Synchronous Observer Design for Landmark-Inertial SLAM with Magnetometer and Intermittent GNSS Measurements
Authors: Arkadeep Saha, Pieter van Goor, Ravi Banavar
Organizations: Centre for Systems and Control, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India. · School of Aerospace, Mechanical and Mechatronic Engineering (AMME), Faculty of Engineering, University of Sydney, NSW, 2006, Australia.
In Landmark-Inertial Simultaneous Localisation and Mapping (LI-SLAM), the positions of landmarks in the environment and the robot's pose relative to these landmarks are estimated using landmark position measurements, and measurements from the Inertial Measurement Unit (IMU). However, the robot and landmark positions in the inertial frame, and the yaw of the robot, are not observable in LI-SLAM. This paper proposes a nonlinear observer for LI-SLAM that overcomes the observability constraints with the addition of intermittent GNSS position and magnetometer measurements. The full-state error dynamics of the proposed observer is shown to be both almost-globally asymptotically stable and locally exponentially stable, and this is validated using simulations.
Figures & tables
Fig. 1: The trajectories of the true and estimated robot and landmark positions over time. All the initial and final positions are marked with ∘ and ∗ respectively.
Fig. 2: The errors in attitude, velocity and the positions of the robot and landmarks over time. The green and red background shows whether GNSS is available or not.