Abstract:
A live video system provides live video monitoring of subject matter in a hazardous zone located in a poor radio frequency (RF) transmission area. A camera sealed against contamination captures video images of the subject matter in the hazardous zone. The camera sends the live video images over a camera cable connected to a live reel. The live reel may be located in the hazardous zone and has a feed cable on the live reel electrically connected to the camera cable as the feed cable is paid out from the live reel. This feed cable extends from the live reel to a transmission station located outside the poor RF transmission area. The transmission station has a RF transmitter connected to the feed cable. The RF transmitter transmits the video signal to a receiving station.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to video systems that can be used to view hazardous material environments from a remote location. More particularly, the invention relates to video systems for hazardous material and environments hardened against radio frequencies (RF).  
       BACKGROUND OF THE INVENTION  
       [0002]     Personnel for hazardous material environmental teams are selected with a variety of subject matter skills so as to deal with multiple types of subject matter in the hazardous environments. However, it is not possible to have a person on the team for each possible subject matter. Therefore, it often occurs that a video system is used to transmit an image of the subject matter in the hazardous material environment, i.e. hazardous zone, outside of the hazardous zone so that a person skilled in the type of subject matter but not skilled in handling hazardous materials can view the situation in the hazardous zone.  
         [0003]     In the past this has been accomplished by using a video camera carried by a HAZ-MAT person into the environment to capture the images of the hazardous zone on video media. The video media can then be reviewed later by a skilled person familiar with the subject matter in the hazardous zone.  
         [0004]     There are several problems in using a video camera in a hazardous zone. First, the camera needs to be protected from contamination in the hazardous zone or the camera will need to be destroyed and packaged with the contaminated materials when it comes out of the hazardous zone. Second, capturing the images in the hazardous zone on a video recording does not provide a real time viewing of what is happening in the hazardous zone to the person outside the zone who is the most skilled in working with the subject matter and equipment in the zone.  
         [0005]     This latter problem can be solved by placing an RF transmitter with the video system in the hazardous zone so that live video is transmitted from the hazardous zone. However, such an implementation may not be operative in certain hazardous material environments. For example, if the hazardous zone is in a building, the RF transmission from the building may be poor and erratic. Further, if the hazardous material is in a room that is designed to be RF-free, i.e. hardened against RF energy, then RF transmissions from the room will be blocked by the room&#39;s construction. Also if the hazardous material environment contained radiation sources or other environmental conditions that prevented the transmission of signals by radio frequency or other electromagnetic radiation, then live broadcasting from the hazardous zone is probably not possible.  
       SUMMARY OF THE INVENTION  
       [0006]     In accordance with this invention the above and other problems have been addressed by a live video system that provides live video monitoring of subject matter in a hazardous zone even when the hazardous zone is located in a poor electromagnetic radiation transmission area. The live video monitoring is provided to a monitor station in a clean zone by using a video camera at the hazardous zone. The camera is resistant to contamination and captures the video images of the subject matter in the hazardous zone. The camera sends the live video images over a camera cable connected to a live reel. The live reel is located also in the hazardous zone and has a feed cable on the live reel electrically connected to the camera cable as the feed cable is paid out from the live reel. This feed cable extends from the live reel to a transmission station located outside the poor electromagnetic radiation transmission area. The transmission station has a transmitter connected to the feed cable. The transmission station receives the video signal over the feed cable and transmits the video signal from the transmitter to a receiving station. The receiving station is located in a clean zone and has an electromagnetic radiation receiver receiving the video signal transmitted from the transmission station. A monitor in the clean zone receives the video signal from the receiving station and displays the live video image captured by the video camera in the hazardous zone.  
         [0007]     In another aspect of the invention, the live reel is mounted on a rolling dolly whereby the live reel may be easily moved into the hazardous zone. The feed cable on the live reel will pay out to the transmission station as the live reel is moved. Further, a battery for supplying power to the video camera can be mounted on the rolling dolly.  
         [0008]     In another aspect of the invention, the video camera, the feed cable, the battery pack are all electrically connected by electrical plugs so that one or more of the camera, the feed cable or the battery pack may be easily replaced.  
         [0009]     These and various other features as well as advantages, which characterize the present invention, will be apparent from a reading of the following detailed description and a review of the associated drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  shows a preferred embodiment of the video system of the present invention.  
         [0011]      FIG. 2  shows a sealed video camera and its cable with connectors and mounting hardware and a power cable from a battery pack to the cable of the video camera.  
         [0012]      FIG. 3A  shows a sealed battery pack.  
         [0013]      FIG. 3B  shows the electrical connector for receiving the power plug at the battery pack.  
         [0014]      FIG. 4  shows a live reel mounted on a two wheel dolly.  
         [0015]      FIG. 5  shows a mount for the battery pack on the frame of the two wheel dolly and a mount for the camera and its cable on the frame of the dolly. 
     
    
     DETAILED DESCRIPTION  
       [0016]      FIG. 1  shows one preferred embodiment for a video system in accordance with the present invention. A video camera  102  is electrically connected to a live reel  104  and a battery pack  106  by flexible camera cable  108 . Camera cable  108  carries a video signal from the camera  102  and also carries DC power from the battery pack  106  to the camera  102 . Connectors  107  and  109  for short cables at the battery pack  106  and at the live reel  104  are respectively an M-type plug for the power pack  106  and an RCA-type plug for the video cable  108 .  
         [0017]     The live reel  104  carries a large amount of feed cable  110 . This cable could be any type of good signal cable including twisted pair or coax. Coax provides the least amount of signal loss for lengthy runs. Typically about 800 feet of coax cable  110  would be on the reel  104 . Live reel  104  has a collector assembly hub  112 . The collector assembly hub  112  provides electrical continuity between the camera cable  108  and the feed cable  110  on the live reel  104 .  
         [0018]     The live reel  104  and the battery pack  106  are carried on a dolly  114 . Dolly  114  is roller mounted on wheels  115  so that it may be easily moved by a user of the video camera  102 . The dolly  114  might be a two wheel dolly as depicted in  FIGS. 4 and 5  or it might be a four wheel trolley as depicted in  FIG. 1 . In another embodiment, the trolley configuration could also be implemented as a remote-controlled, powered trolley with a remote-controlled camera mounted on the trolley.  
         [0019]     The feed cable  110  from the live reel  104  is connected to a transmitter cable  119  at a transmission station  116 . A video signal transmitted from the transmission station  116  is received at receiver station  118 . The receiver station  118  passes the signal from a receiver  120  to monitor  122 .  
         [0020]     At the transmission station  116 , transmitter  117  receives the video signal over the transmitter cable  119  through connector  121  connecting the transmitter cable  119  to the feed cable  110 . The pluggable connector  121  is preferably an RCA plug. The transmitter  117  encodes the video signal for RF transmission. The RF signal is transmitted from transmission antenna  125 . A sealed battery pack  124  at the transmission station  116  provides power to the transmitter  117 .  
         [0021]     At the receiving station  118 , receiver antenna  127  receives the transmitted signal from transmission station  116 . Receiver  120  decodes the transmitted signal, generates the video signal and passes the video signal to monitor  122  over receiver cable  123 . A sealed battery pack  126  provides power to the receiver  120  and the monitor  122 . Each of the battery packs  106 ,  124  and  126  are interchangeable so as to provide power redundancy in the system. Typically the receiving station  118  would have its own power supply, and its battery pack  126  would be used as backup for the other two battery packs  106 ,  124 .  
         [0022]     In operation, the system is connected up and the camera  102  turned on so that its image may be viewed at monitor  122 . If everything is in working order, then a user in a hazardous material suit can pull the dolly  114  into the hazardous zone and carry the camera  102  or mount it on the dolly  114 . The feed cable  110  would be physically attached at a rigid mount near the transmitting station  116 . Thus, as the dolly  114  was pulled into the hazardous zone such as a building, feed cable  110  would pay out from the rotating live reel  104 .  
         [0023]     When the hazardous zone is inside a building, the transmission station  116  will be mounted outside the building. It is of course possible to mount the transmission station  116  in a select area in the building that has good electromagnetic radiation transmission characteristics. However, most buildings do not have good RF transmission characteristics, and in fact some rooms may be designed specifically to be hardened against radio frequency signals. Therefore, the transmission station  116  is probably best mounted outside of a building. Further, the transmission station  116  could also be mounted in the hazardous zone if there is not enough feed cable  110 . However, this is not desirable as then the transmission station  116  must be decontaminated after its use. If decontamination is not possible, it would be disposed of and replaced.  
         [0024]     As depicted in  FIG. 1  in most configurations of the system, the dolly  114 , live reel  104 , battery pack  106 , camera  102  and cables  108  and  110  will be in the hazardous or contaminated zone. Since the battery pack  106  and camera  102  are sealed they will likely be able to be decontaminated after the system has been used. Likewise, the live reel  104  can usually be decontaminated after its usage in a hazardous material zone. Feed cable  110  could be decontaminated but usually the expense of decontaminating the cable  110  is not worth the cost, and the feed cable  110  is usually replaced after use in a hazardous material zone.  
         [0025]      FIG. 2  shows the sealed video camera  102  with its camera cable  108  and mounting hardware  204 . Sealed video camera  102  is a Super-Mini: SM-50 B&amp;W Camera available from Powerlynx, St. Petersburg, Fla. Mounting hardware  204  may be used to mount the camera  102  on a pistol grip for easy use by the user. This also allows proper orientation of the camera  102  on the pistol grip so that the user can simply point the camera  102 .  
         [0026]     The camera cable  108  includes a power cable and a video cable. The power cable terminates with an M-type connector  107 B. The video cable of the camera cable  108  terminates with RCA plug  109 .  
         [0027]     The power from the sealed battery pack  106  in  FIG. 1  is provided over power cable  210 . A power connector  107 A on cable  210  is an M-type connector  107 A and plugs into the M-type connector  107 B on the camera cable  108 . A power plug  214  is a cigarette lighter type plug and plugs into an outlet on the power pack shown in  FIGS. 3A and 3B .  
         [0028]     In  FIG. 3A  the sealed battery pack or power pack  106  is shown opened to display the battery  304  and a storage location for the power plug  214 . A sealed power plug outlet  308  on the wall of the sealed power pack  106  is shown in  FIG. 3B . The power plug  214  plugs into the power plug outlet  308 . While other power packs might be used, the power pack  106  pictured in  FIGS. 3A and 3B  is Watersafe power pack available from Powerportstore.com. It is a water-tight sealed power pack, and thus can likely be decontaminated after use in a hazardous material zone.  
         [0029]      FIG. 4  shows an embodiment of a two wheeled dolly. Frame  402  of the two wheel dolly has live reel  104  attached to the dolly. A live reel handle  405  is attached with bolt  406  to the frame  402  of dolly. A base of the reel  104  is bolted to plate  408  of the dolly. The feed cable  110  ( FIG. 1 ) is shown wound on the live reel  104  and a connection from the collector assembly hub  112  is also shown in  FIG. 4 .  
         [0030]      FIG. 5  shows the dolly frame  402  of the two wheel dolly in  FIG. 4  with a hook assembly  502  to hold the battery pack  106  and a hanger assembly  504  to hold the camera  102  with its camera cable  108 . Hook assembly  502  provides hooks  503  for hanging the battery pack in  FIG. 3A  by its handle on frame  402 . The hanger assembly  504  in  FIG. 5  provides a place to wind the camera cable  108 . The camera  102 , once a pistol grip is mounted on the bottom of the camera  102 , can be mounted on the hanger assembly  504  by inserting the grip into the opening  506  of the hanger assembly  504 . The hanger assembly  504  can be fabricated simply out of plastic and fastened to the frame  402 , or it may be fashioned out of metal and welded or bolted to the frame  402 .  
         [0031]     In other embodiments the camera is a video/audio camera. A microphone is mounted with the camera and audio cables are added to the camera cable, feed cable, transmitter cable and receiver cable. Further, the transmitter  117  and receiver  120  could be connected by cable rather than using RF transmission through antennas  125  and  127 .  
         [0032]     It will be appreciated by one skilled in the art that there are also many variations on the dolly and other various components of the video system. It is important that each of the components be easily replaced and easily reconnected into the system—thus the use of readily available cables and pluggable connectors.  
         [0033]     While the invention has been particularly shown and described with referenced to preferred embodiments thereof, it will be understood by those skilled in the art that various other changes in the form and details may be made therein without departing from the spirit and scope of the invention.