Abstract:
The invention is directed to an improved visualization and measurement system ( 15 ). In the preferred embodiment, the visualization system comprises: a video sensor ( 16 ) having a range of view ( 18 ), a field of view ( 19 ), and a video output signal ( 20 ), a non-contact instrument ( 21 ); having a measurement zone ( 22 ) and a measurement output signal ( 23 ), the instrument and video sensor being so configured and arranged that the measurement zone is aligned in the field of view; a processor ( 24 ) for processing the video output signal and the measurement output signal and for providing a processor output signal ( 25 ); a display device ( 26 ) for displaying the processor output signal; and a control device ( 28 ) for moving the field of view and measurement zone in the range of view. In the preferred embodiment, the processor includes an image processor ( 29 ) for combining the video output signal and the measurement output signal into a combined processor output signal, and the display device shows an indication ( 38 ) of the measurement zone. In the preferred embodiment, the video sensor is a video camera and the non-contact instrument is a pyrometer.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to the field of video monitoring systems and, more particularly, to an improved visualization system which allows for aiming a non-contact instrument and video sensor at an object and displaying both a visual image and an instrument reading from the targeted object on a display screen. 
     BACKGROUND ART 
     A variety of control room video systems are known in which the user may view an environment and measure parameters of the environment being viewed, such as the temperature of certain objects. An example of such a system is disclosed in U.S. Pat. No. 5,219,226, the aggregate disclosure of which is incorporated herein by reference. However, such systems have been limited in that they do not allow precise aiming of both the video sensor and the instrument at an object in the subject area of interest. 
     Hence, it would be useful to provide a measuring and visualization system which allows for the field of view of the video image to be moved within a broader range of view and the instrument to be visually aimed at targets within the field of view such that environmental measurements may be taken of specific objects within the range of view. 
     DISCLOSURE OF THE INVENTION 
     With parenthetical reference to the corresponding parts, portions or surfaces of the disclosed embodiment, merely for the purposes of illustration and not by way of limitation, the present invention provides an improved instrument visualization system ( 15 ) comprising a video sensor ( 16 ) having a range of view ( 18 ), a field of view ( 19 ), and a video output signal ( 20 ), a non-contact instrument ( 21 ) having a measurement zone ( 22 ) and a measurement output signal ( 23 ), the instrument and video sensor being so configured and arranged that the measurement zone is aligned in the field of view, a processor ( 24 ) for processing the video output signal and the measurement output signal and for providing a processor output signal ( 25 ), a display device ( 26 ) for displaying the processor output signal, and a control device ( 28 ) for moving the field of view and measurement zone in the range of view. 
     The processor may include an image processor ( 29 ) for combining the video output signal and the measurement output signal into the combined processor output signal. The display device may show an indication ( 38 ) of the measurement zone. The video sensor may be a color CCD image sensor, a CMOS image sensor, a Focal Plane Array image sensor, or an infrared image sensor. The non-contact instrument may be a pyrometer ( 21 ), a gamma radiation sensor, or a spectrometer. The control device may be manually operated from a position remote to the video sensor so as to move the field of view in the range of view, or the control device may be programmed to move the field of view along a preselected or a random path within the range of view. 
     Accordingly, the general object of the present invention is to provide an improved visualization system which allows for viewing an area and taking environmental measurements of objects within the area. 
     Another object of the invention is to provide an improved visualization system which allows the operator to change the field of view of the video sensor. 
     Another object of the invention is to provide an improved visualization system in which the operator may aim an instrument at an object within the field of view of the video sensor. 
     Another object of the invention is to provide an improved visualization system which provides environmental measurements of objects within the video sensor&#39;s field of view. 
     Another object of the invention is to provide an improved visualization system in which both a video image and environmental measurements from targeted objects are displayed to the operator. 
     Another object of the invention is to provide an improved visualization system in which the video output signal and the instrument output signal are combined into a combined signal which may be read by a display device. 
     Another object of the invention is to provide an improved visualization system in which an indication of the measurement zone of an instrument is shown on a display device. 
     Another object of the invention is to provide an improved visualization system in which the video sensor is a color CCD sensor. 
     Another object of the invention is to provide an improved visualization system in which the video sensor is a infrared sensor. 
     Another object of the invention is to provide an improved visualization system in which the instrument is a pyrometer. 
     Another object of the invention is to provide an improved visualization system in which the instrument is a gamma radiation sensor. 
     Another object of the invention is to provide an improved visualization system in which the instrument is an spectrometer. 
     Another object of the invention is to provide an improved visualization system in which the motion of the video sensor and the instrument may be controlled by an operator. 
     Another object of the invention is to provide an improved visualization system in which the operator may manually adjust the video sensor and instrument from a remote position. 
     Another object of the invention is to provide an improved visualization system in which the control device may be programmed to move the video sensor&#39;s field of view along a preselected or a random path. 
     Another object of the invention is to provide an improved visualization system in which the instrument measurements are stored for future retrieval and use. 
     Another object of the invention is to provide an improved visualization system in which a video sensor and an instrument are securely aligned within a field of view. 
     Another object of the invention is to provide an improved visualization system in which the center of the video sensor and the center of measurement zone of the instrument are aligned. 
     These and only objects and advantages will become apparent from the foregoing and ongoing written specification, the drawings, and the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic of the improved visualization system. 
     FIG. 2A is a perspective view of an alignment mechanism for the video sensor and instrument shown in FIG.  1 . 
     FIG. 2B is an enlarged view of a portion of the alignment mechanism shown in FIG.  2 A. 
     FIG. 3 is a block diagram of the processing for the visualization system. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions or surfaces consistently throughout the several drawing figures, as such elements, portions or surfaces may be further described or explained by the entire written specification, of which this detailed description is an integral part. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, debris, etc.) together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof, (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or access of rotation, as appropriate. 
     Referring now to the drawings and, more particularly, to FIG. 1 thereof, this invention provides an improved visualization and measuring system, of which the presently preferred embodiment is generally indicated at  15 . The system is shown as broadly including a pan/tilt mechanism  33 , a pan/tilt head  34 , a pan/tilt control device  28  and a visual display device  26 . 
     As shown in FIGS. 1,  2 A, and  2 B, pan/tilt head  34  is adjustably mounted to pan/tilt mount  35  by pan/tilt mechanism  33  such that pan/tilt head  34  may be moved relative to mount  35 . Pan/tilt mechanism  33  and pan/tilt head  34  are standard commercially available pan/tilt systems which allow an operator to move head  34  both horizontally and vertically with respect to mount  35 . One example of a suitable pan/tilt system is Pelco&#39;s Model PT550P, available from Pelco, Inc. of Clovis, Calif. 
     Pan/tilt head  34  houses pyrometer  21 , camera  16 , processor  24 , and power module  36 . In the preferred embodiment, camera  16  is a standard industrial video camera with a zoom lens. One example of a suitable camera  16  is Sony&#39;s Model No. SSC-CX-34, available from Sony Corp. of America, New York, N.Y. However, it is contemplated that camera  16  may be any type of commercially available video sensor, such as a color CCD image sensor, a CMOS image sensor, a focal plane array image sensor or an infrared vidicon tube image sensor. Camera  16  provides a video output signal to processor  24  which, in turn, causes a visual image of field of view  19  of camera  16  to be displayed on display device  26 . Camera  16  is mounted such that it receives light through view window  39 . In this way, the operator is provided with a visual image of the area in front of panel  55  of pan/tilt head  34 . 
     Pyrometer  21  is a radiation pyrometer which is capable of measuring the temperature of a heated object in its measurement zone  22  by focusing the thermal radiation omitted by the object. Pyrometer  21  provides a measurement signal which is proportional to the intensity of the radiation of a subject object and which is used by the pyrometer&#39;s built-in processor to determine the temperature of the object. Measurement zone  22  is the area in which pyrometer  21  is able to sense infrared radiation, and is dependent on the sensitivity of pyrometer  21  and the distance of the subject object from pyrometer  21 . Pyrometer  21  can be either a single or a two color ratio pyrometer. One example of a suitable pyrometer  21  is Raytek&#39;s Model No. MRISASF, available from Raytek Corp. of Santa Cruz, Calif. Pyrometer  21  provides a digital signal  23  of the temperature of the subject object to processor  24 . 
     While in the preferred embodiment a pyrometer is used, the invention contemplates that other commercially available noncontact instruments may be employed, such as a gamma radiation sensor, a spectrometer or a directional sound detector. 
     Both pyrometer  21  and camera  16  are powered by power supply  36 . Power supply  36  is shown as being an external supply source, but it is contemplated that a local power source such as a battery may be used. 
     As shown in FIG. 1, camera  16  has a field of view  19 . Field of view  19  is that area in which camera  16  can receive visible light and in turn provide an optical image without adjustment of pan/tilt head  34  in either the vertical or horizontal direction. Similarly, pyrometer  21  has a measurement zone  22  in which it can accurately receive radiation omitted by an object. Pan/tilt head  34  and pan/tilt mount  35  are orientated such that pan/tilt head  34  can rotate through at least ten degrees of horizontal rotation and five degrees of vertical rotation. Camera  16  is housed in pan/tilt head  34  and is orientated parallel to axis x-x of housing  34  such that its field of view changes relative to the rotation of pan/tilt head  34 . Pan/tilt head  34  is controlled by a standard pan/tilt controller  28 , which may be operated by a system user from a remote control room. Controller  28  is of the type sold by Pelco, Inc. under Model CM7500. Controller  28  also includes a zoom control for camera  16  by which an operator can zoom in or away from objects in camera  16 &#39;s field of view. 
     Video output signal  20  and pyrometer  21  &#39;s radiation measurement output signal  23  are sent to system processor  24 . System processor  24  is programmed to receive pyrometer temperature measurement output signal  23  and to format the calculated temperature value such that it is displayed on the display device  26  in real time with the visual image from camera  16 . In addition, system processor  24  is programmed to display a graphic indication  38  of the center of measurement zone  22  as well as the appropriate units of the temperature measurement of pyrometer  21 . Indication  38  is a graphical depiction of the central measurement point from which pyrometer  21  is receiving radiation. 
     As shown in FIGS. 2A and 2B, camera  16  is fixed to pan/tilt head  34  and is positioned such that it receives an optical image through view window  39 . Camera  16  is housed within a pan/tilt enclosure  34 , which protects and stabilizes camera  16 . 
     As shown in FIGS. 2A and 2B, pyrometer  21  is adjustably mounted to the base  41  of pan/tilt head  34  by alignment mechanism  42 . Alignment mechanism  42  holds pyrometer  21  over camera  16  and may be manually adjusted to align pyrometer  21  with the central axis of field of view  19  of camera  16 . Alignment mechanism  42  comprises a vertical plate  43  with lower rightwardly-extending horizontal mounting flange  44  and upper leftwardly-extending horizontal base flange  45 . Mounting flange  44  is fixably connected to pan/tilt head base  41 . 
     Pyrometer  21  is attached to pyrometer mounting plate  46 . Mounting plate  46  is, in turn, pivotally mounted to base flange  45  at a pivot connection  55  (not shown), which allows the sensing end  56  of pyrometer  21  to pivot left, right, up and down. 
     Thus, the front of pyrometer mounting plate  46  may be moved in both the horizontal and vertical direction relative to base flange  45 . Pyrometer mounting plate  46  is a generally flat planar member orientated on the same plane as base flange  45 . Vertical and horizontal adjustment of pyrometer  21  is effectuated by manual adjustment of pyrometer vertical adjustment  48  and horizontal adjustment  49 . 
     As shown in FIG. 2B, vertical adjustment  48  includes vertical adjustment block  50  and vertical adjustment screw  51 . Vertical adjustment block  50  is a solid rectangular member fixably mounted to the rear of pyrometer mounting plate  46 . A threaded throughbore extends down through vertical adjustment block  50  and, in turn, through pyrometer mounting plate  46 . This threaded throughbore is orientated in the vertical direction. Vertical adjustment screw  51  is threaded for movement through said vertical throughbore such that rotation of vertical adjustment screw  51  in the clockwise direction will move vertical adjustment screw  51  down through vertical adjustment block  51  and out the bottom of pyrometer mounting plate  46 . As the bottom of vertical adjustment screw  51  protrudes from the bottom of the vertical throughbore in pyrometer mounting plate  46 , it contacts the top of fixed base flange  45 . Thus, if adjustment screw  51  is adjusted further in the downward direction, the contact and pressure between the bottom of vertical adjustment screw  51  and the top of base flange  45  will cause the non-sensing end  58  of pyrometer mounting plate  46  to rise and the sensing end of pyrometer  21  to fall relative to pivot connection  55 . Alternatively, the rotation of vertical adjustment screw  51  such that it moves in the upward direction will cause lower sensing end  56  of pyrometer mounting plate  46  and pyrometer  21  to rise relative to pivot connection  55 . 
     As shown in FIG. 2B, horizontal adjustment  49  operates in much the same way but in the horizontal direction. Horizontal adjustment block  52  is attached to base flange  45  and is provided with a rectangular slip passage  53  through which the head of horizontal adjustment screw  54  extends. Slip passage  53  is enlarged such that the end of horizontal adjustment screw  54  is free to move vertically. Vertical adjustment block  54  includes a threaded horizontal throughbore orientated in the horizontal direction. Horizontal adjustment screw  54  is then threaded for movement through the horizontal throughbore such that rotation of horizontal adjustment screw  54  causes corresponding movement of pyrometer  21 . 
     In particular, horizontal adjustment screw  54 , slip passage  53  and the horizontal throughbore in vertical adjustment block  50  are orientated such that the rotation of horizontal adjustment screw  54  in the clockwise direction will cause vertical adjustment block  50  and, in turn, the non-sensing end  58  of pyrometer mounting plate  46  to pivot to the left and towards horizontal adjustment block  52 . Alternatively, rotating horizontal adjustment screw  54  in the counterclockwise direction will push non-sensing end  58  of pyrometer mounting plate  46  away from horizontal adjustment block  52  and cause sensing end  56  of pyrometer  21  to rotate to the left about pivot connection  55 . In this way, the alignment of pyrometer  21  relative to camera  16  may be adjusted. 
     Pyrometer  21  and camera  16  are aligned in the following manner with appropriate adjustment of horizontal and vertical adjustment screws  51  and  54 . The center of the field of view of camera  16  and the center of measurement zone  22  of pyrometer  21  must be minimally offset and almost perfectly parallel. As mentioned above, processor  24  is programmed to display a targeting artifact  38  (“cross hairs”) in the exact center of the image signal from camera  16 . Targeting artifact  38  is displayed on display device  26 . Artifact  38  provides the operator with aiming feedback for alignment of the pyrometer and for aiming the pyrometer from a remote location. 
     Generally, the alignment process uses the video sensor to establish the basic data plane of the system and sets up the video image of field of view  19  as the frame of reference from which camera  16  is initially aligned. Pyrometer  21  is then positioned in rough alignment with camera  16 . As mentioned above, pyrometer  21  is mounted on two axis adjustable mounting plate  42 , which includes precision adjustment screws  51  and  54 , as closely as possible to camera  16 . After this initial assembly, pan/tilt head  34  is placed on an adjustable calibration stand and pointed in the general direction of a bare ambient temperature wall distanced one hundred feet away from camera  16  and pyrometer  21 . A small, six inch diameter, high output, known variable radiation source is centered on the wall. With the video camera mounted on the alignment stand and energized, the output signal cable  20  is connected to a standard video monitor  26 . The image on the monitor includes targeting artifact  38 . The calibration stand is then adjusted to move the entire camera head assembly until the technician can see that the six inch diameter, high output, known variable source mounted on the wall is centered in the “cross hairs” of targeting artifact  38  shown on the video monitor screen. Vertical adjustment screw  51  and horizontal adjustment screw  54  are then adjusted until measurement zone  22  of pyrometer  21  has been positioned such that the measuring signal  23  of pyrometer  21  is at its highest output and most exact reading with respect to the known radiation variable source. When this optimal point is found, horizontal adjustment screws  54  and  51  are permanently affixed and the pyrometer and camera are considered aligned. 
     FIG. 3 is a block diagram of the data processing and control system. As shown, pyrometer  21  includes a multi-sensor interface and a data and signal processor. For a two color or ratio pyrometer, radiation is received in two wavelengths, S 1  and S 2 , and produces an output that is based upon the ratio of the intensity of radiation received in the two wavelengths. An analog-to-digital (AID) convertor converts the analog input to pyrometer  21  into digital form and the pyrometer&#39;s processor determines the temperature of the viewed object. The temperature reading in digital form  23  is then transmitted to system processor  24 . At the same time, an analog video signal  20  is received by system processor  24  from camera  16  and is digitized for further processing. The resultant digital video image corresponds to a two-dimensional array of pixels. 
     Thus, system processor  24  includes a processor board which handles five signals other than the typical electronic component power supply connections. These signals include camera  16 &#39;s composite video image signal  20 , pyrometer sensor temperature data signal  23 , the digital data signal to pan/tilt mechanism  33 , the zoom signal to camera  16 , and the connection to control device  28 . 
     System processor  24  produces digital outputs which are representative of the nonvariable graphic elements of artifact  38  and the temperature units of measurement. The constantly updated variable temperature digital signal  23  from pyrometer  21  is received by processor  24  and converted to an output representative of the value of the measured temperature of the subject object. 
     System processor  24  includes an image processor  29 , which receives the digitized video image, along with the variable and nonvariable digital outputs mentioned in the preceding paragraph. Image processor  29  responds by producing a combined digital signal which represents the video image generated by camera  16 , overlayed with the graphics representing artifact  38  and the temperature reading from pyrometer  21  with appropriate units. 
     Artifact  38 , temperature units, and the temperature data from pyrometer  21  are inserted in each frame of video signal from camera  16 . Within the image processor circuitry  29  of processor  24 , each frame of the video signal  20  from camera  16  is modified. In a preferred embodiment, processor  24  is able to modify at least 30 frames per second. The temperature data and units of measurement for the temperature data, either degree symbol C. or degree symbol F., are placed in an appropriate location, typically the bottom left corner of the image which is displayed on display  26 . Processor  24  is programmed to insert artifact  38  at the center of field of view  19  of camera  16 . This combined signal is then converted into an analog output signal  25  for display on monitor  26 . Monitor  26  may be at a remote location, such as in a control room. 
     Signal  25  also carries pan/tilt and zoom digital control signals from control device  28  to processor  24 . The pan/tilt and zoom signals are industry standard signals. Processor  24  receives information from control device  28  and transmits this information to camera  16  and pan/tilt mechanism  33 . In particular, the pan/tilt zoom interface digitizes and further processes the pan/tilt and zoom commands received from control  28  and relays such commands to pan/tilt mechanism  33  and camera  16 . As a result, pan/tilt head  34  can be moved in a horizontal or vertical direction and camera  16  may be zoomed in or away from objects in field of view  19 . 
     Modifications 
     The present invention contemplates that many changes and modifications may be made. The particular materials of which the various body parts and component parts are formed are not deemed critical and may be readily varied. 
     Therefore, while the presently-preferred form of the visualization system has been shown and described, and several modifications discussed, persons skilled in this art will readily appreciate that various additional changes and modifications may be made without departing from the spirit of the invention, as defined and differentiated by the following claims.