GPS/INS

About: GPS/INS is a research topic. Over the lifetime, 3554 publications have been published within this topic receiving 62784 citations.

Fusion of Map and Sensor Data in a Modern Car Navigation System

Abstract: The main tasks of car navigation systems are positioning, routing, and guidance. This paper describes a novel, two-step approach to vehicle positioning founded on the appropriate combination of the in-car sensors, GPS signals, and a digital map. The first step is based on the application of a Kalman filter, which optimally updates the model of car movement based on the in-car odometer and gyroscope measurements, and the GPS signal. The second step further improves the position estimate by dynamically comparing the continuous vehicle trajectory obtained in the first step with the candidate trajectories on a digital map. This is in contrast with standard applications of the digital map where the current position estimate is simply projected on the digital map at every sampling instant.

Method of enhancing receiver autonomous GPS navigation integrity monitoring and GPS receiver implementing the same

Abstract: A global positioning system (GPS) receiver or navigation apparatus for use on an aircraft is disclosed. The receiver implements improved methods of performing both navigation and fault detection and exclusion (FDE) functions. The GPS receiver includes an antenna adapted to receive GPS satellite signals from each of a multiple GPS satellites. Navigation solution determining circuitry coupled to the antenna receives the GPS satellite signals and performs navigation and FDE functions. The navigation solution determining circuitry is adapted to determine both a horizontal position of a least squares navigation solution for the receiver and a horizontal position of a first navigation solution for the receiver as functions of the received GPS satellite signals. The horizontal position of the first navigation solution for the receiver is offset from the horizontal position of the least squares navigation solution for the receiver. The first navigation solution can be either of a maximal accuracy or a maximal integrity navigation solution.

GPS Navigation : Combining Pseudorange with Continuous Carrier Phase Using a Kalman Filter

Abstract: The notion of aiding GPS code-ranging information with carrier phase measurements has been around for quite some time. The integration of these two complementary forms of data can provide highly precise position solutions corrupted by very little high-frequency error, which is advantageous particularly for high- dynamical situations. This paper presents two schemes, based on the Kalman filter, for integrating GPS code and carrier measurements efficiently. One of these schemes involves a general combination of the two types of measurements, where the vehicle motion is described as a random process. In the other, the continuous carrier phase measurements provide a dynamically exact reference trajectory in much the same manner as in an inertial system, and the pseudorange data is then used to update this reference trajectory via a Kalman filter. This method of integration looks especially attractive as a means of achieving good dynamical response while still retaining the benefits of filtering the pseudorange data.

Attitude determination by integration of MEMS inertial sensors and GPS for autonomous agriculture applications

Abstract: Integration of Global Positioning System (GPS) and Inertial Navigation System (INS) technologies, which has widespread usage in industry, is also regarded as an ideal solution for automated agriculture because it fulfils the accuracy, reliability and availability requirements of industrial and agricultural applications. Agriculture applications use position, velocity and heading information for automated vehicle guidance and control to enhance the yield and quality of the crop, and in order to vary the application of fertilizer and herbicides according to soil heterogeneity at sub-field level. A loosely coupled GPS/INS integration algorithm known as "AhrsKf" is introduced for automated agriculture vehicle guidance and control utilizing MEMS inertial sensors and GPS. The AhrsKf can produce high-frequency attitude solutions for the vehicle's guidance and control system, by using inputs from a single survey grade L1/L2 antenna, eliminating the need for the previous two antenna solutions. Given its agricultural application, the AhrsKf has been implemented with some specific design features to improve the accuracy of the attitude solution including, temperature compensation of the inertial sensors, and the aid of plough lines of farm lands. To evaluate the AhrsKf solution, two benchmarking tests have been conducted by using a three-antenna GPS system and NovAtel's SPAN-CPT. The results have demonstrated that the AhrsKf solution is stable and can correctly track the movement of the farming vehicle.

Design, geometry evaluation, and calibration of a gyroscope-free inertial measurement unit

Abstract: This work reports on a gyroscope-free inertial measurement unit (GF-IMU) that only comprises linear accelerometers in order to directly measure the transversal acceleration as well as the angular acceleration and velocity. The accuracy of the calculated body motion depends on the geometrical setup and the variance of the employed accelerometers. Therefore, an analytical evaluation of the sensor placement for the propagation of the sensor variance is provided here. The positions and orientations of the sensors within the body frame have to be known precisely in order to calculate the exact inertial movement of the body. With the calibration scheme presented here it is possible to identify these parameters completely even without any previous knowledge. Furthermore, the variance of the parameters can be determined, which can be used to evaluate the performance of the calibration. Using only acceleration sensors it is not possible to determine the direction of a rotation. To overcome this drawback, an Unscented Kalman filter (UKF) is applied to merge the information of the angular acceleration and the angular rate and thus robustly estimate the sign of the angular velocity. Measurements on a 3D-rotation table were carried out to exemplarily demonstrate the accuracy improvements after the calibration. Thereby, the RMS error of the angular rate was reduced by a factor of 2.8.