Raytheon Bbn Technologies Corp.

Bbn Technologies Corporation

Other

US Army Corps of Enginees

Richard James Mullen

James Edwin Barger

Ronald A Fowler

Stephen Douglas Milligan

Marshall Seth Brinn

Ronald Bruce Coleman

William Bowles Coney

Peter Allen Krumhansl

Michael Bruce Goldsmith

Matthew Patrick Daily

Robert McGurrin

Daniel Ramsay Cruthirds

Jeffrey Anthony Mazurek

Jason R McKenna

Francis J Fothergill

Stephen D Milligan

Seth Marshall Brinn

Jeffrey Mazurek

Richard Ciosek

Infrared sensing systems having improved vibration cancelation, and methods of achieving improved vibration cancelation. In one example, an infrared sensing system includes an infrared sensor configured to produce a sensor output signal representative of a response of the infrared sensor to infrared excitation and vibration excitation, an accelerometer configured to provide an acceleration signal responsive to the vibration excitation, and a controller, including an adaptive digital filter, coupled to the infrared sensor and to the accelerometer, and configured to receive the acceleration signal and to adjust coefficients of the adaptive digital filter so as to minimize coherence between a residual signal and the acceleration signal, the residual signal being a difference between the sensor output signal and a filter output signal from the adaptive digital filter.

Methods and apparatus for improved sensor vibration cancellation

A system to detect subsurface activity. The system employs vibration sensor pairs, with each sensor pair having a shallow sensor and a deep sensor. Outputs of the sensors of a pair are processed together and events are detected based on the relative values detected by the sensors of the pair. When signal energy departs from a detected background level, the relative amplitude and frequency content of vibrations measured at the shallow and deep sensors may be compared. The comparison may be performed, at least in part, using a classifier that discriminates between subsurface activity and surface activity. The outputs of sensor pairs may be aggregated to make a determination of whether subsurface activity exists and/or its location. Aggregation may involve comparing the outputs of the same sensor pair at multiple time intervals or may involve comparing the outputs of arrayed sensor pairs.

Subsurface intrusion detection system

The systems and methods described herein relate to an airborne shooter detection system having a plurality of sensors coupled to the body of an aircraft such as a helicopter. The sensors are arranged to receive shockwave-only signals. The received signals are analyzed to determine an unambiguous shooter location. The analysis may include measuring the arrival times of the shockwaves of projectiles at each of the sensors, determining the differences in the arrival times among sensors, computing a set of ambiguous solutions corresponding to a shooter, and clustering this set of solutions to determine the unambiguous shooter location. The systems and methods described herein may also be used to determine if multiple shooters are present, and subsequently determine the shooter locations for each of the multiple shooters.

Systems and methods for disambiguating shooter locations with shockwave-only location

Systems and methods for locating the shooter of supersonic projectiles are described. The system uses at least five, preferably seven, spaced acoustic sensors. Sensor signals are detected for shockwaves and muzzle blast, wherein muzzle blast detection can be either incomplete coming from less than 4 sensor channels, or inconclusive due to lack of signal strength. Shooter range can be determined by an iterative computation and/or a genetic algorithm by minimizing a cost function that includes timing information from both shockwave and muzzle signal channels. Disambiguation is significantly improved over shockwave-only measurements.

System and method for identifying a muzzle blast using a multi-sensor total energy approach

Systems and methods for determining shooter locations with weak muzzle detection

Systems and methods for determining and disambiguating the location of the shooter of supersonic projectiles based on shockwave-only signals are described. Using several spaced sensors, an initial portion of the shockwave-only signals is sensed to determine Time-Differences-Of-Arrival (TDOA) for the sensor pairs. The resulting TDOAs are used to determine the gradient of curvature of the shockwave wavefront on the sensors. The gradient of curvature is then used to determine the disambiguated projectile trajectory.

System and method for disambiguating shooter locations

Systems and methods for locating the shooter of supersonic projectiles based on shockwave-only measurements are described. Muzzle blast signals are neither sought nor required. The system uses at least five, preferably seven, acoustic sensors that are spaced apart at least 1 meter. The sensor signals are acquired with a time resolution in the order of microseconds and processed to find and disambiguate the shockwave arrival angle unit vector. Two different Time-Difference-Of-Arrival (TDOA) measurement techniques are described, with one technique using counters in each signal channel and the other technique using cross-correlation between signal channels. A genetic algorithm can be used to efficiently disambiguate the results.

A trench leveling blade is movably mounted between a pair of side walls which are slotted to receive the bucket of a backhoe or other excavating machine. The blade is vertically adjustable with a hand operated jack screw. Rollers mounted in front and back of the blade support the blade during use and guide the blade during its vertical adjustment. A pair of adjustable scraper blades is provided on opposite sides of the leveling blade to clean the surface of the pavement adjoining the trench or any other surface being worked by the leveling blade.

Trench restoration apparatus

Growing community of inventors

Needham, MA, United States of America

Richard James Mullen