Inertial navigation system

About: Inertial navigation system is a research topic. Over the lifetime, 14582 publications have been published within this topic receiving 190618 citations. The topic is also known as: intertial guidance system & inertial reference platform.

Hybrid inertial navigation system with improved integrity

Abstract: The invention relates to an internal platform hybridized with a GPS receiver. The hybridization is achieved through a Kalman filter through which a new hybrid position D-HYB is estimated on the basis of a noted deviation between pseudo-distance measure by the receiver between the receiver and the various satellites and corresponding distances computed by the inertial platform between the platform and the same satellites. In this filtering, the distance increment from one measurement instant to the next instant, between the pseudo-distance previously measured by the receiver on a satellite axis of a deviation and the new pseudo-distance measured by the receiver on a satellite axis of a deviation and the new pseudo-distance measured by the receiver on this axis, is the phase variation ΔΦ=Φ(t)−ΦI (t−1) of a digital oscillator between the two measurement instants, this variation being referred to distance along the satellite axis. The oscillator is that which makes it possible to slave the local carrier frequency in the receiver to the carrier frequency received from the satellite. Application to the measurement of position.

Multi-rate fusion with vision and inertial sensors

Abstract: This work presents a multi-rate fusion model, which exploits the complimentary properties of visual and inertial sensors for egomotion estimation in applications such as robot navigation and augmented reality. The sampling of these two sensors is described with size-varying input and output equations without assumed synchronicity and periodicity of measurements. Data fusion is performed with two different multi-rate (MR) filter models, an extended (EKF) and an unscented Kalman filter (UKF). A complete dynamic model for the 6D-tracking task is given together with a method to calculate the dependencies of the covariance matrices. It is further shown that a centripetal acceleration model and the precise description of quaternion prediction for a constant velocity model highly improve the estimation error for rotary motions. The comparison demonstrates that the MR-UKF provides better estimation results at higher computational costs.

Redundant MEMS-IMU integrated with GPS for performance assessment in sports

Abstract: In this article, we investigate two different algorithms for the integration of GPS with redundant MEMS-IMUs. Firstly, the inertial measurements are combined in the observation space to generate a synthetic set of data which is then integrated with GPS by the standard algorithms. In the second approach, the method of strapdown navigation needs to be adapted in order to account for the redundant measurements. Both methods are evaluated in experiments where redundant MEMS-IMUs are fixed in different geometries: orthogonally-redundant and skew-redundant IMUs. For the latter configuration, the performance improvement using a synthetic IMU is shown to be 30% on the average. The extended mechanization approach provides slightly better results (about 45% improvement) as the systematic errors of the individual sensors are considered separately rather than their fusion when forming compound measurements. The maximum errors are shown to be reduced even by a factor of 2.

Self-contained positioning method and system thereof for water and land vehicles

Abstract: A positioning method and system for water and land vehicles is disclosed for highly accurate and self-contained operation. In which, an inertial navigation system (INS) is built on the micro MEMS (MicroElectroMechanicalSystem) IMU that is the core of the position determination system. To compensate the error of the INS, multiple navigation sensors are integrated into the system. The magnetic sensor is used as a magnetic field sensor to measure the heading of the vehicle. The odometer is used to measure the distance when the vehicle is on land. An automated Zero velocity updating method is used to calibrate the ever increasing INS errors. When the vehicle is in the water, a velocimeter is used to measure water speed for the INS aiding.

A Tightly-Coupled GPS/INS/UWB Cooperative Positioning Sensors System Supported by V2I Communication

Abstract: This paper investigates a tightly-coupled Global Position System (GPS)/Ultra-Wideband (UWB)/Inertial Navigation System (INS) cooperative positioning scheme using a Robust Kalman Filter (RKF) supported by V2I communication. The scheme proposes a method that uses range measurements of UWB units transmitted among the terminals as augmentation inputs of the observations. The UWB range inputs are used to reform the GPS observation equations that consist of pseudo-range and Doppler measurements and the updated observation equation is processed in a tightly-coupled GPS/UWB/INS integrated positioning equation using an adaptive Robust Kalman Filter. The result of the trial conducted on the roof of the Nottingham Geospatial Institute (NGI) at the University of Nottingham shows that the integrated solution provides better accuracy and improves the availability of the system in GPS denied environments. RKF can eliminate the effects of gross errors. Additionally, the internal and external reliabilities of the system are enhanced when the UWB observables received from the moving terminals are involved in the positioning algorithm.