A portable robotic device (PRD) as well as related devices and methods are described herein. The PRD includes a 3-D imaging sensor configured to acquire corresponding intensity data frames and range data frames of the environment. An imaging processing module configured to identify a matched feature in the intensity data frames, obtain sets of 3-D coordinates representing the matched feature in the range data frames, and determine a pose change of the PRD based on the 3-D coordinates； and perform 3-D data segmentation of the range data frames to extract planar surfaces.
