GPS/INS

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

Tightly coupled integration of multi-GNSS PPP and MEMS inertial measurement unit data

Abstract: Precise point positioning (PPP) using the Global Positioning System (GPS) is widely recognized as an efficient approach for providing precise positioning services. However, its accuracy and reliability could be significantly degraded by unexpected observation discontinuities and unfavorable tracking geometry which are unavoidable, especially in severe environments such as city canyons. Therefore, in the last decades inertial navigation system (INS) has been integrated to overcome such drawbacks. Recently, multi-Global Navigation Satellite Systems (GNSS) were applied to enhance the PPP performance by appropriate usage of the increased number of satellites. We present a new approach to tightly integrate the multi-GNSS PPP and INS together in the observation level. The inter-system bias and inter-frequency bias of multi-GNSS and the hardware errors of INS sensors are estimated to improve the position accuracy and to shorten the convergence time of PPP. In order to demonstrate the impact of multi-GNSS observations and INS data on the derived position, velocity, attitude, and the convergence time of PPP, the new approach is validated through an experimental test with a set of land vehicle data. The results show that the position accuracy can be improved by multi-GNSS and INS significantly, but very little improvement in velocity and attitude is achieved. The position root-mean-square improves from 23.3, 19.8, and 14.9 cm of the GPS PPP/INS tightly coupled integration (TCI) solution to 7.9, 3.3, and 5.1 cm of multi-GNSS PPP/INS TCI in north, east, and up components, respectively. Furthermore, GNSS outages are simulated and their effect on the performance of multi-GNSS PPP/INS TCI is investigated to demonstrate the contribution of the multi-GNSS PPP/INS TCI during GNSS outages. In addition, the convergence test also shows that both multi-GNSS and INS can improve the PPP convergence performance noticeably.

UAV attitude, heading, and wind estimation using GPS/INS and an air data system

Abstract: A new attitude, heading, and wind estimation algorithm is proposed, which incorporates measurements from an air data system to properly relate predicted attitude information with aircraft velocity information. Experimental Unmanned Aerial Vehicle (UAV) flight data was used to validate the proposed approach. The experimental results demonstrated effective estimation of the roll, pitch, yaw, and heading angles, and provided a smoothed estimate of the angle of attack and sideslip angles. The wind estimation results were validated with respect to measurments provided by a local weather station. It was shown that this new method of attitude estimation is effective in distinguishing the yaw and heading angles of the aircraft, properly regulating the attitude estimates with air data system measurements, and provding a reasonable estimate of the local wind field.

Enhanced, Delay Dependent, Intelligent Fusion for INS/GPS Navigation System

Abstract: Low-cost navigation systems, deployed for ground vehicles' applications, are designed based on the loosely coupled fusion between the global positioning system (GPS) and the inertial measurement unit (IMU). However, low-cost GPS receivers provide the position and velocity of the vehicle at a lower sampling rate than the IMU-sampled vehicle dynamics. In addition, the GPS measurements might be missed or delayed due to the receiver's inability to lock on the signal or due to obstruction from neighboring vehicles or infrastructures. In this paper, an architecture based on an adaptive neuro-fuzzy inference system is proposed for fusing the GPS/IMU measurements. This integration incorporates the variable delay between the IMU and GPS signals as an additional input to the fusion system. In addition, once the GPS signal becomes available, the measurement is used as a correction reference value to provide an enhancement to the estimation accuracy. The performance of the proposed method is initially demonstrated using a GPS/IMU simulation environment. Subsequently, an experimental test is also conducted to validate the performance of the method.

An error model for sensor simulation GPS and differential GPS

Abstract: This paper describes a software package that models various Global Positioning System (GPS) and differential GPS receiver configurations. The model produces position errors in a locally-level coordinate system. The errors are statistically based on the errors associated with pseudorange measurements. An orbital model of the GPS satellites simulates the effects of satellite geometry on the position errors. The error model is used in the Real-Time Simulator at the NASA-Langley Research Center. >

Accuracy of high‐rate GPS for seismology

Abstract: We built a device for translating a GPS antenna on a positioning table to simulate the ground motions caused by an earthquake. The earthquake simulator is accurate to better than 0.1 mm in position, and provides the "ground truth" displacements for assessing the technique of high-rate GPS. We found that the root-mean-square error of the 1-Hz GPS position estimates over the 15-min duration of the simulated seismic event was 2.5 mm, with approximately 96% of the observations in error by less than 5 mm, and is independent of GPS antenna motion. The error spectrum of the GPS estimates is approximately flicker noise, with a 50% decorrelation time for the position error of approx.1.6 s. We that, for the particular event simulated, the spectrum of dependent error in the GPS measurements. surface deformations exceeds the GPS error spectrum within a finite band. More studies are required to determine whether a generally optimal bandwidth exists for a target group of seismic events.