A Robust RTK Navigation and Positioning Method for a Quadruped Robot in Complex Dynamic Environments

Wei Zhang; Ziwen Qu; Xusheng Yang; Minglei Fu; Wen-An Zhang; Yuke Ji; Haoning Zhang; Boris Sokolov; Vladislav Alekseevich Sobolevskii; Valerii Zakharov

Wei Zhang zhejiang university of technology
Ziwen Qu zhejiang university of technology
Xusheng Yang zhejiang university of technology
Minglei Fu zhejiang university of technology
Wen-An Zhang zhejiang university of technology
Yuke Ji zhejiang university of technology
Haoning Zhang zhejiang university of technology
Boris Sokolov St. Petersburg Federal Research Center of the Russian Academy of Sciences
Vladislav Alekseevich Sobolevskii St. Petersburg Federal Research Center of the Russian Academy of Sciences
Valerii Zakharov St. Petersburg Federal Research Center of the Russian Academy of Sciences

Keywords: quadruped robot navigation, RTK, progressive Gaussian filtering, wide-lane guidance, dynamic positioning.

Abstract

A quadruped robot requires continuous, stable, and high-precision positioning for autonomous navigation in complex dynamic environments. However, its onboard GNSS observations are easily affected by tree canopy blockage, near-ground multipath, and endogenous electromagnetic interference from the platform. As a result, traditional dual-frequency RTK methods often suffer from long float periods, unstable ambiguity fixing, and poor trajectory continuity in complex scenes. To address this problem, this paper proposes a robust RTK positioning method that integrates wide-lane guidance constraints with a progressive Gaussian filtering update mechanism. The proposed approach follows a procedure of wide-lane guidance, progressive float estimation, and narrow-lane stepwise fixing. Based on dynamic experimental data collected from a quadruped robot in a campus environment, this paper compares the proposed AGF-WLL1 method with the conventional EKF-L1L2 method. The results show that the proposed method reduces the horizontal and vertical errors from 0.221 m and 0.319 m to 0.128 m and 0.178 m, respectively. The narrow-lane fixed-solution ratio increases from 67.054% to 77.286%, and the float-solution ratio decreases to 16.836%. The experimental results demonstrate that the proposed method enhances fixed-solution stability, trajectory continuity, and positioning robustness for quadruped robot navigation in environments with blockage and interference.