Moving target localization method using foot mounted acceleration sensor for autonomous following robot

摘要

The development of an autonomous mobile robot system has expanded its application across various fields such as for medical service support, automatic vehicle operation, and delivery businesses. In recent years, we have developed a mobile robot which is tasked to follow a medical doctor from an arbitrary starting point to a patient's room, manage medical resources and a patient's electronic information in a hospital. The robot follows with its position being just a few meters behind the moving target person or the medical doctor. Here, when there is a blocking object between the target being followed and the observation sensor, the robot stops because it loses the target's position. Obstacles for these robots can be passers-by in straight corridors and corner walls encountered during turns. In this research, we propose a moving target localization method that directly measures or indirectly estimates the position of the robot's following target. A wearable acceleration sensor is attached to one-leg of the following target person and self-localization with high accuracy can be estimated by our proposed calculation algorithm based on inertial navigation information. As a compensation for positioning errors accumulated over time, the estimation calculation is processed according to correction information of the stance phase judgment by an acceleration sensor and the target's moving direction by LRF during walking in a straight line. Construction of the estimation compensation algorithm, its implementation on the mobile robot and a trial experiment of the robot following a specified person are described in detail.