Abstract: A method and apparatus to improve the performance of acoustic beamformers composed of accelerometer-based Acoustic Vector Sensors (AVS) is disclosed. Most AVS are composed of a set of spatially separated microphones, for which tradeoffs exist based on the array size and number of elements, geometry, frequency bandwidth, and system cost. Accelerometer-based AVS are composed of a one or more triaxial accelerometers, each paired with a collocated MEMS microphone. This results in much smaller array apertures for equivalent performance, and a significant reduction in unwanted sidelobes.

Abstract: An airborne acoustic vector sensor for simultaneously measuring triaxial particle acceleration in three dimensions and pressure includes a triaxial MEMS accelerometer sensitive to an Earth gravitational field. The airborne acoustic vector sensor includes one or multiple MEMS microphones sensitive to sound pressure and overlapping the accelerometer in frequency. The airborne acoustic vector sensor includes a solid body having a density approximating a density of air. The accelerometer is mounted in or upon the solid body. The airborne acoustic vector sensor includes a suspension system supporting the accelerometer and solid body within a framework.

Abstract: An airborne acoustic vector sensor for simultaneously measuring triaxial particle acceleration in three dimensions and pressure includes a triaxial MEMS accelerometer sensitive to an Earth gravitational field. The airborne acoustic vector sensor includes one or multiple MEMS microphones sensitive to sound pressure and overlapping the accelerometer in frequency. The airborne acoustic vector sensor includes a solid body having a density approximating a density of air. The accelerometer is mounted in or upon the solid body. The airborne acoustic vector sensor includes a suspension system supporting the accelerometer and solid body within a framework.

Abstract: In accordance with aspects of the current invention, a method of determining a location of a utility line includes driving one or more transmitters with a continuous wave signal; either adjusting for effects of direct coupling between the transmitters and one or more sensors mounted on the same rigid platform or different platforms or maintaining sufficient separation between a transmitter platform and a sensor platform to minimize such effects; and deriving a position of the line relative to the sensors from the measurements.

Abstract: A locating system is presented. In some embodiments, the locating system includes a first platform, the first platform including a transmitter capable of inducing a current in a line; a second platform, the second platform including a receiver capable of detecting the current in the line; and a processor coupled to the first platform and the second platform, the processor directing the first platform and the second platform to control their motion over the line and collecting location data of the line.

Abstract: A system and method for estimating the magnitude and phase of magnetic and electrical currents in a power line comprising at least one processor operating to create a model of the power line and derive expected complex magnetic and electric-field values; at least one memory; at least one sensor positioned proximate to the at least one power line for sensing and providing measurements of the magnetic and electric fields of the at least one power line; the at least one processor operating to compute a set of complex magnetic and electric field values based upon the measurements provided by the at least one sensor and to estimate parameters related to the complex voltage and/or current of the at least one power line based upon the measured field values and the set of expected complex electric current and voltage values derived from a model of at least one power line.

Abstract: A locating system is presented. In some embodiments, the locating system includes a first platform, the first platform including a transmitter capable of inducing a current in a line; a second platform, the second platform including a receiver capable of detecting the current in the line; and a processor coupled to the first platform and the second platform, the processor directing the first platform and the second platform to control their motion over the line and collecting location data of the line.

Abstract: In accordance with aspects of the current invention, a method of determining a location of a utility line includes driving one or more transmitters with a continuous wave signal; either adjusting for effects of direct coupling between the transmitters and one or more sensors mounted on the same rigid platform or different platforms or maintaining sufficient separation between a transmitter platform and a sensor platform to minimize such effects; and deriving a position of the line relative to the sensors from the measurements.

Abstract: A system and method for providing autonomous navigation for an Autonomous Vehicle such as an Unmanned Air Vehicle (UAV) or an Autonomous Underwater Vehicle (AUV) in the vicinity of power lines or other signal carrying lines or underwater cable is presented. Autonomous navigation is achieved by measuring the magnitude and phase of the electromagnetic field at an unknown location within a space under excitation by a set of power cables of the power line with one or more orthogonal electromagnetic sensors formed on the AV; and estimating parameters related to a position and orientation of the AV, and load parameters of each cable based on the residual error between the measured set of complex electromagnetic field values corresponding to a combined model of the set of power cables.

Abstract: A system for determining the position of an underground sonde transmitter is disclosed. In some embodiments, the system measures a set of complex electromagnetic field magnitude and phase strengths at one or more positions while traversing a target sonde path at any angle using one or more electromagnetic coil sensors, models a set of expected complex electromagnetic strengths of a hypothetical sonde at the positions for one or more of the electromagnetic coil sensors, the set of expected electromagnetic field values corresponding to a model for the target sonde, and estimates parameters related to the target sonde based on the residual error between the measured set of complex electromagnetic field values and the modeled set of expected complex electromagnetic field strengths. A final estimated parameter set is determined after the residual error has converged to a minimum tolerance to indicate the sonde transmitter position.

Abstract: A method for determining the location and orientation of a transmitter object by measuring a set of complex electromagnetic field magnitude and phase strengths within a space using one or more receivers is provided. The method includes modeling a set of expected complex electromagnetic strengths to estimated position and orientation of the transmitter object. And estimating parameters related to the transmitter object position based on the residual error between the measured set of complex electromagnetic field values and a set of expected electromagnetic field values. Further embodiments include a method as above including a plurality of receivers with known positions within a limited space including the transmitter object. A sensor network including a plurality of receivers to perform the above method is also provided. The receivers may communicate using a wireless channel.

Abstract: A system and method for providing autonomous navigation for an Autonomous Vehicle such as an Unmanned Air Vehicle (UAV) or an Autonomous Underwater Vehicle (AUV) in the vicinity of power lines or other signal carrying lines or underwater cable is presented. Autonomous navigation is achieved by measuring the magnitude and phase of the electromagnetic field at an unknown location within a space under excitation by a set of power cables of the power line with one or more orthogonal electromagnetic sensors formed on the AV; and estimating parameters related to a position and orientation of the AV, and load parameters of each cable based on the residual error between the measured set of complex electromagnetic field values corresponding to a combined model of the set of power cables.

Abstract: A system and method for providing autonomous navigation for an Unmanned Air Vehicle (UAV) in the vicinity of power lines is presented. Autonomous navigation is achieved by measuring the magnitude and phase of the electromagnetic field at an unknown location within a space under excitation by a set of power cables of the power line with one or more orthogonal electromagnetic sensors formed on the UAV; modeling a set of expected complex electromagnetic strengths of the set of power cables at the currently estimated position and orientation of the UAV based on a model of the set of power cables; and estimating parameters related to a position and orientation of the UAV, and load parameters of each cable based on the residual error between the measured set of complex electromagnetic field values and the set of expected electromagnetic field values corresponding to a combined model of the set of power cables.

Abstract: A system and method for estimating the magnitude and phase of magnetic and electrical currents in a power line comprising at least one processor operating to create a model of the power line and derive expected complex magnetic and electric-field values; at least one memory; at least one sensor positioned proximate to the at least one power line for sensing and providing measurements of the magnetic and electric fields of the at least one power line; the at least one processor operating to compute a set of complex magnetic and electric field values based upon the measurements provided by the at least one sensor and to estimate parameters related to the complex voltage and/or current of the at least one power line based upon the measured field values and the set of expected complex electric current and voltage values derived from a model of at least one power line.

Abstract: A method for determining the location of an underground sonde transmitter is disclosed. In some embodiments, the method includes measuring a set of complex electromagnetic field magnitude and phase strengths at one or more of positions while traversing a target sonde path at any angle using one or more electromagnetic coil sensors, modeling a set of expected complex electromagnetic strengths of a hypothetical sonde at the one or more of positions for one or more of the electromagnetic coil sensors, the set of expected electromagnetic field values corresponding to a model for the target sonde, and estimating parameters related to the target sonde based on the residual error between the measured set of complex electromagnetic field values and the modeled set of expected complex electromagnetic field strengths, wherein a final estimated parameter set is determined after the residual error has converged to a minimum tolerance.

Abstract: A locator including a communication interface adapted to communicate ticket data with a database, a memory adapted to store the ticket data received from the database, a first transmitter adapted to controllably radiate at least one radiation frequency, a receiver adapted to generate data corresponding to the transmitted radiation frequency, and a processor adapted to reconfigure ticket data based on the generated data, wherein the communication interface communicates the reconfigured ticket data to a network.

Abstract: A method for determining the location of an underground sonde transmitter is disclosed. In some embodiments, the method includes measuring a set of complex electromagnetic field magnitude and phase strengths at one or more of positions while traversing a target sonde path at any angle using one or more electromagnetic coil sensors, modeling a set of expected complex electromagnetic strengths of a hypothetical sonde at the one or more of positions for one or more of the electromagnetic coil sensors, the set of expected electromagnetic field values corresponding to a model for the target sonde, and estimating parameters related to the target sonde based on the residual error between the measured set of complex electromagnetic field values and the modeled set of expected complex electromagnetic field strengths, wherein a final estimated parameter set is determined after the residual error has converged to a minimum tolerance.

Abstract: A system and method for providing autonomous navigation for an Unmanned Air Vehicle (UAV) in the vicinity of power lines is presented. Autonomous navigation is achieved by measuring the magnitude and phase of the electromagnetic field at an unknown location within a space under excitation by a set of power cables of the power line with one or more orthogonal electromagnetic sensors formed on the UAV; modeling a set of expected complex electromagnetic strengths of the set of power cables at the currently estimated position and orientation of the UAV based on a model of the set of power cables; and estimating parameters related to a position and orientation of the UAV, and load parameters of each cable based on the residual error between the measured set of complex electromagnetic field values and the set of expected electromagnetic field values corresponding to a combined model of the set of power cables.

Abstract: A method for determining the location and orientation of a transmitter object by measuring a set of complex electromagnetic field magnitude and phase strengths within a space using one or more receivers is provided. The method includes modeling a set of expected complex electromagnetic strengths to estimated position and orientation of the transmitter object. And estimating parameters related to the transmitter object position based on the residual error between the measured set of complex electromagnetic field values and a set of expected electromagnetic field values. Further embodiments include a method as above including a plurality of receivers with known positions within a limited space including the transmitter object. A sensor network including a plurality of receivers to perform the above method is also provided. The receivers may communicate using a wireless channel.

Abstract: Line locator systems that fuse traditional sensors used in a combined pipe and cable locator (electromagnetic coils, magnetometers, and ground penetrating radar antennas) with low cost inertial sensors (accelerometers, gyroscopes) in a model-based approach are presented. Such systems can utilize inexpensive MEMS sensors for inertial navigation. A pseudo-inertial frame is defined that uses the centerline of the tracked utility, or an aboveground fixed object as the navigational reference. An inertial sensor correction mechanism that limits the tracking errors over time when the model is implemented in state-space form using, for example, the Extended Kalman Filter (EKF) is disclosed.