Method and system for localizing a mobile robot

A method of localizing a mobile robot with respect to a target object using an initial map of a reference object which is a representation of the target object, the mobile robot comprising a pose data update module, a motion controller, a LiDAR device and a localization controller communicatively coupled to the pose data update module, the motion controller and the LiDAR device, the method comprising

• (i) obtaining LiDAR data, by the localization controller, of the target object captured by the LiDAR device of the mobile robot as the mobile robot traverses in an environment associated with the target object, the LiDAR data including respective point cloud representations of the target object and the environment in various sampling instances;
• (ii) as the mobile robot traverses the environment, iteratively updating, by the pose data update module, pose data representing an estimated pose of the mobile robot with respect to a known reference location of the target object in corresponding sampling instances;
• (iii) extracting, by the localization controller, a subset of LiDAR data points in the point cloud representation of a previous sampling instance, the subset of LiDAR data points corresponding only to features of the target object in the initial map based on the estimated pose of the mobile robot associated with the previous sampling instance, the subset of LiDAR data points excluding information that corresponds to other objects in the environment;
• (iv) obtaining, by the localization controller, desired LiDAR data points in the point cloud representation in a current sampling instance, the desired LiDAR data points including current LiDAR data points which correspond to the extracted subset of LiDAR data points in the previous sampling instance, the desired LiDAR data points excluding information that corresponds to other objects in the environment;
• (v) filtering, by the localization controller, the desired LiDAR data points based on a probability of retaining each desired LiDAR data point to generate filtered desired LiDAR data points, the retaining probability being directly proportional to respective distances of the LiDAR device to the desired LiDAR data points, wherein the retaining probability equals 1 when the distance equals a maximum distance recorded in the point cloud representation in the current sampling instance whereby the desired LiDAR data points associated with a retaining probability of 1 are retained in the filtered desired LiDAR data points;
• (vi) determining, by the localization controller, a localization pose of the mobile robot with respect to the target object in the current sampling instance based on the filtered desired LiDAR data points;
• and
• (vii) controlling, by the localization controller, the motion controller to cause movement of the mobile robot in the environment based on the determined localization pose.