Various embodiments of the invention provide for automatic, real-time bias detection and error compensation in inertial MEMS sensors often used in handheld devices. Real-time bias correction provides for computational advantages that lead to optimized gyroscope performance without negatively affecting user experience. In various embodiments, bias non-idealities are compensated by utilizing raw output data from the gyroscope itself without relying on additional external sensors.

This disclosure relates to heading misalignment estimation with a portable device and more specifically to estimating misalignment between a portable device having a sensor assembly and a platform transporting the portable device when the platform is undergoing motion having periodic characteristics. In one aspect, a suitable method includes obtaining inertial sensor data for the portable device and determining an effective frequency characteristic of the inertial sensor data representing the motion having periodic characteristics. The inertial sensor data may be processed using the determined frequency characteristic so that a heading misalignment may be estimated between the heading of the portable device and the platform.

A thermal stabilization system stabilizes inertial measurement unit (IMU) performance by reducing or slowing operating variations over time of the internal temperature. More specifically, a thermoelectric heating/cooling device operates according to the Peltier effect, and uses thermal insulation and a mechanical assembly to thermally and mechanically couple the IMU to the thermoelectric device. The thermal stabilization system may minimize stress on the IMU and use a control system to stabilize internal IMU temperatures by judiciously and bidirectionally powering the thermoelectric heating/cooling device. The thermal stabilization system also may use compensation algorithms to reduce or counter residual IMU output errors from a variety of causes such as thermal gradients and imperfect colocation of the IMU temperature sensor with inertial sensors.

Systems and methods for predicting aircraft navigation performance are provided. In one embodiment, a method can include determining that one or more navigational aid measurements are not available to the aircraft. The method can include estimating a future actual navigation performance of the aircraft for a future point in the flight plan. The method can include determining a future required navigation performance associated with the future point in the flight plan. The method can include comparing the future actual navigation performance to the future required navigation performance to determine if the future actual navigation performance satisfies the future required navigation performance. The method can include providing, to an onboard system of the aircraft, information indicative of whether the future actual navigation performance satisfies the future required navigation performance.

A system and method for correcting bias and angle misalignment errors in the angle rate and acceleration outputs from a 6-DOF IMU mounted to a vehicle. The method includes providing velocity and estimation attitude data in an inertial frame from, for example, a GNSS/INS, and determining an ideal acceleration estimation and an ideal rate estimation in a vehicle frame using the velocity and attitude data. The method then determines the IMU bias error and misalignment error using the ideal acceleration and rate estimations and the angle rate and acceleration outputs in an IMU body frame from the IMU.

A method of characterizing an inertial measurement unit includes a block carrying one accelerometer positioned on an axis of a measurement reference frame and having one gyro arranged to determine the orientation of the frame relative to an inertial reference frame. The method includes keeping the inertial measurement unit centered on a point that is stationary relative to the ground and that is in a predetermined environment, to obtain accelerometer signals that are images of at least one component of the specific force vector in the measurement reference frame and also gyro signals that are images of at least one component of the instantaneous rotation of the measurement reference frame; processing the signals to obtain data representative of projecting of the specific force vector into the inertial reference frame, after compensating for rotation of the Earth; and calculating Allan variance on the data and comparing it with reference data.

An Inertial Measurement Unit (IMU), method, and navigation system are disclosed. For example, the method includes receiving a plurality of sensor values from an IMU, loading the plurality of sensor values and a plurality of true sensor values into a deep learning algorithm, and training the deep learning algorithm to enhance the accuracy of the plurality of sensor values utilizing the plurality of true sensor values.

A measurement unit comprising at least two elements, namely a block and an inertial sensor, a first of the elements being provided with studs, each having a surface against which a bearing surface of a second of the elements is applied under a force substantially normal to said surfaces, which force is exerted by at least one clamping element, the studs being of dimensions and shape adapted: to allow the studs to deform under the effect of a thermomechanical stress occurring in an operating temperature range of the measurement unit so as to avoid any slip of said surfaces relative to one another under the effect of that stress; and to keep the inertial sensor in position while ensuring that any transmission of vibration is limited and compatible with the operation of the sensor.

A high-temperature miniaturized resonant gyroscope, which comprises a resonator, a circuit board, a piezoelectric element, a supporting base, a shell and a binding post, wherein the resonator is arranged in the shell and connected with the supporting base, the piezoelectric element is connected with the binding post through a metal conductor, and key process points of internal elements of the gyroscope are fixedly connected by high-temperature materials and high-temperature processes. The gyroscope is a small-sized gyroscope capable of working at a high temperature; the present disclosure also provides an inertial navigation system, which comprises a triaxial gyroscope, a triaxial accelerometer and a damper, wherein the gyroscope is fixedly connected with the damper, and the gyroscope adopts the high-temperature resonant gyroscope. A drilling measurement system and a measurement method.

A method of characterizing an inertial measurement unit includes a block carrying one accelerometer positioned on an axis of a measurement reference frame and having one gyro arranged to determine the orientation of the frame relative to an inertial reference frame. The method includes keeping the inertial measurement unit centered on a point that is stationary relative to the ground and that is in a predetermined environment, to obtain accelerometer signals that are images of at least one component of the specific force vector in the measurement reference frame and also gyro signals that are images of at least one component of the instantaneous rotation of the measurement reference frame; processing the signals to obtain data representative of projecting of the specific force vector into the inertial reference frame, after compensating for rotation of the Earth; and calculating Allan variance on the data and comparing it with reference data.