enables the pilot to manipulate flight information. Flight information may include, for example, aircraft position data, flight plan data, instrument approach information, and/or any other information which may pertain to flight management. 
         [0004]    The FMS is generally connected to some sort of display unit, such as, for example, a central display unit (CDU), with which the FMS displays flight management information for use by the pilots. The CDU generally has an area on the screen which displays information prior to entry by the pilot called a scratchpad. The scratchpad displays characters as they are entered on a keyboard by the pilot. Thus, the pilot is able to check his/her data entry work prior to entry into the FMS. 
         [0005]    For example, when interacting with a navigation system, the pilot generally enters any needed data into the FMS via the keyboard. Flight plan information generally includes, but is not limited to, waypoint and leg information. Waypoints are series of points that, when connected, identify a flight path. Therefore, modifications to the flight path (or flight plan) generally include modifications to and additions or deletions of waypoints and/or waypoint data. Waypoints may be pre-existing, pre-defined waypoints generally approved by some sort of authoritative body, such as the FAA, or the waypoints may be user defined. Waypoint information generally includes a waypoint name, an identifier code, and latitude and longitude information, among other items. 
         [0006]    When the pilot needs to modify, add, and/or delete flight plan data, he/she generally enters waypoint information into the FMS and views the information on the scratchpad area of the CDU. The pilot generally must enter alpha-numeric characters of some sort to identify the waypoint. Another way to identify a waypoint is to define the new waypoint as a bearing and distance from an already defined waypoint. This method of waypoint identification also involves entering alpha-numeric characters into the scratchpad. 
         [0007]    The process of determining waypoint information and entering it into the FMS via the CDU and alpha-numeric characters is both time consuming and requires considerable cognitive effort by the pilot. 
         [0008]    The present invention is directed to overcoming one or more of the problems or disadvantages associated with the prior art. 
       SUMMARY 
       [0009]    An aircraft navigational system with a graphical scratchpad filler is provided including a processor which runs a software program, an electronic display which displays navigational data, a flight management computer including a central display unit with a scratchpad area, and a cursor control device. The user may use the cursor control device to control a cursor on the electronic display and select points on the electronic display for entry into the scratchpad area of the central display unit. 
         [0010]    A method of filling a scratchpad area on a central display unit is provided, including selecting a location on an electronic display with a cursor control device, converting the selected location to latitude and longitude coordinates, and comparing the latitude and longitude to a set of displayed points on the electronic display. Either the latitude and longitude or one of the points displayed on the electronic display may be sent to the scratchpad area on the central display unit 
         [0011]    The features, functions, and advantages can be achieved independently in various embodiments of the present invention or may be combined in yet other embodiments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  shows an aircraft and a flight deck within the aircraft. 
           [0013]      FIG. 2  is a schematic diagram of one embodiment of a graphical scratchpad filler. 
           [0014]      FIG. 3  is an example of a Flight Management Computer including a scratchpad area. 
           [0015]      FIG. 4  is an example of a navigational display. 
           [0016]      FIG. 4A  is the navigational display of  FIG. 4  showing a temporary waypoint symbol. 
           [0017]      FIG. 5  is an example of one embodiment of a logic diagram illustrating how the software of the graphical scratchpad filler may operate. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Turning now to  FIG. 1 , an aircraft  10  generally includes a flight deck  15  from which pilots may control the operation of the aircraft  10 . The flight deck  15  may include stations  20  for one or more pilots, one or more electronic displays  30  and at least one cursor control device (CCD)  40 . 
         [0019]      FIG. 2  illustrates one embodiment of a graphical scratchpad filler  100 . The graphical scratchpad filler  100  may be integrated with a flight management computer (FMC)  110  which may have a memory  112  containing a software program  114 . The memory  112  may also include a database  115  which may include waypoint information. The FMC  110  may be operatively connected to a central display unit (CDU)  120  which may be an electronic display for displaying flight management information. The FMC  110  may also be operatively connected to the cursor control device (CCD)  40 . The CCD  40  may enable the pilots to control a cursor on a navigational display for selection and entry of information into a scratchpad area  310  ( FIG. 3 ) of the FMC  110 . 
         [0020]    Although the components of the graphical scratchpad filler  100  have been described with reference to aircraft systems, the components of the graphical scratchpad filler  100  may be more general in nature, for example, a computer of any sort could be substituted for the FMC  110  and an electronic display of any sort may be substituted for the CDU  120 . Additionally, the electronic display may be, for example, a cathode ray tube (CRT) display, a liquid crystal display (LCD), a plasma display, a projection display, a touch screen display, or any other type of electronic display. 
         [0021]      FIG. 3  depicts one embodiment of the FMC  110  that may be integrated with the graphical scratchpad filler  100  of  FIG. 2 . The FMC  110  may have a CDU  120  including a scratchpad area  310 , line select keys  304  and entry keys  306 . Generally, flight management information is displayed on the CDU  120  for reference and manipulation by the pilot. The pilot enters data into the FMC  110  via the line select keys  304  and the entry keys  306 . The line select keys  304  may allow the pilot to select options or choices available on the CDU  120 . If the pilot needs to enter data into the FMC  110 , for example, new waypoint data, the data entry keys  306 , which may represent alpha-numeric characters similar to a keyboard, may be used for data entry. When the pilot enters data via the entry keys  306  (and in some cases the line select keys), the entries appear in the scratchpad area  310 , and this may allow the pilot to check his/her work prior to execution. Final entry of data from the scratchpad area  310  into the FMC  110  may be accomplished with an execute key or an enter key (neither shown), or by selecting one of the line select keys  304 . 
         [0022]      FIG. 4  is an example of a navigational display (ND)  400 . The ND  400  may be any type of electronic display which displays positional information for an aircraft and/or flight plan information for the aircraft. The ND  400  may also include a partial compass rose  412  and an aircraft heading and/or track indication  414 . An aircraft flight plan generally includes waypoints  430  and legs  420   a ,  420   b ,  420   c  which connect the waypoints. Additionally, different types of waypoints may be displayed, active waypoints  430  and background waypoints  440 . The active waypoints are locations, identified by latitude and longitude, over or through which the aircraft  410  will pass and which identify points in the flight plan. In other words, the active waypoints  430  define the flight plan and the legs  420   a ,  420   b ,  420   c  connect those waypoints. Background waypoints  440  may also be displayed on the ND  400 . Background waypoints  440  may be predefined waypoints contained within the database of the FMC  110 . These background waypoints  440  may help the pilots change the flight plan in response to, for example, air traffic control instructions or weather deviations. Additionally, a cursor  450  may be displayed on the ND  400  and controlled by the CCD  40 . 
         [0023]      FIG. 5  shows a logic diagram  500  illustrating a procedure which may be followed by the graphical scratchpad filler  100  embodied in  FIG. 2 . The graphical scratchpad filler may begin at  510  by determining whether the scratchpad area  310  on the CDU  120  (shown in  FIG. 3 ) is empty, meaning there is no text currently displayed in the scratchpad area  310 . If the scratchpad area is not empty, or is displaying text, the graphical scratchpad filler  100  may continue to monitor the condition of the scratchpad until the scratchpad is empty. 
         [0024]    Once the graphical scratchpad filler  100  has determined that the scratchpad area  310  is empty, the graphical scratchpad filler  100  may then determine if a waypoint pick mode is active at  512 . The waypoint pick mode may be a mode within the graphical scratchpad filler  100 , selected by the user, which tells the graphical scratchpad filler  100  that the user is searching for a waypoint. If the waypoint pick mode is not active at  512 , the graphical scratchpad filler  100  may continue to monitor the scratchpad area at  510  and the waypoint pick mode at  512 . If however, the waypoint pick mode is active at  512 , the graphical scratchpad filler  100  may then determine whether the waypoint pick mode has been cancelled at  514 . If the waypoint pick mode has been cancelled at  514 , the graphical scratchpad filler  100  may again monitor the scratchpad area at  510  and the waypoint pick mode at  512 . 
         [0025]    If the waypoint pick mode has not been cancelled at  514 , the graphical scratchpad filler may convert the position of the cursor  450  on the ND  400  ( FIG. 4 ) to a point defined by a latitude and a longitude. This conversion may be performed by using the Sodano Equation shown below: 
         [0000]    
       
         
           
             NewLat 
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                                   3444.053898 
                                 
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         [0026]    Where: 
         [0027]    New Lat is the latitude of the cursor point 
         [0028]    New Long is the longitude of the cursor point 
         [0029]    refLat is a reference latitude 
         [0030]    refLong is a reference longitude 
         [0031]    ΔX is the difference in the X direction between the reference point and the cursor position on the ND 
         [0032]    ΔY is the difference in the Y direction between the reference point and the cursor position on the ND 
         [0000]    This conversion may also be performed by any equivalent equation that projects a point on a sphere onto a plane. 
         [0033]    After the graphical scratchpad filler  100  has converted the cursor position to a point of latitude and longitude at  516 , the cursor may be checked at  518  to determine whether a displayed point, such as, for example, a waypoint, an airport, a NAVAID, a station, or any other displayed point, is located within a preset distance from the cursor location. In one embodiment, the preset distance is a 0.25 inch radius about the cursor  450 . In this way, the user may effectively “filter” which points may be checked by selecting the appropriate level of detail on the ND  400 . For instance, if the user would like to check for any background waypoints  440  which may allow him/her to modify the flight plan to avoid weather, the user may select background waypoints  440  for display on the ND  400  before selecting the waypoint pick mode. In this way, the background waypoints may be displayed on the ND  400  and be available for the graphical scratchpad filler  100  to check. Conversely, if the user would like to check for a diversion airport, he/she may select airports or stations for display on the ND  400  prior to selecting the waypoint pick mode on the graphical scratchpad filler  100 . In this way, the user may selectively “filter out” unwanted data on the ND  400  and thereby speed up the selection process and ultimately the process of modifying the flight plan if desired. 
         [0034]    If a displayed point is located within the preset distance of the cursor  450 , the displayed point may be highlighted and the identification of the point shown on the ND  400  at  520 . Identification of a point in aviation generally includes a one to seven letter code which uniquely identifies the point. The code may be stored in a database along with information specific about the point, such as, for example, latitude and longitude, point type (i.e. beacon, TACAN, VOR, VORTAC, airport, etc.), magnetic variation, servicing agency, frequency, or any other desired information about the point. 
         [0035]    The user may select the highlighted displayed point on the ND  400  at  522  by activating the cursor control device  130  ( FIG. 2 ). Once selected, the graphical scratchpad filler  100  may send the point identification (two to four letter code) to the scratchpad area  310  of the FMC  110  ( FIG. 3 ) at  524  and place a temporary waypoint symbol  451  ( FIG. 4A ) on the ND  400  with the point identification at that location at  531 . Once the data has been sent to the scratchpad area  310 , the user may then modify the flight plan per normal operation of the FMC  110 . 
         [0036]    If, however, there is no displayed point on the ND  400  within the predefined distance of the cursor at  518 , the graphical scratchpad filler  100  may display the latitude and longitude of the point (determined at  516 ) at  526 . Once the latitude and longitude of the point is displayed at  526 , the user may select this latitude and longitude at  528  by activating the cursor control device  130 . If the user selects the latitude and longitude at  528 , the latitude and longitude may be sent to the scratchpad area  310  of the FMC  110  at  530  and a temporary waypoint symbol  451  with the latitude and longitude may be placed on the ND  400  at the selected location at  533 . Again, once the latitude and longitude is sent to the scratchpad area  310 , the user may modify the flight plan per normal operation of the FMC  110 . 
         [0037]    Other aspects and features of the present invention can be obtained from a study of the drawings, the disclosure, and the appended claims.