Patent application number | Description | Published |
20140064742 | EVENT SYNCHRONIZATION FOR OPTICAL SIGNALS - A system for synchronizing an optical signal with an initiation of an event can include an event controller which controls the initiation of the event, and an optical modulator which modulates the optical signal in response to receipt of an indication from the event controller that the event is initiated. A method of synchronizing an optical signal with an initiation of an event can include transmitting from an event controller an indication that the event is initiated, receiving the indication that the event is initiated, and modulating the optical signal in response to the receiving. A system for synchronizing multiple optical signals can include at least one time-code generator which generates time-codes, and multiple optical modulators which modulate the respective optical signals in response to generation of the time-codes by the at least one time-code generator. | 03-06-2014 |
20140150523 | CALIBRATION OF A WELL ACOUSTIC SENSING SYSTEM - A method of calibrating a distributed acoustic sensing system can include receiving predetermined acoustic signals along acoustic sensors distributed proximate a well, and calibrating the system based on the received acoustic signals. A method of calibrating an optical distributed acoustic sensing system can include displacing an acoustic source along an optical waveguide positioned proximate a well, transmitting predetermined acoustic signals from the acoustic source, receiving the acoustic signals with the waveguide, and calibrating the system based on the received acoustic signals. A well system can include a distributed acoustic sensing system including an optical waveguide installed in a well, and a backscattered light detection and analysis device, and at least one acoustic source which transmits predetermined acoustic signals at spaced apart locations along the waveguide. The device compensates an output of the system based on the acoustic signals as received at the locations along the waveguide. | 06-05-2014 |
20140203946 | OPTICAL WELL LOGGING - A method of logging a well can include conveying an optical waveguide and at least one signal generator with a conveyance into the well, causing the signal generator to generate at least one signal in the well, and receiving the signal as distributed along the optical waveguide. A well logging system can include a conveyance with an optical waveguide, and at least one signal generator which is conveyed by the conveyance into a well with the optical waveguide, whereby the signal generator generates at least one signal received with the optical waveguide. | 07-24-2014 |
20140204712 | DOWNHOLE OPTICAL ACOUSTIC TRANSDUCERS - A method of generating an acoustic signal in a subterranean well can include converting optical energy to acoustic energy downhole, thereby transmitting the acoustic signal through a downhole environment. A well system can include an optical acoustic transducer disposed in the well and coupled to an optical waveguide in the well, whereby the transducer converts optical energy transmitted via the optical waveguide to acoustic energy. An optical acoustic transducer for use in a subterranean well can include various means for converting optical energy transmitted via an optical waveguide to acoustic energy in the well. | 07-24-2014 |
20150098673 | GEO-LOCATING POSITIONS ALONG OPTICAL WAVEGUIDES - A method of correlating physical locations with respective positions along an optical waveguide can include transmitting to the waveguide a signal including an indication of the transmitting location, and the waveguide receiving the signal. A system for correlating a physical location with a position along an optical waveguide can include a transmitter which transmits to the optical waveguide a signal including an indication of the transmitter location, and a computer which correlates the location to the position, based on the signal as received by the waveguide. A method of determining a position along an optical waveguide at which a signal is transmitted can include modulating on the signal an indication of a transmission location, and transmitting the signal to the waveguide, thereby causing vibration of the waveguide. | 04-09-2015 |
20150114127 | DISTRIBUTED ACOUSTIC SENSING SYSTEMS AND METHODS EMPLOYING UNDER-FILLED MULTI-MODE OPTICAL FIBER - An illustrative distributed acoustic sensing system includes a multi-mode optical fiber cable for distributed sensing and a distributed acoustic sensing interrogator coupled to the multi-mode optical fiber cable via a single mode optical fiber. The interrogator derives distributed acoustic measurements from Rayleigh backscattering light that is initiated with a substantially under-filled launch configuration that is designed to excite only the lowest-order modes of the multi-mode optical fiber. Mode conversion within the multi-mode optical fiber is anticipated to be negligible. For elastic scattering (i.e., Rayleigh scattering), it is further anticipated that the scattered light will be primarily returned in the incident propagation mode, thereby escaping the extraordinarily large coupling loss that would otherwise be expected from coupling a single-mode optical fiber to a multi-mode optical fiber for distributed sensing. Experiments with graded index multi-mode optical fiber have yielded positive results. | 04-30-2015 |
20150116124 | Robust Optical Fiber-Based Distributed Sensing Systems and Methods - An illustrative distributed sensing system includes a fiberoptic cable, a transmitter module, and a receiver module. The transmitter module is coupled to the fiberoptic cable to communicate light in each of multiple independent paths to each of multiple positions along the cable, The receiver module is coupled to the fiberoptic cable to receive backscattered light from said multiple positions along the cable via the multiple independent paths. The receiver module includes at least one receiver for each of said multiple independent paths to obtain simultaneous measurements for each of said multiple positions. The multiple independent paths may be provided by wave division multiplexing, frequency division multiplexing, spatial mode division multiplexing, multicore fiber, and/or multiple fibers. | 04-30-2015 |
Patent application number | Description | Published |
20090043439 | Guidance, Navigation, and Control System for a Vehicle - The present invention provides a guidance, navigation, and control method and system for an underground mining vehicle that allow said vehicle to be taught a route by a human operator and then have it automatically drive the route with no human intervention. The method works in three steps: teaching, route profiling, and playback. In the teaching step the vehicle is manually driven by a operator (or using tele-operation whereby the operator views a screen displaying live views from vehicle-mounted cameras and using remote controls) along a route which can consist of an arbitrary sequence of maneuvers including tramming forwards, switching directions, tramming backwards, turning, or pausing movement. During this phase raw data from vehicle-mounted sensors including odometric sensors and rangefinders are logged to a file throughout teaching for later processing. During the (offline) route profiling step, the raw data in the log file are processed into a route profile including a vehicle path, a sequence of local metric submaps located along the path, and a profile of desired speed as a function of distance along the path. During the playback step, the vehicle automatically repeats the route that was taught during the teaching phase, as represented by the route profile. This is accomplished by first determining where the vehicle is on the route using a localization method which uses the odometric and laser rangefinder sensors and the local metric maps to determine the vehicle location. A steering control method adjusts the vehicle's steering to ensure it tracks the intended path. A drive control method adjusts the vehicle's speed accordingly and safety method ensures the vehicle stops in the event that an obstruction is on the vehicle's intended path. | 02-12-2009 |
20120035798 | GUIDANCE, NAVIGATION, AND CONTROL SYSTEM FOR A VEHICLE - The present invention provides a guidance, navigation, and control method and system for an underground mining vehicle that allow said vehicle to be taught a route by a human operator and then have it automatically drive the route with no human intervention. The method works in three steps: teaching, route profiling, and playback. In the teaching step the vehicle is manually driven by a operator (or using tele-operation whereby the operator views a screen displaying live views from vehicle-mounted cameras and using remote controls) along a route which can consist of an arbitrary sequence of maneuvers including tramming forwards, switching directions, tramming backwards, turning, or pausing movement. During this phase raw data from vehicle-mounted sensors including odometric sensors and rangefinders are logged to a file throughout teaching for later processing. During the (offline) route profiling step, the raw data in the log file are processed into a route profile including a vehicle path, a sequence of local metric submaps located along the path, and a profile of desired speed as a function of distance along the path. During the playback step, the vehicle automatically repeats the route that was taught during the teaching phase, as represented by the route profile. This is accomplished by first determining where the vehicle is on the route using a localization method which uses the odometric and laser rangefinder sensors and the local metric maps to determine the vehicle location. A steering control method adjusts the vehicle's steering to ensure it tracks the intended path. A drive control method adjusts the vehicle's speed accordingly and safety method ensures the vehicle stops in the event that an obstruction is on the vehicle's intended path. | 02-09-2012 |