Systems and methods of locating weapon fire incidents using measurements/data from acoustic, optical, seismic, and/or other sensors
View Patent ↗Systems and methods are disclosed for locating a weapon fire incident such as an acoustic transient from a gunshot, explosion, weapons launch, etc. In one exemplary implementation, there is provided a method of locating the incident from a combination of propagation phenomena including a discharge time of the weapon fire incident. Moreover, the method may include obtaining a first propagation parameter of the incident from one or more first sensors, obtaining the discharge time from another sensor, and processing the data to determine a location using a common time basis among sensor measurements. According to further exemplary implementations, the discharge time may include a transient event that has a different propagation velocity than that of sound in the atmosphere.
1. A method of locating a weapon fire incident, the method comprising:
obtaining a first propagation parameter of the weapon fire incident from one or more first sensors, wherein each first sensor includes an acoustic sensing element, wherein the propagation parameter includes a first arrival time of a first signal from the weapon fire incident, and wherein the first signal's propagation velocity is the speed of sound through air;
obtaining a second arrival time of a second signal based on the weapon fire incident from a second, ground-coupled sensor, wherein the second sensor includes a sensing element that measures the discharge time as a function of an impulse of the weapon fire incident received through the ground and data regarding a velocity of the second signal propagating at the speed of sound through the ground;
processing first sensor data from the one or more first sensors along with second sensor data from the second sensor using a relative time base between sensors;
determining a location of the weapon fire incident as a function of the first arrival time, the second arrival time, and the propagation velocities of the first signal and the second signal, wherein a minimization technique comprising a least squares routine is used in determining the location;
providing the location of the weapon fire incident as an output;
wherein an acoustic-based calculation of the location of the weapon fire incident is augmented by one or more range estimation or calculation techniques;
wherein the range estimation techniques includes use of a seismic sensor used to identify a muzzle blast, or a weapon-fire or a weapon-launch;
wherein the location is determined via an algorithm that includes determining intersection(s) between first data representative of the first propagation parameter and second data representative of the second propagation parameter;
wherein the sensors include two or more of: (a) 2 sensors having first propagation parameter sensing elements; (b) a single bearing sensor with multiple first propagation parameter sensing elements; and/or (c) a single t 0 (discharge time) sensor;
wherein the acoustic-based calculation is based on triangulation using the difference in time of arrival of acoustic transients at three or more sensor locations.
2. The method of claim 1 wherein the impulse through the ground propagates at either P-wave velocity or S-wave velocity.