Abstract:
A method and apparatus for simultaneously displaying secondary data with primary data using an interactive display system. The invention allows for a user to generate views of the secondary data alongside or superimposed on a graph of the primary data. The method and apparatus may be used to display test data involving multiple dimensions, such as RPM, vibration and displacement trend data collected from multiple sensors during the testing or monitoring of a machine.

Description:
FIELD 
       [0001]    This invention relates to the field of data display. More particularly, this invention relates to a system for displaying data in a more user-friendly and efficient manner. 
       BACKGROUND 
       [0002]    Data display technology has become a paramount tool in the information age. The need for data analysts to have large sums and varied types of data at their fingertips has never been more desirable. However, as many types of data analysts, including engineers, soldiers, pilots, and executives, have come to realize, the display of too much data at one time has the potential of undermining an original purpose of the data collection—to understand the current status and trends of a particular system or systems. When the addition of data translates into less clarity for an analyst, the perceived benefit of having more information actually becomes a detriment for the analyst. Based on these realities, many data accumulation and display technologies incorporate creative ways to package large sums of data into understandable and meaningful information for an analyst. 
         [0003]    For example, in manufacturing and other industrial environments, machines are often monitored to detect faults and verify proper operation. A machine&#39;s vibration may be continuously monitored and alarms generated if the vibration exceeds a predetermined threshold at some frequency of interest. Practically any number and type of variable, including temperature and fluid pressures, may be monitored. These monitoring systems typically incorporate various types of sensors attached to one or more monitored machines. These sensors generate signals that are transferred to a computer where they are analyzed and in some cases stored for future reference. 
         [0004]    Monitoring of systems is most critical when a the system is undergoing some type of transition. For example, during the start up of a large turbine, close monitoring of any vibrations of the rotor is essential to prevent possible damage. During the period while the state of the system is changing, sensor data is collected continuously. Such data, collected during system transients, is commonly referred to as transient data. Depending on the item being monitored (e.g., a machine, an animal, the environment) and the type of data collected, transient data sets and other similar data sets are typically displayed on two-dimensional dynamic plots for active analysis. These data displays often provide a primary graphical view showing the interrelation of two primary trend variables of interest, such as rotations per minute (RPM) versus time for a rotating machine. The type of data that is primarily monitored depends on the monitored item and the related process. 
         [0005]    In a considerable number of monitoring applications, a number of important variables other than the primary trend variables are monitored. These “secondary” variables may be of interest to the analyst, but not as critical to the minute-by-minute operation of a particular monitored item and related process. In many monitoring applications, the simultaneous display of all of the sensory data, primary and secondary, at a display device can be overwhelming to the analyst. Similarly, the intermittent display of all or most of the sensory input with many displays being presented in a monotonous series may have the effect of confusing an analyst as to what is being displayed at any given time or, perhaps worse, causing an analyst to become complacent because of the ever-changing views shown on the display. 
         [0006]    What is needed, therefore, is the ability to continuously monitor dynamic primary trend variables while retaining the option to select a point or region on the primary trend data plot and obtain a graphical “snapshot” of one or more secondary data variables at the selected point or region. 
       SUMMARY 
       [0007]    The above and other needs are met by a method for displaying multidimensional data on a display device, where the multidimensional data includes primary data and secondary data. The method includes the steps of (a) displaying a graph of at least a portion of the primary data on the display device in a first graphing format, (b) selecting a first reference point in the displayed graph of the primary data, (c) accessing a first requested data set from the secondary data, where the first requested data set is indicated by the first reference point, and (d) displaying a graph of the first requested data set in a second graph superimposed on the display device with the graph of the primary data. Employing this embodiment of the method, a user generates a “snapshot” of the behavior related to the one or more types of secondary data corresponding to the selected first reference point in the primary data. 
         [0008]    In preferred embodiments, a user selects a graph format for the secondary data, and then selects a particular range of data points in the primary data using an input device (e.g., a mouse), thereby defining the first requested data set. The interactive display device then displays the secondary data corresponding to the first requested data set, so that the selected portion of the secondary data is displayed with the primary data. 
         [0009]    Preferably, the first requested data set is displayed in a display window on the display device with the graph of the primary data. In some embodiments, the display window is superimposed over at least a portion of the graph of the primary data. The user may adjust a transparency setting associated with the superimposed display window so that the superimposed display window does not fully block the graph of the primary data. Additionally, the display window may be repositioned along the display device based on a user&#39;s viewing preference. The display window may also be expanded, minimized or maximized. 
         [0010]    In another aspect, the invention provides an apparatus for displaying multidimensional data including primary data and secondary data. In preferred embodiments, the apparatus includes an interactive display system and plot-on-plot computer software and/or firmware running on the interactive display system. Primary data is displayed on a monitoring screen that is part of the interactive display system. A mouse, touchpad, touch screen or other similar input means are used to input a graphing format selection for the interactive display device using. A user may also select a reference point along the displayed primary data using the input device. Upon selection of a reference point, the application software and/or firmware operates to access a requested data set and display the requested data set in the chosen graph format along with the primary data on a display screen of the interactive display system. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Further advantages of the invention are apparent by reference to the detailed description in conjunction with the figures, wherein elements are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein: 
           [0012]      FIG. 1  depicts a preferred embodiment of an apparatus for generating plot-on-plot displays including an interactive display system in communication with a mass storage device; 
           [0013]      FIG. 2  depicts a view of two-dimensional primary data (RPM versus time) displayed using an interactive displayed device according to a preferred embodiment of the invention; 
           [0014]      FIG. 3  depicts a view of primary data (RPM versus time) displayed with one selection of secondary data graphed as an orbital plot at a particular point in the primary data; 
           [0015]      FIG. 4  depicts a view of primary data (RPM versus time) displayed with a plurality of selections of secondary data graphed as orbital plots at selected points in the primary data; 
           [0016]      FIG. 5  depicts a view of primary data (shaft centerline plot) displayed with a plurality of selections of secondary data graphed as orbital plots at selected points in the primary data; and 
           [0017]      FIGS. 6 and 7  depict methods for generating plot-on-plot displays according to preferred embodiments of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]      FIG. 1  depicts a preferred embodiment of an apparatus for implementing the plot-on-plot data display methods described herein. As shown in  FIG. 1 , the apparatus includes an interactive display device  30  which preferably includes on-board memory  32  for storing or loading data to be displayed. The on-board memory  32  may be in the form of volatile memory, non-volatile memory or a combination of both. The device  30  also includes a display screen  34  which may comprise a CRT, LCD or plasma screen, or any other similar display means known to those skilled in the art. The display device  30  may incorporate a handheld device  36  that is operable to display the primary and secondary data as described herein and to at least receive data via wireless communication. In a preferred embodiment, a separate user input device  38 , such as a mouse, touchpad, touch screen or other similar input device, is in communication with the interactive display device  30 . In another embodiment, a user may interact with the display device  30  directly, such as by using a touch screen, interactive voice commands or other similar direct communication means. In preferred embodiments, the interactive display device  30  interacts with a server or other device connected to local area network, wide area network, the Internet or any other communication network. 
         [0019]    In a preferred embodiment, the interactive display device  30  is in communication with a mass storage device  40  via a communication network  42 . Alternately, the mass storage device  40  may be contained within the interactive display device  30 . The mass storage device  40  may be any nonvolatile data storage device in which a large quantity of data is stored, such as a magnetic or optical hard drive or a flash memory device. The communication network  42  may comprise any means of communicating data, such as a hardwired network (e.g., electrical or fiber-optic), a wireless network (e.g., infrared or RF) or a combination of hardwired and wireless networks. In the preferred embodiment, requests for data (including primary data or secondary data requests) are sent via the communication network  42  to the mass storage device  40 , and the requested data is provided to the interactive display device  30  via the communication network  42 . 
         [0020]      FIG. 2  shows a first graph  2  of data displayed on the display screen  34  of the interactive display device  30 . The first graph  2  shows primary data  4  plotted in a two-dimensional format. In this example, the primary data  4  is displayed as RPM versus time for a turbine during a time period in which turbine operation transitions from a lower speed state to a higher speed state and is then held at the higher speed state. The time component is measured along the X-axis  6  and the RPM component is measured along the Y-axis  8 . The first graph  2  also shows a plurality of graph icons  10  from which a user can select the manner in which to plot secondary data. For example, a user may select an orbital graph icon  11  to generate an orbital plot of relative shaft position versus rotation angle. It should be understood that the methods and apparatus described herein are not limited to any particular type of graphical representation. Thus, the invention is applicable to any number of dimensions, any sources or types of data and any manner of graphically representing data. 
         [0021]    With reference to  FIGS. 1 ,  3  and  6 , the primary data  4  is plotted in the first graph  2  on the display screen  34  of the interactive display device  30  (step  100 ). A user then selects a graphing format for displaying secondary data by selecting the orbital graph icon  11  from among the plurality of graph icons  10  (step  102 ). Subsequent or prior to the selection of the graphing format for the secondary data, the user selects a first reference point  12  on the graph of the primary data  4  (step  104 ). In a preferred embodiment, selection of the first reference point  12 , defines a first requested data set containing secondary data. Thus, the first requested data set is a set of secondary data associated with the primary data  4  displayed at the first reference point  12 . During or subsequent to the selection of the first reference point  12 , a subplot  14  comprising a graphical representation of the first requested data set is superimposed on the first graph  2  (step  106 ). In the preferred embodiment, the format of the subplot  14  corresponds to the graph icon previously selected by the user (e.g., the orbital graph icon  11 ). Preferably, an indicator  16  also appears with the subplot  14  to visually associate the subplot  14  with the selected reference point  12 . 
         [0022]    With reference to  FIGS. 3 and 7 , another embodiment of the method is described. As in the previously described embodiment, primary data  4  is displayed (step  200 ) and a first reference point  12  is selected by the user (step  202 ). Subsequent to the selection of the first reference point, the user submits a request for secondary data of interest corresponding to the selected first reference point  12  (step  204 ). In situations wherein there are multiple sources of secondary data, step  204  includes submitting a request for a particular source of secondary data. The submission of the request for secondary data may be made in several different ways. In a preferred embodiment, the process of submitting the request for secondary data (step  204 ) includes (1) selecting a particular source of secondary data (step  204   a ) and (2) selecting a specific type of graphical output format to be used when displaying the requested secondary data on the interactive display device  30  (step  204   b ). In some embodiments, the selecting step ( 204   a ) and the submitting step ( 204   b ) may be combined into one step such that the selection of a first reference point  12  also operates as a submission of a request for secondary data corresponding to the first reference point  12  (e.g., if only one type of secondary data is available). 
         [0023]    After the submitting the request for secondary data (step  204 ), the requested data set is accessed and displayed as a sub-plot  14  with the primary data  4  (step  206 ). The indicator  16  is preferably displayed with the subplot  14  indicating the approximate position of the reference point  12  with which the requested data set is associated. Although the indicator  16  in  FIG. 3  is shown as a connecting line, it should be understood that any visual means to correlate the sub-plot  14  with the selected reference point  12  may be used, including curved lines, object indicators (such as footnote-type indicators), color code schemes and other similar indication methods known to those skilled in the art. 
         [0024]    The reference point  12  may correspond to a single datum of primary data  4  or it may indicate a range of one of the dimensions of the primary data  4 , such as a time range. Additionally, the user may select a range of the primary data  4  using a mouse or other similar selection device to click and drag a virtual enclosure (e.g., a virtual box) around a particular portion of the primary data  4 , thereby defining a first reference point. In the examples shown in  FIG. 3 , the secondary data represents orbital data indicating the relative position of the center of rotation of a shaft of a turbine in its bearings. In these examples, the secondary data is displayed with the primary data as a subplot  14  (step  106 ,  FIG. 6 ) so that a user has a static view or “snapshot” of the orbital behavior of the shaft at a time corresponding to the reference point  12  of the primary data  4 . The secondary data depicted in the subplot  14  need not be static. In some preferred embodiments, the subplot  14  depicts a replay of “live” data from the period of time corresponding to the reference point  12  (such as in a repeating loop). Alternatively, the primary data  4  may also be live and the user (with a single keystroke) attaches the subplots of secondary data as the primary data develops. 
         [0025]    In a preferred embodiment, the subplot  14  is in the form of a display window that may be repositioned within the first graph  2  (step  108   a ). The indicator  16  preferably associates the subplot  14  with the reference point  12  no matter where the subplot  14  is moved within the graph  2 . Also, the subplot  14  may preferably be manipulated to be made more or less transparent or its relative size changed based on user interaction with the interactive display device  30 . In a particular embodiment, using plot-on-plot software operating on the interactive display device  30 , a fade command is selected by a user to selectively adjust the transparency of the subplot  14  on the display screen  34  to a desired level (step  108   b ). In another embodiment, a user manipulates a mouse or other similar device to move a screen indicator (such as a common pointer indicator) to adjust the relative size of the subplot  14  (step  108   c ). 
         [0026]    With reference to  FIG. 6 , in some preferred embodiments, a step of loading a requested data set (step  105 ) is performed after the submission of a request for secondary data. This loading step may include the transfer of a requested data set from an external storage device  40  to memory  32  within the interactive display device  30 . (See  FIG. 1 .) In another embodiment wherein secondary data is stored in digital memory  32  within the interactive display device  30 , the loading step is conducted completely within the interactive display device  30 . After the requested data set is loaded (step  105 ), the secondary data making up the requested data set is displayed on the interactive display device along with primary data (step  106 ). 
         [0027]      FIG. 4  depicts an example graph  2  wherein RPM is plotted on the Y-axis  8  versus time on the X-axis  6  for the shaft of a turbine. The secondary data displayed in  FIG. 4  relates to a particular position “P” along the shaft of the selected turbine monitored by at least two sensors so that accurate orbital data (i.e., the relative position of the shaft and bearings at position “P”) may be acquired.  FIG. 4  depicts an example of operation of an embodiment of the invention wherein a user selects a plurality of reference points  18  (such as points  18   a ,  18   b ,  18   c ,  18   d ,  18   e  and  18   f ) on the graph of the primary data  4 . The approximate locations along the primary data  4  of the selected reference points  18  are indicated by corresponding indicators  19  (such as indicators  19   a ,  19   b ,  19   c ,  19   d ,  19   e  and  19   f ). The indicators  19  correspond to subplots  20  (such as subplots  20   a ,  20   b ,  20   c ,  20   d ,  20   e , and  20   f ). In this specific application example, a user may simultaneously obtain a display of RPM data (primary data) and orbital data (secondary data) in a user-friendly format that better communicates to the analyst the positional status of the monitored shaft at various times during turbine start-up. In preferred embodiments, different graphing formats may be selected for each of the subplots  20  of the secondary data. 
         [0028]    After displaying the data as shown in  FIG. 4  the user may remove the subplots  20  and start over by selecting a new source of secondary data. For example, the user may submit a request for secondary data corresponding to a position “Q” along the shaft that is separate and distinct from the position “P”. In addition, a user may select a graph icon other than the orbital graph icon  11  so that the newly requested secondary data is displayed with the primary data  4  in a different format. A user may also select a first reference point in the primary data  4  and request corresponding secondary data from one secondary data source (e.g., from sensors at position “P” on the shaft), and then select a second reference point in the primary data  4  and request corresponding secondary data from another secondary data source (e.g., from sensors at position “Q” on the shaft). In this way, the two different sources of secondary data can be simultaneously displayed with the graph of the primary data  4 . It will be appreciated that secondary data from any conceivable combination and number of data sources could be displayed in combination with a common source of primary data. Similarly, any combination and number of graphical representations can be selected to correspond with the various requested secondary data sets, limited only by available screen space on the display screen  34  and the memory capacity of the memory  32  of the interactive display device  30 . As mentioned before, the application examples shown in  FIGS. 2-4  are for illustration only and are not meant to be limiting in any way. 
         [0029]      FIG. 5  depicts a second graph  22  of primary data  24 . In this illustrative example, the primary data  24  corresponds to the average centerline position of a turbine shaft relative to a fixed centerline position of the overall turbine apparatus. Although the primary data  24  gives an analyst an idea of where the average center position of the shaft is at any given time, the primary data  24  alone cannot give the analyst the necessary information to know the extent of vibration of the shaft (i.e., the extent of the radial movement of the shaft at any given point as it rotates). As in the prior embodiments a user can select a particular graphing format for the secondary data by selecting a graph icon, such as an orbital graph icon. A user may then select a first reference point  25   a , thereby defining a data set including orbital data (secondary data) at a particular location along the shaft, such as point “P.” In this example, point “P” on the shaft may correspond to the location of a bearing and related sensors for gathering data. Upon selection of the first reference point  25   a , an orbital subplot  26   a  with a corresponding indicator  28   a  is generated. A user can then select one or more other reference points, such as  25   b  and  25   c , thereby initiating generation of subplots  26   b  and  26   c  with corresponding indicators  28   b  and  28   c . The resultant display including subplots  25   a ,  25   b  and  25   c  gives an analyst a good indication of the movement of the shaft within its bearings at position “P” as well as the average centerline position of the shaft. 
         [0030]    It will be appreciated that means for selecting reference points in the data and means for submitting requests for data (such as secondary data) include a combination of hardware components of the apparatus, such as the embodiment depicted in  FIG. 1 , as well as plot-on-plot computerware (software and/or firmware) operating on the interactive display device  30 . The computerware, coupled with the interactive display device  30  allows a user to interact with the interactive display device  30  as shown in  FIGS. 2-5  and as described with reference to the methods of  FIGS. 6 and 7  as described herein. 
         [0031]    The foregoing description of preferred embodiments for this invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.