摘要:
A method and system for ultrasonic locationing using time difference of arrival measurements includes an ultrasonic receiver including three microphones each disposed on a periphery of a housing and a fourth centrally-positioned microphone. A controller establishes only time difference of arrival measurements of an ultrasonic signal at each microphone, assumes an arbitrary flight time for the signal in order to obtain three flight distances of the signal at each of the three microphones, calculates an intersection point of three spheres having radii equal to the three flight distances, calculates a distance from the intersection point to the central microphone, subtracts the distance from a sum of the arbitrary flight time plus the time difference of arrival measurement for the central microphone to establish an test error, and searches different arbitrary flight times along a straight line through the central microphone and intersection point until the test error is less than a threshold, indicating an actual location of the emitter.
摘要:
A method for detecting series of substantially periodic bursts of substantially sinusoidal signals, in particular, but not exclusively, series of bursts of signals transmitted recurrently (by pingers for example), this method making it possible to ensure the quick and reliable detection of such signals in the presence of significant interference noise. This method includes slightly delayed processing of received signals, spectral analysis and time integration, and presentation of the results in the form of a two-dimensional image of the successive recurrences of the bursts according to time slots of the received signals.
摘要:
A receiving device captures sounds signals (e.g., ultrasonic) from multiple sound signal sources, selects the sound signals satisfying a reliability condition for use in determining an initial position of the receiving device relative to the corresponding sound signal sources, determines the initial position of the receiving device using multilateration of the selected sound signals, and updates the current position of the receiving device as the reliability of individual sound signals varies in the presence of dynamically changing environmental interference, multipathing, and movement between the receiving device and the sound signal sources.
摘要:
Methods and transducers for producing acoustical signals having a spiral wavefront with omnidirectional magnitude and a phase that varies with angle and transducers for producing broadband omnidirectional reference signals for underwater navigation and communication.
摘要:
A position determining method and a work result management device. A position where work is done inside a space surrounded by surfaces is determined, wherein the position where work is done inside the space is a sidewall, wave receivers that receive an acoustic wave signal are placed at three or more points, which are on the same plane substantially parallel to the sidewall but not collinear with one another and whose position coordinates are known. The signal is transmitted from a wave transmitter that transmits an acoustic wave and is placed at the position on the sidewall where work is done, and the respective arrival times of the signal at the three or more wave receivers that are not collinear with one another are measured to determine the position coordinates of the wave transmitter using the arrival times and the position coordinates of the three or more wave receivers.
摘要:
A method of locating an acoustic source using a plurality of vehicles is provided. The method includes transferring acoustic input from a plurality of sensors to a plurality of processing modules, determining a location of each of the vehicles using at least one of a global positioning system module and an inertial motion unit module located in each vehicle, processing, at each processing module, the received acoustic input, designating one of the processing modules a master processing module, and sending processed acoustic input received at each processing module to the master processing module, combining the processed acoustic input at the master processing module, and estimating acoustic source location based on combined processed acoustic data. The method may further include determining if the master processing module is functional, and responsive to determining that the master processing module is not functional, designating a different one of the plurality of processing modules as the master processing module.
摘要:
Disclosed herein is a signal processing apparatus and method for removing a reflected wave generated by a robot platform. The signal processing apparatus includes a transfer function measuring unit for measuring an inter-channel transfer function (IcTF) from signals of a plurality of channels; an impulse response obtaining unit for obtaining an inter-channel impulse response (IcIR) from the IcTF measured by the transfer function measuring unit; and reflected wave removing unit for removing the reflected wave by differentiating a direct wave directly generated by a sound source and the reflected wave with a time delay from the IcIR obtained by the impulse response obtaining unit. The signal processing method of removing a reflected wave includes measuring an IcTF from signals of a plurality of channels; obtaining an IcIR from the measured IcTF; and removing the reflected wave by differentiating a direct wave directly generated by a sound source and a the reflected wave with a time delay from the obtained IcIR.
摘要:
A system and method are described for locating and communicating with miners in an underground mine, in which miners carry a battery-powered signal unit with an impact actuator engagable with a wall, floor, or ceiling surface of the mine to transmit acoustic signals through the ground, and actuate controls on the unit to send a predefined message or a specific message via the impact actuator to ground-coupled acoustic receivers coupled with a base station that includes a decoder to determine the message sent by the miner and a location component to determine the miner's location based on the received signals.
摘要:
An apparatus is described that can monitor the sounds and voices of infants and children in a house by judicially placing nodes in key locations of the home. The network has intelligence and uses voice recognition to enable, disable, reroute, or alter the network. The network uses voice recognition to follow a child from node to node, monitors the children according to activity and uses memory to delay the voices so the adult can hear the individual conversations. An adult that has been assigned privilege can disable all nodes from any node in the network. Another apparatus can locate an individual by voice recognition or sounds they emit including walking, breathing and even a heartbeat. The sound is detected at several microphones that have a specific positional relationship to a room or an enclosement. Triangulations of the time differences of the audio signal detected by the microphones are used to determine the location or position of the audio source in the room. This information can be used to provide an improved audio delivery system to the individual.
摘要:
Systems and methods for estimating projectile trajectory and projectile source location are provided. A method for estimating location information associated with a supersonic projectile propelled from a source includes recording sound at a first location using a single microphone during travel of the supersonic projectile to produce an acoustic recording. The method further includes estimating a miss distance between the first location and a trajectory of the projectile based on the shockwave length. Locating a projectile source includes concurrently recording sound at multiple locations and generating data sets associated with the locations, each of the plurality of data sets including a miss distance, a range, a time of arrival of a muzzle blast from the source, and a time of arrival of a shockwave produced by the projectile. Additionally, the method includes calculating an approximate location of the source at each of the locations based on the data sets.