Direction (e.g., Compass) Patents (Class 702/92)
  • Publication number: 20100312509
    Abstract: Measurement data is collected from a magnetic sensor in a portable device, while the device is being carried by its end user and without requiring the end user to deliberately rotate or position the device while the output data is being collected. For example, the device may be held in the user's hand while walking or standing, or it may be fixed to the dashboard of an automobile or boat. Measurement data may also be collected from one or more positing, orientation or movement sensors. The collected measurement data from one or both of the magnetic sensor and the position, orientation or movement sensor is processed. In response, either a 2D compass calibration process or a 3D process is signaled to be performed. Other embodiments are also described and claimed.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 9, 2010
    Applicant: Apple Inc.
    Inventors: Parin Patel, Ronald K. Huang, Patrick S. Piemonte, Robert Mayor
  • Publication number: 20100312513
    Abstract: Responsive to a recalibration trigger event, magnetometer data output by a magnetometer can be compared to historical magnetometer data previously output by the magnetometer. If a match is determined, a confidence of the match can be determined using theoretically constant data related to Earth's magnetic field. The constant data can be calculated from the historical magnetometer data. If the confidence of the match exceeds a confidence threshold level, historical calibration data can be used to calibrate the magnetometer. If the confidence of the match does not exceed the confidence threshold level, a calibration procedure can be performed to generate new calibration data, and the new calibration data can be used to calibrate the magnetometer.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 9, 2010
    Inventors: Robert Mayor, Ronald Keryuan Huang, Patrick Piemonte
  • Publication number: 20100307015
    Abstract: Multiple instances of a geomagnetic field are calculated. Multiple instances of an average magnitude of a subset of the instances of the geomagnetic field are also calculated. When the average magnitude changes by more than a first predetermined threshold, the user is informed that compass accuracy has degraded. Other embodiments are also described and claimed.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 9, 2010
    Applicant: Apple Inc.
    Inventors: Robert Mayor, Patrick S. Piemonte, Ronald K. Huang, Parin Patel
  • Publication number: 20100299093
    Abstract: A bearing calculator provided with a geomagnetic sensor for detecting earth-geomagnetism and a control unit for calculating a geographical bearing based on detection values of the geomagnetic sensor. The control unit can execute offset error correction processing for correcting the offset error to the geomagnetic sensor based on a change in the magnetic field inside the bearing calculator. When detection values of the geomagnetic sensor enter an abnormal state, it performs said offset error correction processing when the abnormal state continues for a predetermined time, while does not perform the offset error correction processing when the abnormal state ends within a predetermined time.
    Type: Application
    Filed: August 2, 2010
    Publication date: November 25, 2010
    Applicant: KYOCERA CORPORATION
    Inventor: Shigeo OKEYA
  • Patent number: 7835878
    Abstract: In a travel angle detection system for a mobile object having a detector installed in the mobile object to produce angular velocity outputs successively, the detector outputs are read and one output is determined as a provisional calibration value indicative of zero-point. Integrated values of differences between the calibration value and successive outputs and output variation width are calculated. When they are within predetermined permissible ranges, the mobile object is determined to be in static condition and the calibration value is corrected by an average value of the integrated values. The travel angle of the mobile object is detected from the calibrated outputs of the detector, thereby achieving accurate calibration of detector output by enabling accurate determination of the static condition.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: November 16, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventor: Mitsuyasu Ino
  • Patent number: 7835879
    Abstract: Measurements are acquired from a magnetic sensor during a non-pre-ordered movement, and a plurality of sets of solutions are determined for respective expected values of intensity of the Earth's magnetic field. The solutions are defined by a plurality of parameters, including at least one gain value for each detection axis of the magnetic sensor. For each solution, a figure of merit is determined, correlated to a calibration error, and a partial solution is selected in each set of solutions, based on the figure of merit. Once a gain confidence interval has been defined, a calibration solution is selected based on the figure of merit, from among the partial solutions having respective gain values all falling within the gain confidence interval.
    Type: Grant
    Filed: August 22, 2008
    Date of Patent: November 16, 2010
    Assignee: STMicroelectronics S.r.l.
    Inventors: Francesco Vocali, Fabio Biganzoli
  • Publication number: 20100286940
    Abstract: An information processing program is provided, which is executed by a computer of an information processing apparatus that executes predetermined processing based on acceleration data outputted from an input device including an acceleration sensor for detecting acceleration. The information processing program causes the computer to function as data obtaining means, change amount calculation means, and gravity direction calculation means. The data obtaining means repeatedly obtains the acceleration data. The change amount calculation means calculates, by using a history of acceleration indicated by the acceleration data, a change amount of acceleration generated in the input device. The gravity direction calculation means calculates a direction of gravity of the input device by using the acceleration indicated by the acceleration data, based on the change amount of the acceleration.
    Type: Application
    Filed: July 28, 2009
    Publication date: November 11, 2010
    Inventor: Takuhiro DOHTA
  • Patent number: 7826999
    Abstract: The instant invention utilizes two, optionally orthogonal and optionally slightly tilted, horizontal magnetic sensors and, optionally, a 2 or 3 axis accelerometer or inclinometer to calculate a pitch, roll and tilt compensated heading. A vertical, Z, component is relatively constant compared to X and Y components, the Z component can be abstracted from the X and Y sensor when pitch and roll is applied based on Z offset measured with X or Y sensor at high tilt angles. Additional sensors tilted at various ? degrees can be added with a different angle ? to X sensors when additional horizontal and magnetic coverage is desirable.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: November 2, 2010
    Assignee: PNI Corporation
    Inventors: Anders Boeen, Andrew T. Taylor, Davy J. Figaro
  • Patent number: 7818136
    Abstract: One or more sensors in a portable electronic device have individual status parameter in response to different using configurations. When the portable electronic device operates in a first using configuration, an electronic compass in the portable electronic device loads a corresponding first default setting, according to the status parameter of the sensors operated in the first using configuration, and detects the geomagnetic field for outputting azimuth data. When the portable electronic device changes its configuration from the first using configuration to a second using configuration, the electronic compass stops detecting the geomagnetic field and loads a corresponding second default setting, according to the status parameter of the sensors operated in the second using configuration, and detects the geomagnetic field for outputting azimuth data.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: October 19, 2010
    Assignee: HTC Corporation
    Inventors: Tsan-Yuan Chen, Yu-Peng Lai
  • Publication number: 20100250176
    Abstract: A compass system comprises a magnetic field sensor for measuring an ambient magnetic field and a magnetic field generator, corresponding to the magnetic field sensor, configured to generate a reference magnetic field. The magnetic field sensor is configured to measure the reference magnetic field. The compass system further comprises a control circuit operably connected to the magnetic field sensor and magnetic field generator, wherein the control circuit is configured to process the ambient magnetic field and the reference magnetic field measurements to determine an absolute reference field strength for use in calibrating the compass system.
    Type: Application
    Filed: March 31, 2009
    Publication date: September 30, 2010
    Inventor: Jason L. Reene
  • Publication number: 20100236084
    Abstract: A system for testing the accuracy of an electronic compass is disclosed. The system includes a circular track, a compass seat, an electromagnetic element, a driver, a power source, a calculator, and a magnetic shielding chamber. The electromagnetic element is disposed on the circular track and powered by the power source to generate a magnetic field. The electronic compass is installed on the compass seat and surrounded by the circular track. As such, the electronic compass can measure the magnetic field of the electromagnetic element and calculate direction relative to the electromagnetic element at different points of the circular track when the electromagnetic element is driven by the driver to move along the circular track. The magnetic shielding chamber is for shielding the electromagnetic element and the electronic compass from interference of external magnetic fields.
    Type: Application
    Filed: August 4, 2009
    Publication date: September 23, 2010
    Applicant: HON HAI PRECISION INDUSTRY CO., LTD.
    Inventor: TSUNG-JEN CHUANG
  • Patent number: 7743519
    Abstract: A sensor module maintaining high detection accuracy. Correction data of a detected magnetic field is updated only in a case that a fluctuation band acquired from an output signal of an acceleration sensor is less than a threshold value and a difference between an azimuth angle acquired from an output signal of a terrestrial magnetism sensor and an inclination angle acquired from an output signal of acceleration sensor is less than the threshold value. Therefore, the correction data is updated only in a case that a magnetic field at a position of a mobile object is stably detected, and an accuracy of the correction data can be maintained.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: June 29, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Futoyoshi Kou, Akihiro Fuse
  • Publication number: 20100156653
    Abstract: An assessment device is provided which allows for measurement of a position of interest, e.g., a body part, while a subject is in a functional position, such as may be required for the demands of an activity of interest without also requiring a lengthy setup time, tethered connection to other equipment external to the subject or tedious manual measurements. Moreover, an indicator such as an alarm or other output may be provided for receiving immediate, real time feedback, such as when a functional activity falls outside a tolerance or threshold.
    Type: Application
    Filed: May 14, 2008
    Publication date: June 24, 2010
    Inventors: Ajit Chaudhari, Chistopher McKenzie
  • Publication number: 20100153050
    Abstract: Techniques and systems are disclosed for performing a gravity survey near the seafloor. In one aspect, a system includes an autonomous underwater vehicle that includes a sensor system holding area. The system includes a gravity sensor system to fit inside the sensor system holding area of the autonomous underwater vehicle. The gravity sensor system includes a motorized gimbal to provide a leveled sensor platform. Also, the gravity sensor system includes a gravimeter sensor mounted onto the motorized gimbal to measure gravity data. Further, the payload includes a motion sensor mounted onto the motorized gimbal to measure motion data associated with movements of the autonomous underwater vehicle.
    Type: Application
    Filed: November 12, 2009
    Publication date: June 17, 2010
    Inventors: Mark A. Zumberge, Glenn Sasagawa, Richard Zimmerman, Jeff Ridgway
  • Publication number: 20100114517
    Abstract: An orientation sensing system uses an algorithm that iteratively improves an estimate of the body attitude. In each iteration, an error vector is generated that represents the difference between the actually measured sensor signals on the one hand, and a model-based prediction of these sensor signals, given the attitude estimate of the previous iteration, on the other hand. From the compound sensor data error vector, an attitude estimation error (a 3 degrees-of-freedom rotation) is calculated by multiplying the compound error vector by the pseudo-inverse of a sensitivity matrix. An improved attitude estimate is then obtained by applying the inverse of the attitude estimation error to the old attitude estimate.
    Type: Application
    Filed: March 27, 2008
    Publication date: May 6, 2010
    Applicant: NXP, B.V.
    Inventors: Hans Marc Bert Boeve, Teunis Jan Ikkink
  • Patent number: 7684945
    Abstract: In a method for the calibration of a yaw rate measurement in a motor vehicle, the motor vehicle features at least one device for determining the yaw rate, a camera system which is oriented in the forward direction, and, if applicable, a steering angle sensor or a lateral acceleration sensor. At least one initial calibration is carried out at a standstill and at least one second calibration is carried out when the motor vehicle is moving. The second calibration uses image data of the camera system, which detects the environment in front of the motor vehicle, to predict the course of the roadway lane on which the vehicle is driving, from which the yaw rate is estimated.
    Type: Grant
    Filed: April 19, 2007
    Date of Patent: March 23, 2010
    Assignee: ADC Automotive Distance Control Systems GmbH
    Inventors: Michael Walter, Matthias Zobel, Johannes Hoer
  • Patent number: 7680336
    Abstract: An imaging apparatus index detecting unit detects an index in a physical space from an image captured by an imaging apparatus including a first camera. A position and orientation estimating unit estimates the position and orientation of the imaging apparatus based on information relating to image coordinates of a detected index. A second camera index candidate detecting unit monitors an index on the imaging apparatus with a second camera positioned in the physical space, and detects an index candidate. A position constraint condition calculating unit calculates a position constraint condition based on information relating to image coordinates of a detected index candidate. A second camera index identifying unit identifies a second camera index based on the estimated position and orientation of the imaging apparatus and the position constraint condition of the second camera index candidate.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: March 16, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takaaki Endo, Kiyohide Satoh
  • Publication number: 20100063763
    Abstract: A self-calibrating gyroscope system provides improved estimates of, and compensation or calibration for, scale factor errors and bias errors. The gyroscope system employs a plurality of gyroscope units having sense or input axes in a mutually non-parallel arrangement. The number of gyroscope units is preferably at least one more than the number of axes for which rate estimates is required. A Mode Reversal technique is used to obtain an estimate of bias error for a selected gyroscope. A Random Closed-Loop Scale Factor technique is used to obtain an estimate of scale factor error for a selected gyroscope. Because the Mode Reversal technique temporarily disrupts operation of the affected gyroscope, each of the gyroscopes may be taken offline temporarily, in turn, for calibration, and thereafter returned to normal operation.
    Type: Application
    Filed: September 11, 2008
    Publication date: March 11, 2010
    Inventor: David M. Rozelle
  • Publication number: 20100017160
    Abstract: Devices (1) comprising sensor arrangements (2) for providing first field information (11-13) defining at least parts of first fields and for providing second field information (14, 15) defining at least parts of second fields are provided with updaters (4) for updating parameters of the first and/or second fields via criterion-dependent iterations, to become more reliable and user friendly. The fields may be earth gravitational fields and/or earth magnetic fields and/or further fields. The parameters comprise magnitudes of the fields and dot products of the fields. The criterion-dependent iterations comprise magnitude functions and dot product functions. The magnitude functions define new magnitudes being functions of old magnitudes and of updated magnitudes and the dot product functions define new dot products being functions of old dot products and of updated dot products.
    Type: Application
    Filed: April 27, 2006
    Publication date: January 21, 2010
    Applicant: NXP B.V.
    Inventors: Teunis Jan Ikkink, Hans Marc Bert Boeve, Gerjan Van De Walle
  • Publication number: 20100010765
    Abstract: An improved procedure for calibrating the azimuth angle in a metrology module for use in a metrology system that is used for measuring a target on a wafer, and the metrology modules can include oblique Spectroscopic Ellipsometry (SE) and unpolarized or polarized spectroscopic reflectometer devices.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 14, 2010
    Applicant: Tokyo Electron Limited
    Inventor: Shifang Li
  • Publication number: 20090320305
    Abstract: A portable electronic apparatus able to execute processing concerning calibration of a geomagnetism sensor at a suitable timing and a method of calibration of such a geomagnetism sensor are provided. Further, when a key of a key input part (103) is operated in a power-saving mode, the power-saving mode ends, and the processing concerning the calibration of a detection value of a geomagnetism sensor (110) is executed. Due to this, the processing concerning the calibration is executed in a state where a user tries to view a screen of a display part (107), therefore the calibration processing is executed in a state where an angle of housings with respect to the horizontal plane is suitable, and a calculation precision of a bearing can be improved.
    Type: Application
    Filed: March 29, 2007
    Publication date: December 31, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Kazuto Ito, Yasuhiro Ueno
  • Patent number: 7640106
    Abstract: Apparatus for determining the position of a selected object relative to a moving reference frame, the apparatus including at least one reference frame transceiver assembly firmly attached to the moving reference frame, at least one object transceiver assembly firmly attached to the selected object, an inertial measurement unit firmly attached to the selected object, an inertial navigation system firmly attached to the moving reference frame, and a tracking processor coupled with the object transceiver assembly, with the inertial measurement unit and with the inertial navigation system, the object transceiver assembly communicating with the reference frame transceiver assembly using magnetic fields, the inertial measurement unit producing IMU inertial measurements of motion of the selected object with respect to an inertially fixed reference frame, the inertial navigation system producing INS inertial measurements of motion of the moving reference frame with respect to the inertially fixed reference frame, the
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: December 29, 2009
    Assignee: Elbit Systems Ltd.
    Inventors: Saul Stokar, David Neustadter
  • Publication number: 20090300928
    Abstract: A mobile electronic apparatus capable of effectively preventing erroneous recognition of a bearing (azimuth or compass direction) by a user, as a correct display of the bearing is correct when the reliability of the display of the bearing is lowered by a change of the usage environment, and a bearing display method of the same, are provided. If a mobile electronic apparatus (100) is mounted on a charger (200) having a speaker (201), while information on a bearing calculated according to geomagnetism detected by a geomagnetic sensor (108) is displayed on a display part (107), updating of the information on the bearing repeated up to them is stopped, and information on a predetermined bearing is continuously displayed on the display part (107). This enables a user to correctly recognize that the information on the bearing displayed on the display part (107) is incorrect, thereby preventing the user from being misled by the unreliable information on the display part (107).
    Type: Application
    Filed: January 30, 2007
    Publication date: December 10, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Yasuhiro Ueno, Kazuto Ito
  • Publication number: 20090292495
    Abstract: In one embodiment a method and corresponding apparatus are arranged to determine an accurate device heading by continuously combining an average magnetic heading with the compensated inertial heading. The example embodiment obtains the compensated inertial heading by compensating for a time delay of an inertial heading.
    Type: Application
    Filed: May 20, 2008
    Publication date: November 26, 2009
    Inventors: Alfonso R. Navarro, JR., Frederic S. Boericke, II, Kenneth D. Rolt, Stephen G. Boucher, Roger H. Tancrell
  • Publication number: 20090292496
    Abstract: A compass compensation system is provided for automatically and continuously calibrating an electronic compass for a vehicle, without requiring an initial manual calibration or preset of the vehicle magnetic signature. The system initially adjusts a two axis sensor of the compass in response to a sampling of at least one initial data point. The system further calibrates the compass by sampling data points that are substantially opposite to one another on a plot of a magnetic field and averaging an ordinate of the data points to determine a respective zero value for the Earth magnetic field. The system also identifies a change in magnetic signature and adjusts the sensor assembly.
    Type: Application
    Filed: August 3, 2009
    Publication date: November 26, 2009
    Applicant: DONNELLY CORPORATION
    Inventors: Kenneth L. Schierbeek, Eric J. Hoekstra, Rodney K. Blank, Merdad Veiseh, Gregory H. DeVette, Kenneth Schofield
  • Patent number: 7613581
    Abstract: A method of calibrating a compass sensor in consideration of a magnetic environment is provided. The method includes (a) acquiring magnetic force data by rotating a compass sensor 360 degrees, the compass sensor including a biaxial magnetometer, (b) fitting the acquired magnetic force data to an ellipse function, (c) transforming the acquired magnetic force data and the ellipse function into a circle which is centered on an origin, and (d) calculating a distortion factor based on an inclination of a major axis of the ellipse function or the acquired magnetic force data to a horizontal axis, the distortion factor indicating the degree to which a magnetic field is distorted.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: November 3, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Vladimir Skvortsov, Seok-won Bang, Hyoung-ki Lee
  • Patent number: 7613567
    Abstract: First and second acceleration sensor elements for detecting the acceleration of a vehicle in the direction in which the vehicle travels, and the acceleration of the vehicle in the direction transverse to the travel direction of the vehicle are mounted on a sensor substrate which is mounted on a control substrate of a vehicle control device. With the sensor substrate positioned such that the sensing directions of the respective sensor elements are perpendicular to or parallel to the vertical line, the outputs of the respective sensor elements are detected as zero errors or gain errors. The sensor substrate is then mounted on a vehicle and with the vehicle placed on a horizontal surface, a signal is sent to an electronic control unit (ECU) of the vehicle control device so that the ECU can recognize that the vehicle is horizontal. Based on the outputs from the first and second sensor elements at this time, the deviation angles of the sensor elements about the X-axis and Y-axis directions are calculated.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: November 3, 2009
    Assignee: Advics Co., Ltd.
    Inventor: Hitoshi Hashiba
  • Patent number: 7606676
    Abstract: In a compass sensor unit, an azimuth data computing method is carried out by the steps of: inputting a signal from a geomagnetic sensor to measure magnetic field; determining whether to store measurement data of the magnetic field based on a distance from the last stored measurement data; calculating an offset value based on the stored data; making a comparison for each component of a plurality of measurement data used for calculating the offset value, and judging the offset value to be valid when a difference between the maximum and minimum values of each component is a given value or more; updating the already stored offset value to the offset value judged to be valid; and correcting newly provided measurement data by the updated offset value to compute azimuth data.
    Type: Grant
    Filed: September 8, 2008
    Date of Patent: October 20, 2009
    Assignee: Yamaha Corporation
    Inventors: Hideki Sato, Yukio Wakui, Masayoshi Omura
  • Publication number: 20090254294
    Abstract: An electronic circuit includes an electronic compass (e-compass 1150) having e-compass sensors (X, Y, Z) mounted on different axes and operable to supply e-compass sensor data, memory circuitry (1024), and an electronic processor (1030) coupled to said e-compass sensors (1150, X, Y, Z) and to said memory circuitry (1024), said electronic processor (1030) operable to execute an electronic ellipse-fitting procedure responsive to the e-compass sensor data to generate at least one signal related to an ellipse tilt angle (?), and store the at least one signal in said memory circuitry (1024) as a tilt calibration parameter for the e-compass. Processes for calibrating an e-compass, as well as electronic circuits and processes for correcting measured heading, and processes of manufacture are also disclosed.
    Type: Application
    Filed: March 5, 2009
    Publication date: October 8, 2009
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Goutam Dutta
  • Patent number: 7581326
    Abstract: A heading sensor includes a housing containing an interferometer having a mirror movable in response to fluctuations in a gravitational force applied to the housing. The interferometer, responsive to a light beam, generates an optical signal modulated according to the relative displacement of the mirror. The housing further includes an electromagnetic coil positioned along an axis of the housing for generating a current signal indicative of fluctuations in a magnetic field applied to the housing. The heading sensor also includes a processor for determining a local gravitational field component according to the optical signal and a local magnetic field component according to the current signal.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: September 1, 2009
    Assignee: Lockheed Martin Corporation
    Inventors: Jeffrey A. Bulow, Marcus B. Niessen
  • Patent number: 7558688
    Abstract: A method for calibrating a sensor mounted on an aircraft includes the steps of: using an optical device to create reference points which define a reference line that is parallel to both horizontal and vertical planes of the sensor, and using the reference line to calibrate the sensor with respect to a reference coordinate system.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: July 7, 2009
    Assignee: Northrop Grumman Corporation
    Inventors: Roy Schering, Wayne John Gordon, Donald Richard McMillan, David Curtis Lennon, Marc S. Adams
  • Publication number: 20090171608
    Abstract: In a magnetic data processing device, a magnetic data input part sequentially receives magnetic data output from a three-dimensional (3D) magnetic sensor. A storage part stores a plurality of the magnetic data as a data set of statistical population. An acceleration data input part receives acceleration data output from a 3D acceleration sensor. A reliability determination part derives a reliability index that is a function of an angular difference between a direction of a line perpendicular to an approximate plane representing a distribution of the data set of the statistical population and a direction of acceleration represented by the acceleration data.
    Type: Application
    Filed: December 23, 2008
    Publication date: July 2, 2009
    Applicant: Yamaha Corporation
    Inventor: Ibuki Handa
  • Publication number: 20090171607
    Abstract: One or more sensors in a portable electronic device have individual status parameter in response to different using configurations. When the portable electronic device operates in a first using configuration, an electronic compass in the portable electronic device loads a corresponding first default setting, according to the status parameter of the sensors operated in the first using configuration, and detects the geomagnetic field for outputting azimuth data. When the portable electronic device changes its configuration from the first using configuration to a second using configuration, the electronic compass stops detecting the geomagnetic field and loads a corresponding second default setting, according to the status parameter of the sensors operated in the second using configuration, and detects the geomagnetic field for outputting azimuth data.
    Type: Application
    Filed: December 17, 2008
    Publication date: July 2, 2009
    Inventors: Tsan-Yuan Chen, Yu-Peng Lai
  • Patent number: 7532991
    Abstract: In a magnetic data processing device, an input part sequentially inputs magnetic data outputted from a two-dimensional or three-dimensional magnetic sensor. The magnetic data is two-dimensional or three-dimensional vector data that is a linear combination of a set of fundamental vectors. The magnetic data processing device stores a plurality of the inputted magnetic data as a data set of statistical population in order to update an old offset of the magnetic data with a new offset. An offset derivation part derives the new offset based on the old offset and the data set of statistical population under a constraint condition that the new offset be obtained as the sum of the old offset and a correction vector.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: May 12, 2009
    Assignee: Yamaha Corporation
    Inventor: Ibuki Handa
  • Publication number: 20090089001
    Abstract: A method and system for Self-calibrated Azimuth and Attitude Accuracy Enhancing are disclosed, wherein SAAAEMS approach is based on fully auto-calibration self-contained INS principles, not depending on magnetometers for azimuth/heading determination, and thus the system outputs and performance are not affected by the environmental magnetic fields. In order to reduce the system size and cost, this new innovative methods and algorithms are used for SAAAEMS system configuration and integration. Compared to a conventional INS for gyrocompassing, AGNC's approach uses a smaller number of high accuracy sensors: SAAAEMS uses only one 2-axis high accuracy gyro (for example, one DTG) instead of 3-axis; the third axis gyro is a MEMS gyro. It uses only 2 high accuracy accelerometers instead of 3, since the two accelerometers are used only for gyrocompassing not for navigation. These two changes to the conventional INS system configuration remarkably reduce the whole system size and cost.
    Type: Application
    Filed: August 14, 2008
    Publication date: April 2, 2009
    Inventor: Ching-Fang Lin
  • Patent number: 7509223
    Abstract: Circuits, methods and apparatus are provided to reduce skew among signals being received by a data interface. Signal path delays are varied such that data and strobe signals received at a memory interface are calibrated or aligned with each other along a rising and/or falling edge. For example, self-calibration circuitry provides skew adjustment of each data signal path by determining one or more delays in each data signal path and strobe signal path based on relative timings of test signals. The rising or falling edges may be used for this alignment.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: March 24, 2009
    Assignee: Altera Corporation
    Inventors: Yan Chong, Chiakang Sung, Joseph Huang, Michael H. M. Chu
  • Publication number: 20090070057
    Abstract: The object of the present invention is to provide a calibration program and an electronic compass that make it possible to calibrate the output of a magnetic sensor with a small amount of computation while a user does not notice the execution of calibration. A calibration program according to an aspect of the invention includes: a step of forming at least two triangles 21 and 22 with the use of at least four outputs of a magnetic sensor in a three-dimensional space; a step of finding circles 23 and 24 circumscribed about the triangle 21 and 22, respectively; and a step of finding the intersection of normal vectors 25 and 26 each of which passes through the center of the corresponding circumscribed circle so as to find a reference point.
    Type: Application
    Filed: November 7, 2008
    Publication date: March 12, 2009
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Kisei HIROBE, Yukimitsu YAMADA, Katsuyuki KAWARADA
  • Publication number: 20090070056
    Abstract: Measurements are acquired from a magnetic sensor during a non-pre-ordered movement, and a plurality of sets of solutions are determined for respective expected values of intensity of the Earth's magnetic field. The solutions are defined by a plurality of parameters, including at least one gain value for each detection axis of the magnetic sensor. For each solution, a figure of merit is determined, correlated to a calibration error, and a partial solution is selected in each set of solutions, based on the figure of merit. Once a gain confidence interval has been defined, a calibration solution is selected based on the figure of merit, from among the partial solutions having respective gain values all falling within the gain confidence interval.
    Type: Application
    Filed: August 22, 2008
    Publication date: March 12, 2009
    Applicant: STMicroelectronics, S.r.I.
    Inventors: Francesco Vocali, Fabio Biganzoli
  • Patent number: 7493231
    Abstract: Determination of the actual position of the rotation axis of a transportation mechanism relative to a reference axis, in particular relative to gravity, is performed with at least one inclination sensor mounted to the transportation mechanism having at least one measurement axis, and comprises the measurement of the inclination of at least the one inclination sensor along the at least one measurement axis in a first rotation position of the transportation mechanism, and the measurement of the inclination of the at least one inclination sensor along the at least one measurement axis in a second rotation position. The actual position of the rotation axis of the transportation mechanism may be determined from the measurement values of the inclination sensor and the angular separation between the rotation positions. The process is suitable in particular for a process to align the rotation axis of a transportation mechanism and for a process for replacing a transportation mechanism.
    Type: Grant
    Filed: July 21, 2006
    Date of Patent: February 17, 2009
    Inventor: Ottmar Graf
  • Publication number: 20090012733
    Abstract: When an external magnetic field is applied to a sensor unit 12 for various causes, a characteristics curve does not pass through an intersection point of resistance (voltage) and a magnetic field and is offset. That is, an offset voltage (Roff) occurs. In the present invention, in order to determine a correction value for canceling the offset voltage, a difference between output voltages is determined from two stages in which a bias magnetic field is inverted, and the bias magnetic field is controlled until the difference becomes approximately zero. Then, the corresponding bias magnetic field (the electrical current value) when the difference between the output voltages becomes approximately zero is set as a correction value (correction bias). As a result, since correction can be performed even if an offset voltage is applied, it is possible to accurately perform magnetic detection.
    Type: Application
    Filed: September 5, 2008
    Publication date: January 8, 2009
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Yukimitsu Yamada, Kisei Hirobe
  • Patent number: 7474977
    Abstract: In a compass sensor unit, an azimuth data computing method is carried out by the steps of: inputting a signal from a geomagnetic sensor to measure magnetic field; determining whether to store measurement data of the magnetic field based on a distance from the last stored measurement data; calculating an offset value based on the stored data; making a comparison for each component of a plurality of measurement data used for calculating the offset value, and judging the offset value to be valid when a difference between the maximum and minimum values of each component is a given value or more; updating the already stored offset value to the offset value judged to be valid; and correcting newly provided measurement data by the updated offset value to compute azimuth data.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: January 6, 2009
    Assignee: Yamaha Corporation
    Inventors: Hideki Sato, Yukio Wakui, Masayoshi Omura
  • Publication number: 20090006020
    Abstract: In a compass sensor unit, an azimuth data computing method is carried out by the steps of: inputting a signal from a geomagnetic sensor to measure magnetic field; determining whether to store measurement data of the magnetic field based on a distance from the last stored measurement data; calculating an offset value based on the stored data; making a comparison for each component of a plurality of measurement data used for calculating the offset value, and judging the offset value to be valid when a difference between the maximum and minimum values of each component is a given value or more; updating the already stored offset value to the offset value judged to be valid; and correcting newly provided measurement data by the updated offset value to compute azimuth data.
    Type: Application
    Filed: September 8, 2008
    Publication date: January 1, 2009
    Applicant: YAMAHA CORPORATION
    Inventors: HIDEKI SATO, Yukio Wakui, Masayoshi Omura
  • Patent number: 7472032
    Abstract: A sensor array made up of 2n piezoelectric oscillators (preferably paired quartz oscillators) is provided in which n equals the number of axes of interest and each one of the pairs of oscillators has a principle axis directed oppositely from the other of its pair. A controller which preferably includes a microprocessor, makes use of the dynamic relationships of the sensors in the array to adaptively assess the magnitude of weighting factors needed to correct the output signal from each oscillator for environmental and systematic effects to provide optimum frequency and phase output for computing position, velocity, and acceleration. Preferably, a seventh reference oscillator is provided in the center of the array which is canted relative to each of the three orthogonal axes by 45°. This adaptive sensor array is capable of determining position within one meter along any of the x, y, and z axes without the need for any external (e.g., GPS) signal.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: December 30, 2008
    Assignee: Allan Space-Time Solutions, LLC
    Inventors: David W Allan, John A Kusters, Gus R German
  • Patent number: 7467061
    Abstract: In an information processing method, an orientation sensor is mounted on a targeted object to be measured, and bird's-eye view cameras for capturing images of the targeted object are fixedly installed. From the images captured by the bird's-eye view cameras, an index detecting unit detects indices mounted on the orientation sensor. A measured orientation value from the orientation sensor is input to an orientation predicting unit, and the orientation predicting unit predicts the present orientation of the targeted object based on an azimuth-drift-error correction value. A position-orientation calculating unit uses the image coordinates of the detected indices to calculate the position of the imaging device and an update value of the azimuth-drift-error correction value, which are unknown parameters. From the obtained parameters, the position-orientation calculating unit finds and outputs the position and orientation of the targeted object.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: December 16, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyohide Satoh, Shinji Uchiyama, Takaaki Endo, Masahiro Suzuki
  • Publication number: 20080289203
    Abstract: The invention relates to a method for defining a compass direction by means of an electronic compass device. In the method at least two field components of an external magnetic field are measured, from which a set of data points is formed, which correspond to the different orientations of the device relative to the external magnetic field, so that the location of the data points in a set of co-ordinates depends on the Earth's magnetic field and the magnetic disturbances of the environment. From the data points it is determined whether the set of data points correspond to a measurement, in which the device has remained on the horizontal plane with a predefined accuracy, or the tilting of the device is detected relative to the horizontal plane during measurement and the set of data points is corrected to correspond to a measurement in which the device has remained on the horizontal plane with a predefined accuracy.
    Type: Application
    Filed: May 20, 2008
    Publication date: November 27, 2008
    Inventors: Mikko Martikka, Erik Lindman
  • Patent number: 7451549
    Abstract: A magnetic compass apparatus and method to account for magnetic distortion while determining a magnetic heading is disclosed. The method enables a compass module, comprising at least two magnetometers, to characterize its magnetic environment dynamically, while collecting data of a geomagnetic field; a user moves an apparatus through various orientations; the environment may or may not contain magnetic distortion influences. Data gathered by magnetometers and, optionally, accelerometers are processed through at least two filters before being transferred as a processed data set for repetitive measurement calculations. A series of calculations is executed recursively in time by solving one or more linear vector equations using processed data.
    Type: Grant
    Filed: August 9, 2006
    Date of Patent: November 18, 2008
    Assignee: PNI Corporation
    Inventors: Raj Sodhi, Jay Prunty, George Hsu, Becky Oh
  • Patent number: 7451059
    Abstract: A method and a system are recited for obtaining a true azimuth heading for correcting a coarse azimuth heading measured from an observation position to a specific selected target by operating a data acquisition system disposed at the observation position. In principle, data is acquired and measurements are taken to allow calculation of a calculated target, including error area limits. The calculated target surrounded by error area limits is presented as a search zone to an operator for searching, finding and indicating on a display, on which is superimposed at least one map, of the specific selected target. Once found, calculations of the true azimuth are performed, allowing the derivation of the true North. The method and a system are operative with a variety of maps, including digital terrain models and stellar maps.
    Type: Grant
    Filed: July 24, 2006
    Date of Patent: November 11, 2008
    Inventors: Tomer Malchi, Yaniv Malchi
  • Patent number: 7433798
    Abstract: A solid state inclinometer sensor system includes a digital network of devices. Each device of the network includes a solid state inclinometer attached to a mounting structure. The inclinometer includes gravity sensors and a processor. The gravity sensors are mounted to provide components of earth's gravity. The processor uses data derived from the gravity sensors to calculate inclination of the mounting structure and provide a digital output for transmission on the digital network.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: October 7, 2008
    Assignee: MicroStrain, Inc.
    Inventors: Christopher P. Townsend, Steven W. Arms
  • Publication number: 20080228422
    Abstract: A calibration information calculation unit (540) calculates a plurality of candidates of first coordinate transformation information using a plurality of candidates of second coordinate transformation information, a sensor measured value, and the position and orientation of a video camera (100) on the world coordinate system. The calibration information calculation unit (540) then calculates a piece of first coordinate transformation information by combining the plurality of calculated candidates. Then, the calibration information calculation unit (540) makes iterative calculations for correcting calibration information using a candidate of the second coordinate transformation information and the first coordinate transformation information as initial values of the calibration information.
    Type: Application
    Filed: March 11, 2008
    Publication date: September 18, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Kiyohide Satoh
  • Publication number: 20080221820
    Abstract: Provided is a system for monitoring resources in a utility computing environment (UCE). Measurements are evaluated to determine whether or not a particular resource requires remedial or other type of action. A sliding measurement window is employed to assemble a number of measurements corresponding to a particular resource. The number of intervals in a sliding measurement window is based upon best practices corresponding to the resource being measured and analyzed. A first threshold-crossing event and subsequent events are stored until the window is full, or closed. When the window is closed, the threshold-crossing measurements are analyzed to determine whether or not there exists an issue with the resource that requires action. Once a window has been closed and analyzed, the first threshold-crossing event and each subsequent event up to a second threshold-crossing event are discarded and the window reopens.
    Type: Application
    Filed: May 12, 2008
    Publication date: September 11, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Rhonda L. Childress, Miguel E. Gasca, Elfred Pagan, Abigail A. Tittizer