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Line Safety Monitor Basic outline,
United States Patent 6,377,184
Minker April 23, 2002

In keeping with modern trends toward the utilization of Commercial Off The Shelf ( COTS ) systems integration, The Line Safety Monitor is developed completely around readily available technologies, and is operated by virtually any common P.C. type computing system. Careful attention is paid to minimizing the number of specialized and custom manufactured mechanical or physical components. With a software package that is Windows compatible, the system runs with a point and click simplicity. With comparison and response analyzation interaction provided by the System Operator, Chief Engineer, or other station personnel. The Line Safety Monitor ( LSM ) allows hands on decisions to be made in the continuing education of the system.

A newly initialized Monitor System is shipped with a complete hardware package which is custom derived for each application. While using a menu of standardized components, each installation will use a varying number of actual sensor and cabling groups. This cost efficient, minimized cost. customized package of components is accompanied by the standard Software grouping which is supplied via CD ROM. Within the package is the primary operating system, and initial master library of data that provides the basis of acoustic and gas purity comparisons from which the LSM is educated.

Education of the newly initialized LSM is the key to the growth and knowledge of the unit. The following paragraphs outline the basis by which each installation of The LSM becomes self aware as a stand alone system, which is capable of sharing its information with the Factory based Host System in a give and take basis. This information exchange is a key component to developing continuingly expanding comparative data bases accessible via E-Mail, or other Modem activities in a localized, or regionalized basis.

The Line Safety Monitor is an acoustic and gas purity tracking system which is truly self aware and continuously self educating. Interaction by the Operator allows for visual and acoustic heterodyned audible analysis of all events in the acoustic mode. Comparison in a library look up basis to existing files is continuously performed and checked for pattern matches on a user selectable ratio from one of the many control screens in the Windows format. 
Assignment of all newly acquired events is approved by the operator and is integrated in to the future operation of the unit.

Operator control of visual and acoustic analysis, external communication, alarm level assignment, and external interface abilities for warning and Transmitter control are a part of the system.

During the normal course of the monitoring activities, the LSM catalogs all acoustic events in to three groups. Alarm level three events are logged and saved for analysis at a later time by the operator as " curious " but not within any deliberately non-permissive pattern match. Alarm level two acoustic, and gas purity change events are similarly logged, however theses are accompanied by a dial out or signal to the operator warning of a similarity in an acoustic pattern match to a non-permissive signature, or gas purity change. Alarm level one events are similarly logged and are accompanied by a programmable system shut down, and a dial out or signal to the operator that the LSM is active and that a definitive acoustic signature, and or gas purity problem has been found. All combinations of function are available in the alarm screen for maximum user integration and control. Events captured by the LSM that are of no significant match are discarded.

To assist the LSM in its continuing education, the operator is presented with a visual display of the recorded acoustic events from all three alarm levels in the alarm log. This visual display of the log is provided to reference the captured event wave forms and the accompanying translated acoustic signatures. These two files assist the operator in evaluating the viability of entering a new signature in to the data base as an " Add " to the non-volatile library. The acoustic signature library is shipped as a non-volatile set which may be modified by password protection. Admission, deletion, and modification are at the user's discretion.

Diagnostics are an integral part of the LSM package. At start up and periodically through the operating day, the system interrogates the sensor and data packages to verify that all systems are operational. These results are continuously displayed and are linked to the assignable alarm levels as an indicator of a malfunction.

Expansion and system re-use are a simple change of parameter. The system may be re-initialized as a modification to include changes in sensor orientations, locations, identification, English descriptors, and sensor quantities. These fields simply allow the user to re-configure the system with no danger of discarding any learned information. All changes require a password level authorization and verification of any destructive changes are verified by typed entry.

The LSM utilizes a series of strategically placed Ultrasonic detectors. These detectors are tuned to monitor the acoustic signatures of noises contained within a Transmission System in an audio band extending from 20 KHz to 40 KHz. This recovered audio is digitized at each sensor and shipped via RS-232, Fiber, or other similar serial means to the Master Processing Unit where each signal is decoded and compared to a master library of permissible and not permissible sounds.

These units are inserted in to gas block style frames at 200 to 400 foot intervals. The gas block style frames are drilled to facilitate acoustic coupling of the sensor to the line cavity area. Acoustic coupling must be bidirectionally linear. Acoustic signatures are collected by a precision electret style condenser microphone having a predictable acoustic response. This acoustic analog signature is digitized at a high bit and sample rate. This digitized signal is encoded with the sensor location number and transmitted via high speed serial mode of twisted pair, fiber, or coaxial conductor to the Master Processing Unit.

The LSM Master Processor Unit is a library comparator unit. This unit decodes the high speed bit stream and analyzes each listening unit and gas sensor in a real time mode. These continuous signatures are compared in a rolling time window to a library of cataloged sounds. This library contains a vast number of Ultrasonic byproduct events which are meticulously recorded and digitized for this unit. The library would compare the Ultrasonic signatures of acceptable noises such a line scraping, mild impacts, spring resonance, and pressurizing gas orifice noise to those of the acceptable parameter library files. Noises that would be filed and cataloged as not permitted are those attributed with arcing of any type. Single discharges, prolonged scraping contacts generating arcing, and corona discharge are not permitted signatures. 
Upon receipt of any recognized and not permitted noise, the LSM will give an alarm condition indications. Among these indications would be the sensor location, and library file noise signature number. Acoustic playback of translated signatures would be optional. Certain noises will have the ability to give various levels of alarm indication. A long term memory of alarm condition is outputable to any terminal.

The gas purity sensing companion portion of the LSM system is specifically designed to monitor the condition of the pressurized environment within the sealed system. Changes in the quality and purity of the selected gay type are continuously monitored and the quality is displayed as a graph by the computer. Any deviations in the quality of the environment are logged and assigned to the alarm list. Gas purity violations are automatically listed as an automatic level 2 alarm which is designed to call for assistance and interpretation immediately upon discovery.

Communications with the primary LSM PC are accomplished via any standard modem, or in advanced systems an IP address. This modem or other connection allows for screen emulation in the remote mode. While speed is somewhat diminished, the entire windows screen environment may be accessed via the Modem connection which will allow remote down loading of files, wave tables, wave forms, and all active and set up screen from a remote location. This feature allows the user to continue to utilize older existing computing equipment which keeps the number of superior machines to a minimum, while keeping flexibility and operational control at a maximum.

The LSM will have sufficient memory to support unattended operation of alarm events for several thousand events. Output of the alarm events is be compatible with many remote control systems on the market today. Interface would also be supplied to mate with any standard Hayes compatible dial up auto answer modem system for interrogation independently in a ring or forced carrier mode.

Each system sensor is comprised of a dual input system. Unit 1 is acoustic. This device listens to the audio spectrum from the low frequency cut off of the transducer to about 20 KC. This continuous stream of analog audio is digitized ( initially at 16 bit resolution ) and placed in to a packet which contains other data.

Sensor unit 2 is a gas product sensor. This sensor is a specialized unit which looks for products of combustion, acid vapors and or, monoxides. A more simple Nitrogen type system may be used. This sensor feeds a linear gas comparitor. This linear quality word is embedded in to the packet sent to the processor
The packet of data from the individual sensor locations contains a two digit numeric or alpha identifier, the gas product quality word, and the 50 millisecond audio packets.
This sensor package is field programmable for I.D. and operates on 48 V.A.C. for electrical surge event isolation and immunity. For simplicity, the sensor system quality word will also contain the sensor I.D. number.

The package is weather tight in a gasketed and hinged sealed box with weather tight connectors. ( 2 power, in out ) ( acoustic transducer ) ( gas sensor ).

The sensor installation package is comprised of a specially milled gas barrier type flange for the appropriate size of line. These flanges are milled to accommodate the installation of the acoustic and gas product barrels. The insulator and bullet ( where applicable ) are drilled as to promote passage of gasses. These units are easily installed in to existing systems with the flanged sensor unit and a new longer bolts kit. Recommended spacing is every 200 to 400 feet.


IBM compatible or clone Personal Computer
486 or higher
4 Meg Ram or higher
1 Gig hard drive or larger
VGA monitor or higher
Mouse or pointer
Sound card with speakers 
CD ROM ( optional )
Modem ( speed optional )
2 com ports
Epson compatible printer

An external I/O is provided with 2 closure contact sets which is operated from a selectable com port . This I/O gives indications of primary and secondary alarm conditions within the program parameters. These closures are available as normally open or closed, non latching, or latching. ( software programmable ) This unit is provided as a DB-9 male plug with no tail, to which the relay package is attached. The relay package may be extended via a user provided com port extension cable. A quick connect screw barrier strip provides access to the closures. This unit should be rated for 50 V.D.C. at 1 Ampere. The interface will draw operating voltage from the computer bus supply.



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