SYSTEMS AND METHODS ASSOCIATED WITH DETECTION OF INDOOR GUNFIRE

• US 20140327543A1
• Filed: 03/31/2014
• Published: 11/06/2014
• Est. Priority Date: 03/31/2013
• Status: Active Grant

• Current Assignee: Shotspotter Incorporated
• Original Assignee: Shotspotter Incorporated
• Inventors: SHOWEN, Robert, BELDOCK, James, STONE, Gregory, JOHNSON, Murphey, CALHOUN, Robert
• Granted Patent: US 9,240,114 B2
• Time in Patent Office: Days
• US Class Current: 340/540
• CPC Class Codes: G01S 5/18 using ultrasonic, sonic, or infrasonic waves
• CPC Class Codes: G08B 13/1672 using sonic detecting means, e.g. a microphone operating in the audio frequency range
• CPC Class Codes: G08B 17/08 Actuation involving the use of explosive means
• CPC Class Codes: G08B 29/183 Single detectors using dual technologies G08B13/1672, G08B13/2448, G08B13/2494 take precedence
• CPC Class Codes: G08B 29/188 Data fusion; cooperative systems, e.g. voting among different detectors

Abstract

Systems and methods are disclosed for reliably detecting gunfire in enclosed spaces having significant acoustic reverberation. Implementations are configured to quickly and reliably report the room or portion of a room where gunfire is located. Innovations herein may ensure low false alarm rate by thresholding, pattern recognition and/or detecting the muzzle optical flash. In some embodiments, a review center with trained personnel may evaluate the incident before reporting to local authorities. The indoor system can be incorporated into an outdoor gunshot location system to better protect a local area such as a campus or a transportation hub. Systems and methods herein may involve features and functionality associated with additional resources, such as intercoms, cellphones, and access control, to provide mitigation of harm in case of a shooting.

Claims

1. An indoor gunshot detection system comprising:

indoor sensors arranged to detect gunfire in a series of enclosed spaces having significant acoustic reverberation;

wherein sensors are constructed with microphones designed to detect high amplitude impulses between about 120 dB to about 160 dB from nearby gunfire;

one or more processing components and/or computer readable media configured to process potential gunshot data utilizing knowledge of particular sensor positions and designed to;

analyze impulses received by the indoor sensors

determine if the received impulses are gunfire, and

pass alerts to at least one of local authorities, persons at risk, or a central alert facility; and

at least one networking component constructed and arranged to transmit communications between the indoor acoustic sensors, the processing components and/or computer readable media, and computing devices that receive the alerts.

3. The system of claim 1, wherein a threshold on the acoustic impulse magnitude is reached before an alert is passed, in order to discard impulsive events too weak to be gunfire.

5. The system of claim 1, wherein the passing alerts comprises transmitting data to human reviewers of the data via the communication network, and wherein the data sent to the human reviewers comprise recorded impulsive sounds from the enclosed spaces and/or information defining a visual presentation of the acoustic waveforms.

6. The system of claim 5, wherein the sound data sent to the human reviewers comprise any distressed occupant sounds within the enclosed spaces where the putative event occurs.

7. The system of claim 1, wherein the one or more processing components and/or computer readable media are configured for processing an unknown impulse to determine whether or not the unknown impulse has a characteristic compatible with gunfire.

8. The system of claim 7 wherein the processing involves one or more of decay times and/or shapes corresponding to expected theoretical decay times and/or shapes which depend on a known size and acoustic treatment of the room.

9. The system of claim 7 wherein, when an entire decay curve cannot be processed due to saturation of the signal, a slope of the decay can be used instead of the decay time.

11. The system of claim 1, wherein the sensors include cameras that capture picture or video data, and wherein one or more pictures or videos, recorded by a camera starting at an instant of concern triggered by an impulsive sound, are transmitted to a central alert facility.

12. The system of claim 11, wherein the central alert facility performs additional processing.

13. The system of claim 12, wherein the additional processing comprises human review of the one or more pictures or videos.

82. The system of claim 1 wherein one or more of the sensors further include an IR detector to measure an optical flash of gunfire.

83. The system of claim 82, wherein impulses detected from the IR detectors and the microphones are compared against expected transit times across the room to give more confidence that detected impulses are actual gunfire.

84. The system of claim 82, wherein the processing components and/or computer readable media is configured to compare shape or amplitude of the acoustic and IR impulses with known weapon or firework characteristics, such that classification of the impulses as a known weapon or firework can be made.

85. The system of claim 82, wherein the processing components and/or computer readable media utilize differences in arrival times between the IR and acoustic impulses to:

determine distance between the sensor and potential gunfire incidents; and

compare the arrival time information against expected travel time across the room and discard potential incidents corresponding to distances greater than the room size.

86. The system of claim 1 wherein the processing components are further configured to process data collected from outdoor acoustic sensors disposed in areas adjacent to the series of enclosed spaces, such that shooting incidents transitioning between indoor areas and outdoor areas are detected.

87. The system of claim 1 wherein a room sensor uses two acoustic channels including a low gain channel and a high gain channel.

88. The system of claim 87 wherein the low gain channel records gunfire with little saturation, which is provided to the one or more processing components and/or computer readable media for automated analysis and triggering, and the high gain channel records human responses to the gunfire, which the system provides to human reviewers for analysis and verification of automatically triggered alerts.

2. (canceled)

4. (canceled)

10. (canceled)

14-81. -81. (canceled)