Abstract: A method for obtaining, by a vehicle, information regarding its own location through V2X communication is disclosed. Specifically, the method for obtaining location information of a vehicle may comprise the steps of: receiving a V2I message including location information of a road side unit (RSU) from the RSU; receiving a V2X message including reception time information related to a time when the V2I message is received from each of a first surrounding vehicle and a second surrounding vehicle; calculating a relative position of the RSU relative to the current vehicle on the basis of the reception time information and the time at which the current vehicle received the V2I message; and acquiring the location of the current vehicle on the basis of the relative location of the RSU and the location information of the RSU.

Abstract: A physical quantity detection circuit includes an analog/digital conversion circuit having an input capacitance and sampling an analog signal in the input capacitance to convert the analog signal into a digital signal, a precharge circuit for precharging the input capacitance before the analog/digital conversion circuit sample the analog signal in the input capacitance, a digital arithmetic circuit for performing arithmetic processing to the digital signal, and a reference voltage circuit for supplying a power supply voltage to the precharge circuit and the digital arithmetic circuit, wherein the arithmetic processing start timing and the arithmetic processing end timing of the digital arithmetic circuit are set to the timings avoiding the precharge period in which the precharge circuit precharges the input capacitance.

Abstract: A clock integrated circuit is provided. The clock integrated circuit includes: a first clock generator which includes a crystal oscillator configured to generate a first clock signal; and a second clock generator which includes a resistance-capacitance (RC) oscillator and a first frequency divider, and is configured to: generate a second clock signal using the first frequency divider based on a clock signal output from the RC oscillator; perform a first calibration operation for adjusting a frequency division ratio of the first frequency divider to a first frequency division ratio based on the first clock signal; and perform a second calibration operation for adjusting the first frequency division ratio to a second frequency division ratio based on a sensed temperature.

Abstract: A vehicle includes an inertial measurement unit (IMU); and a controller electrically connected to the IMU. The controller is configured to receive an output signal including at least one of an angular velocity and an acceleration from the IMU, to identify a driving state of the vehicle according to at least one of the output signal, a steering angle of the vehicle, a steering angular velocity of the vehicle, a number of gear stages of the vehicle, a wheel speed of the vehicle, and a braking pressure of the vehicle, to identify an offset and an offset reliability of the output signal according to the driving state of the vehicle, and to transmit a signal from which the offset is removed from the output signal according to the offset and the offset reliability.

Abstract: Adjusting of calibration parameters for a sensor. The adjusted calibration parameters may be used to correct the raw data of the sensor. It is provided to calculate new calibration parameters only when accuracy of the calibration parameters currently available is no longer adequate, and suitable measurement data are available for a recalibration of the sensor. Otherwise, the components necessary for calibrating the sensor data may be deactivated in order to reduce energy consumption.

Abstract: This provides methods and systems for the global navigation satellite system (GNSS) combined with the dead-reckoning (DR) technique, which is expected to provide a vehicle positioning solution, but it may contain an unacceptable amount of error due to multiple causes, e.g., atmospheric effects, clock timing, and multipath effect. Particularly, the multipath effect is a major issue in the urban canyons. This invention overcomes these and other issues in the DR solution by a geofencing framework based on road geometry information and multiple supplemental kinematic filters. It guarantees a road-level accuracy and enables certain V2X applications which does not require sub-meter accuracy, e.g., signal phase timing, intersection movement assist, curve speed warning, reduced speed zone warning, and red-light violation warning. Automated vehicle is another use case. This is used for autonomous cars and vehicle safety, shown with various examples/variations.

Abstract: A method for calibrating an optical sensor in a Bluetooth headset and a Bluetooth headset are provided. The Bluetooth headset includes an optical sensor and a command execution device, the Bluetooth headset is connected to a charging box which is adapted to the Bluetooth headset, and a command initiation device and a command transmission medium are arranged in the charging box. With the method, if the command initiation device is triggered, the command initiation device sends a calibration command to the command execution device via the command transmission medium; and the command execution device calibrates an optical sensor in response to the calibration command to obtain a calibration result, and stores the calibration result.

Abstract: A method including receiving, in a computing device, periodic measurements of accelerations from a plurality of sensor modules. The computing device determines whether each respective sensor module of the sensor modules is attached to a respective part of a user from the periodic measurements of accelerations from the plurality of sensor modules as received. In response to the determination that each respective sensor module of the sensor modules is attached to the respective part of the user, the method includes initiating, by the computing device, a calibration operation to calibrate orientation measurements of the sensor modules relative to a common reference system defined based on an orientation of the user.

Abstract: A sensor device includes a mounting member having fixation surfaces inside, and at least one electronic component directly or indirectly fixed to the fixation surfaces of the mounting member, and the mounting member constitutes a part of a casing for housing the electronic component. Further, the fixation surfaces are perpendicular to each other.

Abstract: An external-world recognition system includes: a satellite positioning device that measures the position of a vehicle by receiving radio waves transmitted from artificial satellites; a yaw rate sensor that detects or estimates the movement of the vehicle; a camera that acquires external-world information about the surroundings of the vehicle; and an external-world recognition device that recognizes external-world information considering a reference direction as the center. The external-world recognition device corrects a detection value from the yaw rate sensor on the basis of time-series positions of the vehicle as measured by the satellite positioning device and corrects the reference direction on the basis of the corrected detection value.

Abstract: A server device can obtain historical location data, concerning a vehicle, captured by a global positioning system (GPS) device of the vehicle and historical engine control unit (ECU) data concerning the vehicle captured by an ECU of the vehicle. The server device can process the historical location data and the historical ECU data to train a machine learning model to determine a relationship between the historical location data and the historical ECU data. The server device can receive location data and ECU data concerning the vehicle and update the machine learning model based on the location data and the ECU data. The server device can receive real-time location data concerning the vehicle and derive an equivalent real-time ECU speed using the machine learning model. The server device can generate a message regarding the equivalent real-time ECU speed of the vehicle and send the message to a remote device for display.

Abstract: This provides methods and systems for the global navigation satellite system (GNSS) combined with the dead-reckoning (DR) technique, which is expected to provide a vehicle positioning solution, but it may contain an unacceptable amount of error due to multiple causes, e.g., atmospheric effects, clock timing, and multipath effect. Particularly, the multipath effect is a major issue in the urban canyons. This invention overcomes these and other issues in the DR solution by a geofencing framework based on road geometry information and multiple supplemental kinematic filters. It guarantees a road-level accuracy and enables certain V2X applications which does not require sub-meter accuracy, e.g., signal phase timing, intersection movement assist, curve speed warning, reduced speed zone warning, and red-light violation warning. Automated vehicle is another use case. This is used for autonomous cars and vehicle safety, shown with various examples/variations.

Abstract: A fuel efficiency estimation system includes: a velocity profile calculation unit to calculate a velocity profile indicating a change in velocity of a motor vehicle traveling a traveling route; a velocity disturbance calculation unit to calculate, based on disturbance information indicating a disturbance event occurring on the traveling route and traveling history information collected from the motor vehicle traveling the traveling route, an attenuation factor, which is a ratio of attenuation of the velocity of the motor vehicle traveling the traveling route, as a velocity disturbance correction coefficient; and a fuel efficiency calculation unit to calculate fuel efficiency of the motor vehicle traveling the traveling route by using the velocity profile and the velocity disturbance correction coefficient.

Abstract: A driving circuit for a microelectromechanical system (MEMS) gyroscope operating based on the Coriolis effect is provided. The driving circuit supplies drive signals to a mobile mass of the MEMS gyroscope to cause a driving movement of the mobile mass to oscillate at an oscillation frequency. The driving circuit includes an input stage, which receives at least one electrical quantity representing the driving movement and generates a drive signal based on the electrical quantity; a measurement stage, which measures an oscillation amplitude of the driving movement based on the drive signal; and a control stage, which generates the drive signals based on a feedback control of the oscillation amplitude. The measurement stage performs a measurement of a time interval during which the drive signal has a given relationship with an amplitude threshold, and measures the oscillation amplitude as a function of the time interval.

Abstract: A shift range control device includes an angle calculation unit, a target angle setting unit, a learning unit and a drive control unit. The learning unit learns a correction value to be used in calculating a motor angle target value based on a motor angle and an output shaft signal. The learning unit learns the correction value based on at least a first change point value, which is the motor angle at a timing at which the output shaft signal changes when a rotation member rotates in a first direction from a state in which an engagement member is in the center of valley section, and/or a second change point value, which is the motor angle at a timing at which the output shaft signal changes when the rotation member rotates in a second direction from a state in which the engagement member is in the center of the valley section.

Abstract: A wheel speed estimation device is to be applied to a four-wheel drive vehicle including a first coupling device for a rear left-wheel axle and a second coupling device for a rear right-wheel axle. These coupling devices respectively change states of engagement of a left engagement state and a right engagement state to the any one of a completely restraint state, a release state, and an incompletely restraint state. The wheel speed estimation device includes a correction parameter calculator that calculates correction parameters affected by a difference in wheel radius between wheels based on all wheel rotation speed signals, and a wheel speed calculator that calculates wheel speeds based on the wheel rotation speed signals and the correction parameters. Further, the correction parameter calculator stops calculation of the correction parameters when at least one of the left engagement state or the right engagement state is the incompletely restraint state.

Abstract: A method includes receiving a signal from a sensor. The signal includes a first in-phase component and a first quadrature component. The first in-phase and quadrature components are identified. A rate signal is applied to the sensor and the sensor generates a sensed rate signal. A second in-phase and quadrature components associated with the sensed rate signal are determined. A phase error based on the first and the second in-phase components, and the first and the second quadrature components is determined. The method may further include reducing error in measurements associated with the sensor by dynamically compensating for the determined phase error, e.g., by modifying a clock signal, by changing a demodulation phase of a demodulator used to identify the in-phase and the quadrature components.

Abstract: A method is disclosed for managing an internet connection and informing a user about connectivity to the internet of a user terminal via a gateway, the gateway being connected to the user terminal via a local area network and to an internet service provider via a broadband line. The method includes: remotely provisioning through the first communication link the configuration of the gateway for internet connection; detecting completion of configuration of the gateway for internet connection in accordance with a service subscribed by the user, determining the state of the broadband line; and providing the user with a visual indication of availability of connectivity to the internet when configuration of the gateway for internet connection is completed and the broadband line is active; and managing the activation and deactivation of the connection to the internet by user terminals connected to a gateway via the local area network.

Abstract: A washing machine appliance, including methods of operation, is provided herein. The washing machine appliance may include a cabinet, a tub, and a rotation element mounted therein. The method may include flowing a volume of liquid into the tub; rotating the rotation element within the tub; measuring an angular position of the cabinet relative to a fixed axis after the flowing; comparing the measured angular position of the cabinet to a predetermined threshold; and adjusting a voltage within the washing machine appliance in response to the measured angular position exceeding the predetermined threshold.

Abstract: Described techniques enable resource accounting and tracking in high access rate systems using low cost memories. A first set of counters is maintained in relatively lower cost memory. The first counters generally indicate the amount of resources used for each object in a set of objects, but on a potentially delayed basis. A second set of counters of smaller size is stored in a relatively higher cost memory that supports high arrival and departure rates for accurate accounting. Each second counter indicates the amount of resources assigned (or unassigned) to an object since the object's first counter was last updated, and is incremented or decremented whenever this amount changes. A background process is configured to update individual first counters from the corresponding second counters on a recurring basis. The exact times at which a given first counter is updated may vary in accordance with a variety of approaches.

Abstract: A method and system are provided for determining a heading angle of a user of a portable electronic device in an indoor environment. In an embodiment, the device collects rotational movement information indicative of rotational movement of the device and determines a first heading angle of the device. The first heading angle is determined by using the downward direction of the device to determine the vertical angular rate in the horizontal plane, and integrating the vertical angular rate to form the first heading angle. The device collects first direction information from a first direction sensor and second direction information from a second direction sensor and uses it determine which of the first and second direction information is an outlier, e.g., inaccurate due to an occurrence of a disturbance. The device then corrects the heading angle by comparing the heading angle to the first and second direction information.

Abstract: Disclosed herein are example embodiments for unoccupied flying vehicle (UFV) location assurance. For certain example embodiments, at least one machine, such as a UFV, may: (i) obtain one or more satellite positioning system (SPS) coordinates corresponding to at least an apparent location of at least one UFV; or (ii) perform at least one analysis that uses at least one or more SPS coordinates and at least one assurance token. However, claimed subject matter is not limited to any particular described embodiments, implementations, examples, or so forth.

Abstract: An activity tracking device, such as a step-counting device includes an interface configured to receive one or more acceleration signals and signal processing circuitry. The signal processing circuitry generates an indication of condition of an accelerometer, such as a body position of the accelerometer, based on one or more accelerometer signals, generates an event signal, such as an event flag, based on one or more accelerometer signals and the indication of the condition of the accelerometer, and generates an activity signal, such as step flag based on the event signal, the indication of the condition of the accelerometer and one or more acceleration signals. The signal processing circuitry may generate a noise signal based on one or more acceleration signals and generate the activity signal based on the noise signal.

Abstract: An electronic device comprising: a sensor; a communication unit; and at least one processor configured to: receive a first speed measurement from the sensor; receive, via the communication unit, speed information transmitted by an external device; calculate at least one correction parameter based on the first speed measurement and the speed information; and adjust a second speed measurement that is received from the sensor based on the correction parameter.

Abstract: A hand-held processor system for processing data from an integrated MEMS device disposed within a hand-held computer system and method. A dynamic offset correction (DOC) process computes 3-axis accelerometer biases without needing to know the orientation of the device. Arbitrary output biases can be corrected to ensure consistent performance A system of linear equations is formed using basic observations of gravity measurements by an acceleration measuring device, conditioned upon constraints in data quality, degree of sensed motion, duration, and time separation. This system of equations is modified and solved when appropriate geometric diversity conditions are met.

Abstract: Athletic activity may be tracked and monitored while providing encouragement and maintaining an individual's interest in continuing to perform athletic activity. For example, energy expenditure values and energy expenditure intensity values may be calculated based on the duration and type of activity performed by an individual. These values and other movement data may be displayed on an interface in a manner to motivate the individual and maintain the individual's interest. Other individuals (e.g., friends) may also be displayed on an interface through which a user's progress is tracked. This may allow the user to also view the other individuals' progress toward completing an activity goal and/or challenge.

Abstract: A method includes receiving a signal from a sensor. The signal includes a first in-phase component and a first quadrature component. The first in-phase and quadrature components are identified. A rate signal is applied to the sensor and the sensor generates a sensed rate signal. A second in-phase and quadrature components associated with the sensed rate signal are determined. A phase error based on the first and the second in-phase components, and the first and the second quadrature components is determined. The method may further include reducing error in measurements associated with the sensor by dynamically compensating for the determined phase error, e.g., by modifying a clock signal, by changing a demodulation phase of a demodulator used to identify the in-phase and the quadrature components.

Abstract: Athletic activity may be tracked and monitored while providing encouragement and maintaining an individual's interest in continuing to perform athletic activity. For example, energy expenditure values and energy expenditure intensity values may be calculated based on the duration and type of activity performed by an individual. These values and other movement data may be displayed on an interface in a manner to motivate the individual and maintain the individual's interest. Other individuals (e.g., friends) may also be displayed on an interface through which a user's progress is tracked. This may allow the user to also view the other individuals' progress toward completing an activity goal and/or challenge.

Abstract: The described positional awareness techniques employing visual-inertial sensory data gathering and analysis hardware with reference to specific example implementations implement improvements in the use of sensors, techniques and hardware design that can enable specific embodiments to provide positional awareness to machines with improved speed and accuracy.

Abstract: The present disclosure describes systems and methods for maintaining gyroscopic sensor accuracy over time and across changing environmental conditions. In certain aspects, the present disclosure provides arrangements and methods for calibrating a gyroscope while it is positioned on a robotic platform. In particular, the gyroscope may positioned on a sensor platform that is moved through a series of known or measured rotations and then the gyroscope signals are compared to reference data and the sensor's gain and offset calculated. In other aspects, the present disclosure provides arrangements and methods for utilizing measurements from multiple gyroscopes that measure the same axis of rotation.

Abstract: Systems, apparatus and methods to supplement, combine, replace, verify and calibrate in-vehicle and in-device sensors and GNSS systems are presented. A mobile device and a vehicle navigation system share sensor and GNSS information to arrive at an improved navigation solution. For example, a navigation solution computed by a vehicle may rely on a sensor signal from a mobile device. Similarly, a navigation solution computed by a mobile device may use a sensor signal or a GNSS signal from a vehicle.

Abstract: The described positional awareness techniques employing visual-inertial sensory data gathering and analysis hardware with reference to specific example implementations implement improvements in the use of sensors, techniques and hardware design that can enable specific embodiments to provide positional awareness to machines with improved speed and accuracy.

Abstract: A target vehicle speed generating device basically includes a determination unit and a correction unit. The determination unit determines whether or not a sudden change point is present in the target vehicle speed contained in the corrects the target vehicle speed so as to eliminate the sudden change point upon determining that the sudden change point is present by the determination unit. The sudden change point corresponds to a point at which acceleration changes in excess of a predetermined condition.

Abstract: A method implementing an accelerometer for analyzing biomechanical parameters of a runner's stride. The method includes fastening a device (1) on the runner that has a triaxial accelerometer (17), a chronograph (16), a digital processor (19) and a display (11). The method measures a sequence of acceleration data in at least the vertical direction using the accelerometer, while the runner runs a certain distance (D) along a running course. During or at the end the running course, the processor calculates the biomechanical parameters of the stride, including lowering the center of gravity and/or the elevation (E) of the center of gravity and/or the sum of the lowering and of the elevation (E) and/or the vertical mechanical work of the center of gravity, based on the acceleration data, of the distance (D) and a period of time measured by the chronograph (16); and displays the parameters.

Abstract: A method is provided for calibrating an inertial sensing unit of a device utilizing a vision sensing unit integral to the device. The method includes receiving inertial sensing input data from the inertial sensing unit, receiving vision sensing input data from the vision unit, and determining when the received vision sensing input data represents a predetermined input state of the vision sensing unit. The method includes estimating an error value in the inertial sensing input data received from the inertial sensing unit based on the received vision sensing input data upon determination that the received vision sensing input data represents the predetermined vision sensing input state. The method further includes adjusting first subsequent received inertial sensing input data from the inertial sensing unit based on the estimated error value, thereby calibrating the inertial sensing unit.

Abstract: A SBW-ECU switches over a shift range to a selected range by rotationally driving a motor to a target position corresponding to the selected range. When a direction of rotation of the motor is the same as a direction toward the target position and a difference between the target position and a present position is larger than a threshold value in a case that the selected range is changed during rotational driving of the motor, the target position is updated to a post-change target position. When the direction of rotation of the motor is opposite to the direction toward the target position or the difference between the target position and the present position is smaller than the threshold value in the case that the selected range is changed during rotational driving of the motor, the target position is updated to the post-change target position after completing the switchover to the pre-change selected range.

Abstract: A controller for controlling a plurality of lighting devices configured for wireless communications in a facility includes a data communications interface communicating with at least one of the devices. The controller further includes a control module configured to provide a control signal to the data communications interface for communicating to a transceiver associated with the device and for turning off the device according to an algorithm wherein the control signal is provided based on a time of day and/or a sensed condition relating to use of the facility. The transceiver reports device data to the control module to quantify a reduction in power obtained by controlling the devices according to the algorithm.

Abstract: A system (40) for calibrating an inertial sensor (20) includes a power source (42), a frequency measurement subsystem (44, 48), and a gain determination subsystem (52). A calibration process (110) using the system (40) entails applying (116) a bias voltage (66) to the inertial sensor (20), measuring (114) a drive resonant frequency (46), and measuring (118) a sense resonant frequency (50) of the inertial sensor (20) produced in response to the bias voltage (66). A gain value (32) is determined (124) for calibrating (144) the inertial sensor (20) using a relationship (140) between the sense resonant frequency (50) and the bias voltage (66) without imposing an inertial stimulus on the inertial sensor (20).

Abstract: A measuring device includes a pair of sensors, an actuator, a noise extraction unit and a low frequency noise (LFN) estimator. The sensors each generate with sample time Ts a sense signal indicating a value of a component of a vectorial physical quantity. The sensors have an Allan variance curve with a minimum value for a first integration time T1. The curve has a first and second tangent line being tangent at integration time 0, and integration time T1 respectively. The tangent lines intersect each other at an intersection point for a second integration time T2. The estimator having an effective integration time Teff determined by, Ts, T1 and T2, generates an estimated noise signal indicative for the estimated value of the noise component from the difference signal and from information about the relative rotation between the sensors.

Abstract: A method and system for determining an alignment error between sensors mounted to a machine is disclosed. The method may include calculating a first orientation value based on a signal received from a first sensor. The method may further include calculating a second orientation value based on a signal received from a second sensor. The method may further include calculating an alignment error between the first sensor and the second sensor based on a difference between the first orientation value and the second orientation value.

Abstract: A gyroscopic rotational monitoring system may be utilized for monitoring one or more properties of rotatable container or vessel, and/or one or more properties of a displaceable material contained in the rotatable vessels. An exemplary aspect relates to the use of a gyroscope and periodicity sensor (e.g., accelerometer) to determine rotational speed of a concrete mixing drum, so that the slump or other property of the concrete can be monitored or adjusted such as by dosing with water, chemical admixtures, or mixture thereof.

Abstract: A learning processing unit derives, using learning data in which a characteristic value based on a distribution coordinate of a detected acceleration by an acceleration sensor which configured to be worn on a body of a user is associated with a moving speed of the user, a moving speed relational expression for finding an estimated speed from the characteristic value. A moving speed estimation unit finds an estimated speed from a current characteristic value using the derived moving speed relational expression.

Abstract: An inclination angle compensation system for determining an inclination angle of a machine is disclosed. The inclination angle compensation system may have a non-gravitational acceleration estimator configured to estimate a non-gravitational acceleration of a machine based on an estimated inclination angle and an acceleration output from a forward acceleration sensor. The inclination angle compensation system may also have an inclination angle sensor corrector configured to receive an inclination angle output from an inclination angle sensor, determine an inclination angle sensor acceleration based on the inclination angle output, and calculate a corrected inclination angle of the machine based on the non-gravitational acceleration and the inclination angle sensor acceleration.

Abstract: Embodiments of the present invention include an occupancy sensing unit configured to monitor an environment illuminated by a lighting fixture. An inventive occupancy sensing unit may include an occupancy sensor to detect radiation indicative of at least one occupancy event in the environment illuminated by the lighting fixture according to sensing parameters. The occupancy sensor can be coupled to a memory that logs sensor data, which represent the occupancy events, provided by the occupancy sensor. A processor coupled to the memory performs an analysis of the sensor data logged in the memory and adjusts the sensing parameters of the occupancy sensor based on the analysis.

Abstract: A circuit for processing signals from a gyroscope includes a first that generates an in-phase demodulated signal and a second demodulator that generates a quadrature-phase demodulated signal with reference to in-phase and quadrature-phase modulated signals, respectively, from the gyroscope. The circuit includes a digital processor that receives the demodulated in-phase and quadrature phase signals from the demodulators and generates an output signal corresponding to a rotation of the gyroscope along a predetermined axis with reference to the in-phase demodulated signal and the quadrature-phase demodulated signal to remove a portion of the quadrature-phase signal from the in-phase signal.

Abstract: A personal navigation device configured to determine heading readings continuously using data from a sensor in the personal navigation device. Heading readings are selected corresponding to a periodic event. A representative heading is determined from the selected heading readings. When a portion of the selected heading readings has a value within a range of the representative heading, a static heading indicator is asserted to indicate the personal navigation device is moving in a static heading. The static heading indicator may be used to smooth an estimated trajectory of the personal navigation device.

Abstract: A system has at least one sensor and a controller communicatively coupled to the sensor. The system further has logic configured to calculate a calibration value based upon an initial state of the sensor and store the calibration value in memory.

Abstract: A device for verifying the integrity of an item of data displayed on a display device controlled by a video controller, the video controller being connected to the display device by an appropriate connection and transmitting to it a video signal including an input interface which allows the device to be connected at a branch of the connection between the video controller and the display device, a reconstruction device which is capable, from the derived video signal, of reconstructing an image corresponding to the image displayed on the display device; an analysis device which is capable of extracting an item of reconstructed data from the reconstructed image, a comparison device which is capable of comparing the reconstructed data with a reference value of the item of data to be displayed and an alarm means which is capable of activating a malfunction alarm in accordance with the result at the output of the comparison device.

Abstract: Sensors in one or more remote devices provide sensor output to a device having a controller. The controller analyzes the sensor data to determine the accuracy of the sensors outputting the sensor data. Based on the analysis, the controller calculates a calibration value to utilize in calibrating one or more of the sensors in the remote devices, or in one or more other devices.

Abstract: A system and method for determining errors and calibrating to correct errors associated with field sensors, including bias, scale, and orthogonality, includes receiving and providing to a processor angular rate data and a first field vector relative to a first reference directional field and a second field vector relative to a second reference field from at least one field sensor. The processor is configured to relate the first field vector and the second field vector to the angular rate data to determine an error of the at least one field sensor. The processor is also configured to identify a compensation for the error of the at lease one field sensor needed to correct the first field vector and the second field vector and repeat the preceding to identify changes in the error over time and compensate for the changes in the error over time.