PATENT WITHDRAWN
Highly portable system for acoustic event detection
PATENT WITHDRAWN
Highly portable system for acoustic event detection
Patent 7289030 Issued on October 30, 2007. Estimated Expiration Date: 
January 20, 2025. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
January 20, 2025. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesSonic monitoring method and apparatus Gunshot detector System for effective control of urban environment security Method and a system for locating a firearm on the basis of acoustic detection Automatic real-time gunshot locator and display system Personal emergency, safety warning system and method Network communication techniques for security surveillance and safety system Ground based security surveillance system for aircraft and other commercial vehicles Patent #: 6545601 InventorsAssigneeApplicationNo. 10905788 filed on 01/20/2005US Classes:340/573.1, Human or animal340/691.6, Information display367/127, With time interval measuring means340/524, Condition position indicator381/56, MONITORING OF SOUND367/124, By combining or comparing signals340/539.13, Tracking location (e.g., GPS, etc.)348/143, Observation of or from a specific location (e.g., surveillance)340/521Plural diverse conditionsExaminersPrimary: Nguyen, PhongInternational ClassG08B 23/00DescriptionBACKGROUND OF THE INVENTION The present invention relates to a system and method for detecting and locating an acoustic event. More particularly, but not by way of limitation, the present invention provides a highly portable gunshot detection system. Gunfire and sniper detection systems are generally known in the art. Such systems can be broadly grouped into three categories: systems which pinpoint the precise location of the source of gunfire; azimuthal sensors which provide an indicationof the radial direction to the source of gunfire; and proximity sensors which merely provide an indication that nearby gunfire was detected. While such systems have been demonstrated to perform in both law enforcement and military applications, theentire field is presently an emerging technology. In many large cities, gun-related violence has become a plague of epidemic proportions. Urban gunfire, whether crime-related or celebratory in nature, results in thousands of deaths per year in the United States alone. Gunfire location systems,such as those installed in the Redwood City, Calif., Glendale, Ariz., Willowbrook, Calif., City of Industry, Calif., and Charleston, S.C. areas, have proven to be effective in reducing law enforcement response time to detected gunfire, apprehendingcriminals, collecting evidence, and reducing the occurrence of celebratory gunfire. One such system is described in U.S. Pat. No. 5,973,998, issued to Showen, et al., which is incorporated herein by reference. Showen, et al. discloses a system wherein sensors are placed at a density of roughly six to ten sensors per square mile. Audio information is sent to a computer at a central location and processed to: detect a gunshot; determine a time ofarrival for the gunshot at each sensor; and calculate a location of the shooter from the differences in the times of arrival at three or more sensors. Showen, et al. takes advantage of the long propagation distance of gunfire to place sensors in arelatively sparse array so that only a few of the sensors can detect the gunfire. This permits the processor to ignore impulsive events which only reach one sensor--a concept called "spatial filtering." This concept of spatial filtering radicallyreduces the sensor density compared to predecessor systems, which require as many as 80 sensors per square mile. Another gunshot location system is described in co-pending U.S. patent application Ser. No. 10/248,511 by Patterson, et al., filed Jan. 24, 2003, which is incorporated herein by reference. Patterson, et al., discloses a system wherein audioinformation is processed within each sensor to detect a gunshot and determine a time of arrival at the sensor. Time of arrival information, as determined from a synchronized clock, is then transmitted wirelessly by each sensor to a computer at acentralized location where a location of the shooter is calculated in the same manner as in the Showen, et al. system. As yet, azimuthal systems have not been as widely accepted as, for example, the Showen, et al. system. Azimuthal sensors typically employ one or more closely-spaced sensors, where each sensor includes several microphones arranged in a smallgeometric array. A radial direction can be determined by measuring the differences in arrival times at the various microphones at a particular sensor. Presently such systems suffer from somewhat limited accuracy in the determination of the radialangle, which in turn, translates into significant errors in the positional accuracy when a location is found by finding the intersection of two or more radial lines, from corresponding sensors, directed toward the shooter. Since errors in the radialangle result in ever increasing positional error as the distance from the sensor to the source increases, the reported position will be especially suspect toward the outer limits of the sensors' range. A concern unaddressed by the present art is a portable system for gunshot detection and location. In particular, an array of portable sensors in combination with individual display devices and a portable server. Patterson, et al. discloses aportable sensor having a belt clip but fails to disclose a portable system. For example, in a military environment, merely detecting a gunshot and providing a source location at a central location is ineffective. A soldier must be provided the source location in a meaningful manner and in a meaningful time frame toreturn fire and/or take cover or the system has failed to attain its goal. Similar issues arise in law enforcement applications during tactical operations such as during sniper incidents, hostage situations, and the like. Rapid deployment is only partially addressed by a wireless sensor. Infrastructure forcommunication with a server and providing meaningful information to the people who need the information requires more than a mere portable sensor. Some existing azimuthal sensors are suitable for rapid placement but are not actually portable in the sense that individual soldiers or officers cannot wear or carry the sensors operationally and there is no provision for instantaneous display tothe individual solder that is actually being fired upon. It is thus an object of the present invention to provide a highly portable system for the detection and location of gunfire wherein all components of the system are portable and the system provides near immediate information directly toindividuals who are directly in the line of fire. SUMMARY OF THE INVENTION The present invention provides a highly portable system for detecting and locating the source of gunfire. In a preferred embodiment, the inventive system includes: a plurality of man wearable acoustic sensors, each such sensor having a displaydevice associated therewith; a host processor for receiving information concerning acoustic events and calculating a source location based on such information; and a communication network for bidirectional communication between sensors and the hostprocessor. For purposes of this disclosure, the term "man wearable" refers to a sensor which is integrated into a piece of equipment normally carried by a soldier, integrated into an article of clothing, or attached to a piece of equipment or readilyattachable to the soldier or an article of clothing via a secure mount such as a latch, loop-and-hook strap, and so on. In one preferred embodiment, the sensor and the display are separate but associated so that information provided on the display is relevant based on the position of its associated sensor. In one variation, the sensor is incorporated into bodyarmor and consequently, a soldier is burdened with one less piece of equipment. In another preferred embodiment, the sensor and display are integrated into a common housing such that a single unit is maintained in easy view of the soldier. In one variation, the sensor is incorporated into a helmet. A drop down ocularprovides information about the soldier's position and shooter location. In still another preferred embodiment, the host processor is incorporated into a piece of equipment, or article of clothing, used by a squad leader providing location fixes for acoustic events, administrative overhead of the system, andcommunication with command centers and other squads. Further objects, features, and advantages of the present invention will be apparent to those skilled in the art upon examining the accompanying drawings and upon reading the following description of the preferred embodiments. BRIEFDESCRIPTION OF THE DRAWINGS FIG. 1 depicts a preferred configuration of the inventive gunshot detection system. FIG. 2 provides a block diagram of a wireless sensor for use in the inventive gunshot detection system. FIG. 3 depicts a preferred embodiment of a sensor or host as incorporated in a wristwatch housing. FIG. 4 depicts a preferred embodiment of a sensor or host as incorporated in a helmet. FIG. 5 depicts a preferred embodiment of a shoulder mounted sensor or host. FIG. 6 depicts a preferred embodiment of a gun mounted sensor or host. FIG. 7 depicts a preferred embodiment of a sensor or host incorporated in a walkie-talkie. FIG. 8 depicts a preferred embodiment of a sensor or host as incorporated into body armor. DESCRIPTION OF THE PREFERRED EMBODIMENTS Before explaining the present invention in detail, it is important to understand that the invention is not limited in its application to the details of the construction illustrated and the steps described herein. The invention is capable ofother embodiments and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation. Referring now to the drawings, wherein like reference numerals indicate the same parts throughout the several views, a representative gunshot detection system 100 is shown in its general environment in FIG. 1. In a preferred embodiment, aplurality of sensors 102-106 are dispersed over a monitored area. Sensors 102-106 may be any combination fixed sensors and/or portable sensors. Preferably, fixed sensors are placed to have a relatively unobstructed acoustic view around in the immediatearea. By way of example and not limitation, suitable sites for fixed sensors include: placed atop a building; placed atop utility or light poles; on towers, etc. Typically sensors 102-106 communicate through a communication network 108 with acentralized processor 110 wherein information concerning acoustic events is processed to provide details of the event, such as the source location of a gunshot, time of the gunshot, the number of detected gunshots, the type of event, and the like. Itshould be noted that sensors 102-106 may be any combination of wired or wireless sensors, that communications paths 112-116 may carry either analog or digital signals, and that network 108 may comprise any combination of sub-networks, such as, by way ofexample and not limitation: a telephone network; the internet; a private computer network; a wireless network, or even a collection of dedicated wires routed to the sensor array. To ensure that the monitored area is relevant, in a military environment it may be preferable that sensors 102-106 are man-wearable. In such a system, the host computer 110 and display devices 120 would likely be carried by a squad leader. Other ancillary display devices are preferably provided with each man-wearable sensors to allow the soldier to quickly return fire, or at least take cover. In such a system, other ancillary systems may use data collected by the gunshot location systemas reported in real time, or near real time, to higher levels or command centers. Referring to FIG. 2, a preferred embodiment of sensor 102 includes: a microphone for receiving acoustic events; an amplifier 212 and possibly other signal conditioning circuitry; a processor 224, typically a digital signal processor, having ananalog to digital converter 218; a GPS receiver 226 and its associated antenna 216; and an interface 214 for communicating via a communication network. In practice, gunshots are received at microphone 210, the audio signal is conditioned by circuitry 212, digitized by A/D converter 218 and processed to detect gunshots in DSP 224. Upon detecting a gunshot, a time of arrival and sensor positionare obtained from GPS receiver 226 and transmitted to a host system via interface 214. As will be appreciated by those skilled in the art, in a law enforcement environment information about a detected acoustic event is typically output to a person of interest such as a police dispatcher or directly to individual officers, asthrough network 118 to display devices 120 or a computer console. When weapon 122 is fired, the muzzle blast reaches sensors 102-106 at different times based on the speed of sound and the distance between a sensor and the shooter. Whether the acousticinformation is processed at the sensor, or at computer 110, a time of arrival is determined for each sensor and the differences of the various times of arrival are processed to determine a location of the source of the gunshot. In response to thegunshot, information is provided at device 120. One preferred embodiment of a sensor 402 is shown in FIG. 3 wherein the sensor and display 416 are incorporated into a wristwatch housing 500. Preferably GPS and communication antennae are housed internally or incorporated in watchband 406. Buttons 424 allow scrolling through screens of information of display 416 or allow the mode of operation to be changed. Windscreen 404 reduces wind noise received by sensor 402 and protects the microphone (not shown) from minor impacts. In a preferredembodiment, sensor 402 has an exterior color which will blend well with the soldier's uniform and/or the environment. The wristwatch housing of FIG. 3 may alternatively house a host system and, as such, would typically be worn by a squad leader. In such a configuration, display 416 could be used to display the location of any soldier in the squad, historicaldetails, receive messages up and down the chain of command, as well as display current shooter information when the squad is fired upon. In addition, the wristwatch of FIG. 3 could be used as a user interface (e.g., display, user input, etc.) for alternate sensor embodiments described herein, such as when the sensor is incorporated into body armor or is shoulder-worn. Turning to FIG. 4, optionally the sensor can be mounted in helmet 700. In such a configuration the components are largely hidden by shell 702. Preferably if shell 702 is formed of a composite material, a GPS patch antenna or phased array islaminated directly in shell 702. Sensor 402 (e.g., flip-down visor or wristwatch) provides a display 416 for soldier location, shooter location when a gunshot is detected, messages from the squad leader, etc. Buttons 424 allow scrolling between screensand/or mode changes as the user desires. As with the wristwatch embodiment, helmet 700 may alternatively house the host processor, in which case visor 402 can be used to display administrative information, individual soldier positions, and the like, aswell as shooter location when the squad comes under fire. In another configuration, visor sensor 402 can be used to display information from other systems, as a night vision display, or even as a display for gunshot detection sensors incorporated intobody armor or otherwise worn by the soldier. FIG. 5 shows a gunshot detection sensor 710 in a shoulder mounted configuration. Windscreen 712 protects a microphone and preferably GPS and radio antennae. Housing 714 may be rounded to conform to the soldier's shoulder. Since sensor 710 isnot readily viewable by the soldier, it is contemplated that sensor 710 will associate with an external display such as headgear mounted display 716. Turning next to FIG. 6, sensor 602 may also be mounted to a rifle or other firearm 606. In a preferred embodiment, sensor 602 mounts proximate scope 600 for convenience of the soldier. Information is presented on display 608 and switches 610may be used to scroll through various screens and/or change operating modes of sensor 602. In one preferred embodiment, scope 600 includes a graphic display which overlays the image seen through ocular 604 such that targeting information is visuallyprovided in the soldier's scope as a target is sighted. Preferably the housing of sensor 602 is of a color and material to blend well with rifle 606 and has rounded corners so as not to catch on obstructions. Sensor 602 may also provide host functionsfor other sensors. Scope 600 may also be configured for night vision use. Referring next to FIG. 7, wherein is shown a walkie-talkie/acoustic sensor combination 620. Device 620 includes windscreen 622 for protecting a microphone and antennae for the GPS, radio, and sensor communication network. Display 624 providesdisplay of operating information for radio operations, GPS operation, and sensor operation. Buttons 626 and joystick 628 allow navigation through the various information and screens displayed on display 624. A push-to-talk button 630 provides controlof audio transmissions. As will be apparent to those skilled in the art, a single microphone can be used to monitor environmental sounds to detect gunshots and for receiving voice for walkie-talkie transmissions. Since device 620 can accommodate arelatively large display 624, device 620 is well suited for use as a host where more information, or simultaneous information may need to be displayed. Device 620 may also receive text messages or even images for output on display 624. FIG. 8 shows a sensor for a gunshot detection system integrated into body armor 800. The components of the sensor are largely hidden within body armor 800. Windscreen 802 protects the microphone while antennae for the GPS receiver andcommunication are internal to the vest 800. The circuitry for the sensor is preferably embedded within vest 800. Embodiment 800 is particularly well suited for use as a host node since there is considerable area for the added circuitry. Preferablybody armor 800 is used with a wristwatch display, helmet-mounted display, or rifle scope display. It should be noted that when a sensor, or host, is used with an external or associated display, as opposed to an integrated display, that a communication means is required between the sensor and the display. By way of example and not limitationsuitable communication means include: a digital radio link; infrared; wireless Ethernet; Bluetooth; and the like. Preferably suck a link is of minimal power and transmits intermittently to avoid detection by opposing forces. It should also be noted that while preferred embodiments of the present invention have been described in connection with gunshot location systems, the techniques for providing a convenient means for equipping a soldier or police officer with awearable gunshot detection sensor can be applied to other types of systems, such as those monitoring health conditions, environmental conditions, and the like. Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While presently preferred embodiments have been described for purposes of this disclosure,numerous changes and modifications will be apparent to those skilled in the art. Such changes and modifications are encompassed within the scope and spirit of this invention. * * * * * |
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