狭隘環境における水中ロボットの位置推定手法

―人工構造物点検の自動化に向けて―

抄録

In this work, we propose a new localization method for underwater robots that can survey narrow environments. The proposed method is based on 3-D map matching, by referring to environmental maps generated from design data and structural shapes measured by an ultrasonic sensor. This paper describes details of the method and calculation algorithms for using an ultrasonic sensor as a structural shape measurement sensor. Additionally, we present experimental results to evaluate the performance. To realize the proposed method, the signals reflected by the structures that include multi-pass signals are used for the environmental information measurement using an ultrasonic sensor. For environmental map generation with multi-pass signals of an ultrasonic sensor, the 3-D trajectory of the ultrasonic wave is calculated by applying the ray tracing method, an approximate calculation method in which the ultrasonic beam is approximated by bundle of acoustic rays. We confirm experimentally that the localization error was decreased in case of using an environmental map considered multi-pass signals of the ultrasonic sensor.