Hybrid Transverse Polar Navigation for High-Precision and Long-Term INSs

Abstract

Transverse navigation has been proposed to help inertial navigation systems (INSs) fill the gap of polar navigation ability. However, as the transverse system does not have the ability of navigate globally, a complicated switch between the transverse and the traditional algorithms is necessary when the system moves across the polar circles. To maintain the inner continuity and consistency of the core algorithm, a hybrid transverse polar navigation is proposed in this research based on a combination of Earth-fixed-frame mechanization and transverse-frame outputs. Furthermore, a thorough analysis of kinematic error characteristics, proper damping technology and corresponding long-term contributions of main error sources is conducted for the high-precision INSs. According to the analytical expressions of the long-term navigation errors in polar areas, the 24-h period symmetrical oscillation with a slowly divergent amplitude dominates the transverse horizontal position errors, and the first-order drift dominates the transverse azimuth error, which results from the g0 gyro drift coefficients that occur in corresponding directions. Simulations are conducted to validate the theoretical analysis and the deduced analytical expressions. The results show that the proposed hybrid transverse navigation can ensure the same accuracy and oscillation characteristics in polar areas as the traditional algorithm in low and mid latitude regions.

A Vision Aided Initial Alignment Method of Strapdown Inertial Navigation Systems in Polar Regions

“…The inertial navigation system (INS) has high autonomy and is not affected by external factors such as climate and positions, so it can continuously provide speed and attitude information. Therefore, as one of the main components of the AUV navigation system, the inertial navigation system has become the key for AUV to complete its polar resource exploration mission [7].…”

Polar Region Integrated Navigation Method Based on Covariance Transformation

“…Essentially, the virtual sphere n-vector algorithm is the same as the e-frame algorithm and its azimuth definition is indistinct. The researchers of [11] and [16] proposed a hybrid polar navigation method, which accomplishes the inertial navigation mechanization in the e-frame, whereas it outputs the navigation parameters in the G-frame or t-frame. In addition, the studies of [11,16] introduce a position matrix to decouple the height channel and three rectangular coordinates, which can solve the problem of position error divergence.…”