Systems and methods of identifying/locating weapon fire including aerial deployment

• US 7,755,495 B2
• Filed: 10/30/2007
• Issued: 07/13/2010
• Est. Priority Date: 01/24/2003
• Status: Expired due to Term

• Current Assignee: Shotspotter Incorporated
• Original Assignee: Shotspotter Incorporated
• Inventors: Fisher, Ken, Holmes, Fred H., Baxter, Kevin
• Primary Examiner(s): Nguyen; Phung
• Application Number:
  US11/981,757
• Publication Number:
  US 20080267013A1
• Time in Patent Office: 987 Days
• Field of Search: 340/573.1, 340/426.19, 340/506, 340/539.13, 340/995.28, 340/691.6, 340/825.36, 340/521, 367/127
• US Class Current: 340/573.1
• CPC Class Codes: F41H 13/00 Means of attack or defence not otherwise provided for details of radar or sonar systems G01S7/00
• CPC Class Codes: G01S 5/18 using ultrasonic, sonic, or infrasonic waves
• CPC Class Codes: G01S 5/22 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/28 takes precedence
• CPC Class Codes: Y10S 367/906 Airborne shock-wave detection

Abstract

Systems and methods are disclosed for locating the source of an acoustic event. In one exemplary implementation, there is provided a method of locating the source of an acoustic event by receiving/processing information from at least three sensors aerially deployed across an area to be monitored, wherein each of the at sensors has a microphone for detecting the acoustic event and a known location, the at least three aerial deployed sensors are networked, and time of arrival processing of the acoustic event is performed. In further exemplary implementations, an approximate location of the source of the acoustic event may be determined as a function of arrival time and sensor location data.

Claims

1. A method of processing data associated with acoustic weapon fire events, the method comprising:

performing aerial deployment of at least three aerial sensors across an area to be monitored, wherein each of the at least three sensors comprises a microphone for detecting a weapon fire event, and wherein the location of each of the at least three sensors is known;

networking the at least three aerial sensors via a network;

processing signals communicated over the network from one or more sensors that detect the weapon fire event, wherein the signals include time of arrival data as to when a muzzle blast from with the weapon fire event was detected at the one or more sensors, with each time of arrival being obtained from a synchronized or absolute time source associated with a sensor that detected the weapon fire event; and

determining an approximate location of a source of the weapon fire event as a function of arrival time and sensor location data;

wherein the approximate location of the source of the weapon fire event is determined as a function of one or more of temperature, relative humidity, and/or air pressure.

2. The method of claim 1 further comprising processing one or more of temperature, relative humidity, and/or air pressure data obtained via a wireless communication receiver associated with at least one sensor.

3. The method of claim 1 further comprising determining a location of a sensor via detection equipment, associated with at least one sensor, that detects a distance to a ground position.

4. The method of claim 1 wherein the approximate location of the source of the weapon fire event is determined in connection with a process that includes transmitting arrival time data from the sensors to a host computer.

5. The method of claim 4 wherein transmitting arrival time data from the sensors to the host computer includes transmitting arrival time data from each of the sensors to a relay, and transmitting the arrival time data from the relay to the host computer.

6. The method of claim 1 wherein muzzle blast time of arrival data from the sensors is used in determining direction from a sensor location towards the source of the weapon fire event.

7. A method of processing data associated with acoustic weapon fire events, the method comprising:

processing data from at least three aerial sensors deployed across an area to be monitored, wherein each of the at least three sensors comprises a microphone for detecting a weapon fire event, and wherein the location of each of the at least three sensors is known;

networking the at least three aerial sensors via a network, including processing signals communicated over the network from one or more sensors that detect the weapon fire event, wherein the signals include time of arrival data as to when a muzzle blast from the weapon fire event was detected at the one or more sensors, with each time of arrival being obtained from a synchronized or absolute time source associated with a sensor that detected the weapon fire event; and

determining an approximate location of a source of the weapon fire event as a function of arrival time and sensor location data;

wherein the approximate location of the source of the weapon fire event is determined as a function of one or more of temperature, relative humidity, and/or air pressure.

8. The method of claim 7 further comprising processing one or more of temperature, relative humidity, and/or air pressure data via a wireless communication receiver associated with at least one sensor.

9. The method of claim 7 wherein one or more of the aerial sensors are associated with detection equipment for measuring temperature, relative humidity, and/or air pressure.

10. The method of claim 7 further comprising determining a location of a sensor via detection equipment, associated with at least one sensor, that detects distance to a ground position.

11. The method of claim 7 wherein the approximate location of the source of the weapon fire event is determined in connection with a process that includes transmitting arrival time data from the sensors to a host computer.

12. The method of claim 11 wherein transmitting arrival time data from the sensors to the host computer includes transmitting arrival time data from each of the sensors to a relay, and transmitting the arrival time data from the relay to the host computer.

13. The method of claim 11 wherein muzzle blast time of arrival data from the sensors is used in determining direction from a sensor location towards the source of the weapon fire event.

14. The method of claim 7 wherein one or more of the aerial sensors includes a GPS receiver.

15. The method of claim 14 wherein muzzle blast time of arrival data from the sensors is used in determining direction from a sensor location towards the source of the weapon fire event.

16. The method of claim 7 wherein data processed is data from sensors aerially deployed from an airplane.

17. The method of claim 7 wherein muzzle blast time of arrival data from the sensors is used in determining direction from a sensor location towards the source of the weapon fire event.

18. The method of claim 7 wherein determination of the approximate location of the source of the weapon fire event includes iterative calculations of expanding spheres.

19. The method of claim 7 wherein the aerially deployed sensors include solar cells for powering or recharging a sensor battery.

20. A system for processing data associated with acoustic weapon fire events, the system comprising:

at least three aerial sensors, each sensor of the at least three aerial sensors comprising;

a microphone capable of producing a signal in response to weapon fire event signal received at the sensor;

a processing device communicatively coupled to the microphone;

an absolute or synchronized time source communicatively coupled to the processing device; and

a networking interface communicatively coupled to the processing device; and

a processor, wherein the processor is communicatively coupled to each of the aerial sensors via the network interface of each sensor; and

wherein, in association with detection of a weapon fire event by at least one of the at least three aerial deployed sensors, the processor is configured to;

process signals from one or more sensors that detect the weapon fire event, wherein the signals include time of arrival data as to when a muzzle blast from the weapon fire event was detected at the one or more sensors, with each time of arrival being obtained from a synchronized or absolute time source associated with a sensor that detected the weapon fire event; and

determine an approximate location of a source of the weapon fire event as a function of arrival time and sensor location data;

wherein the approximate location of the source of the weapon fire event is determined as a function of one or more of temperature, relative humidity, and/or air pressure.

21. The system of claim 20 wherein one or more of the aerial sensor includes a wireless communication receiver that processes one or more of temperature, relative humidity, and/or air pressure data.

22. The system of claim 20 further comprising a component that determines a location of a sensor via detection equipment, associated with at least one sensor, that detects a distance to a ground position.

23. The system of claim 20 wherein the processor is further configured to determine the approximate location of the source of the weapon fire event in connection with a process that includes transmitting arrival time data from the sensors to a host computer.

24. The system of claim 23 wherein transmitting arrival time data from the sensors to the host computer includes transmitting arrival time data from each of the sensors to a relay, and transmitting the arrival time data from the relay to the host computer.

25. The system of claim 20 wherein muzzle blast time of arrival data from the sensors is used in determining direction from a sensor location towards the source of the weapon fire event.