Voxel-Based Localization and Mapping for Multirobot System in GPS-Denied Environments

Collaboration localization and mapping in GPS-denied environments is a challenging problem, due to the computing power and communication bandwidth constraints of onboard equipment. In this article, a voxel-based localization and mapping system is developed, which achieves real-time trajectory estimation for the multirobot system utilizing only onboard sensors, computing power, and communication module. The key idea of the voxel-based matching approach is to formulate the registration problem as a maximum a posteriori (MAP) problem and to simplify it to a nonlinear least-squares problem using Gauss approximation and principal component analysis (PCA). The voxel-based matching method significantly improves the computational efficiency and reduces the communication bandwidth of the localization and mapping system. The effectiveness of the proposed method is demonstrated through experiments in real-world environments for various scenarios.