An apparatus and method for measuring a velocity of a moving object in a navigation system are provided, which can increase an accuracy of velocity measurement and position estimation of the moving object are provided. The apparatus includes a sensor part including an acceleration sensor for measuring acceleration of the moving object and outputting a corresponding acceleration measurement value, and includes an altimeter for measuring an altitude of the moving object and outputting a corresponding altitude measurement value; and a calculation part for calculating the velocity of the moving object by using the acceleration measurement value output from the acceleration sensor and the altitude measurement value output from the altimeter.

A strict reverse navigation method for optimal estimation of fine alignment is provided. The strict reverse navigation method including: establishing an adaptive control function; performing a forward navigation calculation process; performing a reverse navigation calculation process; and performing the adaptive control for a number of forward and reverse calculations. The strict reverse navigation method shortens an alignment time for the optimal estimation of fine alignment while ensuring an alignment accuracy. The strict reverse navigation method provided effectively solves a problem that an error of an initial value of filtering in an initial stage of the optimal estimation of fine alignment affects convergence speeds of subsequent stages. In the initial stage, a larger number of the forward and reverse navigation calculations are adopted to reduce an error of the initial value as much as possible and increase a convergence speed of the filtering.

Methods, systems, computer-readable media, and apparatuses for vehicular navigation are presented. Some configurations include computing a first attitude of a vehicle with respect to a reference frame at a first epoch; based on measurement data from an inertial navigation system (INS) of the vehicle, computing an attitude of the INS at a second epoch that is subsequent to the first epoch; based on the computed attitude of the INS and the computed first attitude of the vehicle, computing a second attitude of the vehicle at the second epoch; applying a constraint to the computed second attitude of the vehicle to produce an updated second attitude of the vehicle; and based on the updated second attitude of the vehicle, computing an updated attitude of the INS. Applications relating to road vehicular (e.g., automobile) use are described.

A posture calculation device of working machinery includes: a measuring device configured to detect an angle speed and acceleration; a posture angle calculation unit configured to obtain a posture angle of the working machinery from the detected angle speed and the detected acceleration; a first complementary filter to which a first cutoff frequency is set and configured to decrease a noise included in the obtained posture angle to output a first posture angle; a second complementary filter to which a second cutoff frequency different from the first cutoff frequency is set and configured to decrease a noise included in the obtained posture angle to output a second posture angle; and a switching unit configured to switch between the first posture angle and the second posture angle to output the first posture angle or the second posture angle according to a state of the measuring device.

A posture computing apparatus for a work machine includes a detection apparatus that is provided to the work machine and detects angular velocity and acceleration; a first posture angle computing unit that is provided to the detection apparatus and obtains a posture angle of the work machine from the angular velocity and the acceleration detected by the detection apparatus; a low-pass filter that allows the posture angle obtained by the first posture angle computing unit to pass therethrough to output the posture angle as a first posture angle; a second posture angle computing unit that outputs, as a second posture angle, a posture angle obtained from the angular velocity and the acceleration detected by the detection apparatus; and a selecting unit that outputs the first posture angle and the second posture angle in a switching manner, based on information about a change in an angle of the work machine.

The present invention discloses a method for real-time positioning of a smart device, comprising: getting tri-axial acceleration sequences truncated in turn by using a preset time period in the world coordinate individually; acquiring a dominate frequency f.sub.step by applying fast Fourier transform (FFT) on the truncated Z-axis acceleration sequence, using a band-pass filter with a pass band [f.sub.step−0.5 Hz, f.sub.step+0.5 Hz] to filter the truncated tri axial acceleration sequences individually; comparing the time domain waveform form from the filtered Z-axis acceleration sequence with a preset step threshold, and counting each peak above the threshold as a step to acquire a user's step number in the present time period; determining the moving direction of the smart device in the time period by calculating the filtered X-axis and Y-axis acceleration sequences; determining the current position of the smart device by calculating the user's step number and the moving direction of the smart device.

A system and methods are disclosed for providing the location of a tunnel boring machine (TBM) by establishing of a plurality of known locations or “monuments”; from these monuments located at least on, over or within the TBM's start point, known in the art as a “pit”. The present invention provides among other things an integrated navigation system that provides real-time parametric guidance information to the TBM, relative to the tunnel origin, past course and current trajectory, while simultaneously employing a non-contact measuring system in concert with said origin and course information for the final provision of an as-built map of tunnel dimensions and centerline.

An inertial navigation device error correction system includes an inertial navigation device, a coordinate calculation device, and an error correction device mounted on each of aerial vehicles. The coordinate calculation device calculates coordinates of a second aerial vehicle with respect to a first aerial vehicle. The error correction device calculates azimuth and elevation angles of the second aerial vehicle based on first data on the first aerial vehicle, and azimuth and elevation angles of the second aerial vehicle based on second data on the second aerial vehicle. The error correction device corrects an error caused in the inertial navigation device of the first aerial vehicle, on the basis of angle measurement residuals that are differences between the azimuth and elevation angles of the second aerial vehicle based on the first data and the azimuth and elevation angles of the second aerial vehicle based on the second data.

A system and to a method of analyzing and monitoring interfering movements of an inertial unit of an aircraft during a stage of statically aligning the inertial unit. During the static alignment stage, measurements of the velocity of the aircraft relative to the ground are acquired, and states of a mirror process having a model that is close to the model of the process of aligning the inertial unit are estimated. The states of the mirror process are estimated from observations constituted by the measurements of velocity relative to the ground. Finally, the estimates of the states are compared with respective validation thresholds in order to validate or not validate said alignment of the inertial unit.

The present disclosure relates to a gyro sensor calibration method based on vehicle velocity, which can extract a weighting factor in consideration of vehicle velocity, apply the extracted weighting factor to an extended Kalman filter, and accurately calibrate a gyro sensor in real time, in order to prevent accumulation of scale factor calibration errors, which may occurs as a turning radius is changed depending on vehicle velocity in a turning section, when a GNSS-based dead reckoning (DR) system calibrates a scale factor of the gyro sensor through the extended Kalman filter using GNSS information received in the turning section.