A new mobile real-time localization system (RTLS) for a following robot application

Abstract

Localization is one of the main issues in wireless sensor networks (WSNs). In the conventional RTLS, three or more fixed anchor nodes at known positions are required. Prom the distances to the target node, the position of the target node is calculated by the trilateration or from the angles with the target nodes by triangulation. In this paper, the position of the moving target node can be calculated through the mobile anchor node configuration. The new mobile node scheme proposed in this paper attempts to overcome the limitation of knowing the location of individual mobile anchors. We have equipped three anchors on a single mobile robot platform in advance and, in order to chase the moving target, the position of the moving target node is calculated. Moreover, we conceptualize how the measured distance error affects the computed position error by deriving the analytical equation. Two factors affecting the position accuracy are the distances between the anchor nodes (anchor spacing) on the robot platform, and the distances between the anchor nodes on the robot and the target node. When the measured distance is compared with the simulation results, the position error remains within ranges of 4% to 10%. © 2020 Yokohama Publications. All rights reserved.