Abstract:
Mobile Digital Video Recorders (MDVR) for security applications can require extensive storage requirements as video quality, video resolution, and camera counts increase. Frequently, the storage requirements over many days or weeks exceed the capacity of any one storage device leading to the use of multiple storage devices. However, ruggedized storage devices that are usable within a moving vehicle platform are expensive and have lower capacity capabilities per unit, and thus place a limit upon the storage that may be used within any single vehicle. This invention employs a mixed configuration of rugged and non-rugged storage devices in combination with robust control software modules to achieve the total on-board storage requirements of the system economically and without requiring special accommodation within a vehicle for a high number of storage devices.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]    The operating environment for mobile digital video recorder and its associated storage when installed within a vehicle is a challenging one. The system must be able to perform without pause for a number of complete duty cycles, each cycle of which commonly lasts for 18 hours, while subjected to vibration, temperature, and shock levels to which stationary equipment is never exposed, and for which standard storage devices are not designed to withstand. Standard storage drives, which are cost effective, cannot maintain continuous operation in this type of environment, and hardened drives built for automotive or military applications, are cost prohibitive in that they may cost as much as 200 times as much as standard storage devices. 
         [0002]    Data storage requirements are a limiting factor on the operational capability of a mobile digital video recording (MDVR) system used in security applications. An MDVR system for such applications has extensive storage requirements as system specifications require sufficient storage for multiple duty cycles for each operational vehicle. Storage requirement demands continue to increase over present levels as requirements for video quality, video resolution (higher definition), camera count, and vehicle counts increase. An MDVR system that can meet the storage requirements for multiple duty cycles, can withstand the rugged mobile environment, can be expandable to meet ever growing storage needs, and yet is cost effective is needed. 
       BACKGROUND OF THE INVENTION  
       [0003]    Typical MDVR systems on the market today attempt to meet storage requirement needs for operational vehicles that have a requirement for 30, 60, and even 90 days of onboard storage. The typical system design for a vehicle-based system with 90 days of onboard storage would require 10 to 12 2.5″ commercial hard drives to be installed within the vehicle. To accomplish this, the hard drives, not normally suitable for use in such a rugged environment, would require elaborate and expensive protection means from on-board environmental conditions to allow them to continue to function. Using 2.5″ commercial drives is an improvement over 3.5″ drives in terms of withstanding the on-board environmental conditions, but at a sacrifice of storage capacity as 2.5″ commercial drives have less than 25% of the capacity of a 3.5″ disk drive. Thus, the storage needs encompass a number of on-duty cycles for each vehicle in the system. 
         [0004]    In addition, the elaborate means required for protection of the commercial drives to ensure continued operation in such a rugged environment increases both the installed cost and maintenance cost of the system. A solution is needed that provides protection for standard commercial storage devices within an on-board environment that will provide for temperature, vibration, and shock protection, meet the needs of a vehicle that requires storage for multiple vehicle duty cycles, and provides this protection at a reasonable cost per installed system. 
         [0005]    The instant invention is a novel, non-obvious and cost effective means for capturing and storing an integrated stream of video, audio, and meta-data captured by an operating MDVR system by employing a mixed configuration of rugged and non-rugged storage to compensate for the harsh operating environment and yet achieve the total storage requirements of the system across multiple vehicle duty cycles. 
       SUMMARY OF THE INVENTION  
       [0006]    The instant invention employs a mixed configuration of rugged and non-rugged storage devices, environmental sensors and other vehicle operating sensors, and a set of software modules for management of the storage devices to achieve the total storage requirements of the system without compromising the operational characteristics of the storage devices. 
         [0007]    The invention comprises a MDVR and a Mobile Storage Array (MSA) connected by a high speed interface such as External SATA, USB 2.0, or IEEE 1394 and a set of software modules for system command and control. The MSA comprises an array of non-rugged commercial storage components such as 3.5″ hard disk drives with very large capacity, environmental sensors, and power supply, command and control, and environmental sensor data interfaces with the MDVR. The number and type of hard disk drives in the MSA is configured to provide sufficient storage for a configurable time up to 90 days (or more), covering all duty cycles within that configurable time span. The MDVR would also be configured with a rugged storage component such as a FLASH disk drive or automotive-grade hard disk drive of sufficient minimum capacity to record all data captured during a minimum of one or more duty cycles. During normal operation, the non-rugged commercial hard disk drives would be maintained in a non-operating state. In a non-operating state, the non-rugged storage devices consume little or no power, generate little or no heat and can survive environmental conditions that are comparable to the operating specifications of the rugged storage device. 
         [0008]    Again, during normal operation the MDVR would capture video, audio, and meta-data creating the necessary integrated data files and storing the information on the rugged storage device internal to the MDVR. The command and control software modules would monitor the system to determine if the vehicle has returned to an idle state or a holding location, and the environmental sensor signals are below pre-set threshold limits for permissible operating conditions. When the enhanced embedded software modules have determined that the vehicle meets these conditions they apply power to the MSA and transfer data files from the rugged storage device in the MDVR to the non-ruggedized disk drives within the MSA. 
         [0009]    During the transfer process, the command and control software would add additional meta-data to the files as they are transferred to an enhanced embedded database embodied within the MSA disk drives with location file pointers enabling the searching of files and file meta-data even during periods when the MSA is not operating. If the vehicle leaves an idle state or the environment on the vehicle becomes unsuitable for the operation of the MSA, the command and control software within the MDVR can cease file transfer operations, power down the MSA and continue storing subsequent data on the rugged storage component within the MDVR. 
         [0010]    The system also may include additional software command and control components to perform file transfers from rugged storage to the MSA based upon schedule or environment conditions, as the result of a learning algorithm, or perform incremental file transfers during shorter idle times (such as a traffic light or traffic tie-up). 
         [0011]    The present invention is an elegant solution to the problems of providing sufficient storage for the collection of critical data in a rugged vehicle environment and in a cost effective manner. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0012]      FIG. 1 : System Block Diagram 
           [0013]      FIG. 2 : State Diagram for Process 
           [0014]      FIG. 3 : Process Flow Diagram 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]    The present invention captures a systemic ability to provide a multi-cycle, where a cycle is defined as one operating day and may be up to 23 hours, data storage capability for video, audio, and metadata ( 100 ,  102 ,  104 ) that is captured by a vehicle mounted digital video recordation system  110 . This invention allows the system to by-pass the temperature, shock, and vibration limits on inexpensive storage devices and device arrays and use them to store data in a rugged environment for later retrieval as required. 
         [0016]    The preferred embodiment includes a Mobile Digital Video Recorder (MDVR)  110  system comprising one or more cameras, one or more microphones, data inputs from sensors  132 , data connections to embedded vehicle sensors, rugged storage  112  such as automotive-grade hard disk drives or FLASH storage, a control microprocessor  115 , and software modules to control the system ( 113 ,  114 ), store and retrieve data, and manage connectivity to components and communications channels outside of the MDVR  110 . In the preferred embodiment the MDVR  110  is connected via a high speed communication interface  134 , such as External Serial Advanced Technology Attachment (SATA), Universal Serial Bus (USB), or IEEE 1394, a power connection  130 , and a sensor data communication pathway  132  to a Mobile Storage Array (MSA)  120  comprising a suite of sensors  125 , such as power, temperature, shock, and vibration sensors, software modules for communication and control, power, interface and data connections to the MDVR ( 130 ,  132 ,  134 ), and sufficient inexpensive storage to provide sufficient storage for a configurable operation time of 90 days or more. For an operational period of 90 days, for example, the MSA would be configured with four 3.5″, 750 Gigabit SATA drives ( 121 - 124 ). 
         [0017]    In normal operation mode the MDVR  110  begins an operating cycle upon sensing that the vehicle ignition switch is engaged  300 , turning the vehicle on. In an initial state, the MDVR  110  powers up its internal rugged storage component  112  and the MSA  120  is in a non-operating, locked condition. In this state, both the rugged storage device  112  within the MDVR  110  and the inexpensive, non-ruggedized storage devices ( 121 - 124 ) within the MSA  120  meet the requirements for temperature, shock, and vibration required for an in-vehicle mounted system. As the vehicle begins a duty cycle  305  the MDVR  110  enters a record and store state in which video, audio, and metadata are captured during the operation of the vehicle and stored  310  into the operational rugged drive  112  within the MDVR  110 . In addition, an MDVR control software  114  module builds a metadata database file  315  within the ruggedized storage device  112  that contains a continually updated list of file pointers to all data files within the rugged storage device. 
         [0018]    At the end of an operation duty cycle, the vehicle returns to the depot or parking area where the vehicle is normally stored during the times between duty cycles. The MDVR  110  senses the ignition being turned to the off position  320  and uses this action as the trigger to mark the end of the duty cycle. The MDVR  110  then communicates with the MSA  120  to retrieve temperature, vibration, and shock sensor data from the sensors  132  in the MSA  120 . If each of these parameters are below previously established threshold levels  330 , as stored within the MDVA processor memory  115 , the MDVR control software  114  determines that there will be no damage to the non-ruggedized storage within the MSA  120  if the drives are operational. The MDVA  110  then supplies power to the non-ruggedized storage array  350 . 
         [0019]    In the preferred embodiment, with the non-ruggedized storage array powered up  350  the system begins transferring captured data files  355  from the MDVR rugged storage drive  112  as well as the metadata database  360  containing the file pointers for all of the data files captured. The high speed data interface  134  (SATA, USB, or 1394) is capable of transferring data from the rugged storage device to the non-rugged storage drives at a rate from 1 gigabyte up to 4 gigabytes per minute. During the process of transferring the data files, the signals from the temperature, shock, and vibration sensors within the MSA  120  are continually monitored  345  by the monitoring software module within the MDVR  113 . If the output from the sensors exceeds the preset threshold values  365  stored within the MDVR processor memory  114 , the file transfer is brought to an orderly stop. A pointer is maintained within the processor memory identifying the position within the rugged storage medium at which the data transfer was stopped. The MDVR control software module  113  then powers down the MSA  120 , allowing the non-ruggedized storage devices ( 121 - 124 ) to return to a state within which the non-ruggedized storage devices ( 121 - 124 ) are resistant to temperature, vibration, and shock levels as before. 
         [0020]    If, instead, the signals from the temperature, shock, and vibration sensors  132  within the MSA  120  remain below the preset threshold limit values stored within the MDVR processor memory  115 , the MSA storage devices ( 121 - 124 ) remain powered-up and the MDVR control software  113  continues to download captured data files  355  and the database of file pointers  360  until all data has been transferred to the MSA  120 . The MDVR control software module  113  then powers down the MSA  120 , returning the non-ruggedized storage devices ( 121 - 124 ) to their initial state. 
         [0021]    The vehicle mounted system is now ready for another duty cycle for the vehicle. This process repeats until the system managers at a permanent data storage facility are prepared to transfer the data files and metadata database of file pointers from the vehicle on-board MSA  120  to a permanent data storage facility where the data will be stored for future evidentiary and analysis needs. 
         [0022]    The preferred embodiment is only one of a number of scenarios under which the instant invention may be configured to securely store data files and data file pointer in the inexpensive non-ruggedized MSA storage devices ( 121 - 124 ). In another embodiment, the data and data file pointers may be retrieved from the ruggedized storage  112  within the MDVR  110  based upon a scheduled time. In this embodiment, regardless of whether the vehicle has returned to a parking facility or not, the MDVR control software  113  would, on a pre-set scheduled time, check the MSA sensors  125  for temperature, shock, and vibration sensor signal levels  132 . If the signal levels do not exceed the pre-set threshold levels, the MDVR control software module  113  would power-up the storage devices ( 121 - 124 ) within the MSA  120  and perform file  355  and file pointer  360  data transfer actions. The MDVR control software  113  continuously monitors the temperature, shock, and vibration sensor signal levels. If the sensor signal levels remain below the threshold levels, the MDVR  110  continues file  355  and file pointer  360  data transfer until all files have been transferred to the MSA  120 . The MDVR control software  113  then powers down the MSA storage devices ( 121 - 124 ) until the next scheduled data transfer time point. If the sensor signal levels exceed the acceptable threshold signal levels, the MDVR control software  113  discontinues the file and file pointer data transfer and powers down the MSA storage devices ( 121 - 124 ) until the next scheduled data transfer time point. 
         [0023]    In another embodiment, the MDVR control software module  113  continuously monitors the temperature, shock, and vibration sensor signals  345  anytime the vehicle is in a stopped or idle state. If the signal levels do not exceed the pre-set threshold levels, the MDVR control software module  113  would power-up the storage devices ( 121 - 124 ) within the MSA  120  and perform file  355  and file pointer  360  data transfer actions until all file and file pointer data is transferred to the MSA  120  or until the vehicle is no longer in a stopped or idle state. In this fashion the data files and file pointers are incrementally added to the MSA storage devices ( 121 - 124 ) during each duty cycle of the vehicle. 
         [0024]    The MDVR control software module  113  may also contain a learning module such that the control software is able to perform predictive analysis of the vehicle duty cycle. This predictive analysis software module learns when, within the vehicle duty cycle, there are stopped, idle, and parked times during which the MDVR control software  113  may assume, with a high degree of confidence, that the temperature, shock, and vibration sensor signals are below the threshold levels for theses sensors and may then power up the MSA storage drives ( 121 - 124 ), perform file and file pointer data activity, and power down the MSA storage drives ( 121 - 124 ) during the predicted window of time that the vehicle is stopped, idle or parked, and the sensor signals are below the signal threshold levels. 
         [0025]    The embodiments enumerated within this document are not intended to be comprehensive of all possible embodiments of the instant invention. The invention is not limited to the embodiments recited herein which are used to illustrate the preferred embodiments for operation of the invention. 
         [0026]    While this invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.