Automatic Estimation of the Position of a Rung in 3D Point Cloud for Ladder Climbing by Legged Robot

Abstract

In this paper, in the case where the three-dimensional coordinates of the end points of the cross-point of the vertical ladder, which is necessary for raising and lowering the disaster-responsive robot WAREC-1 attached to the vertical ladder, are unknown, the three-dimensional point cloud data acquired by LRF is analyzed, We proposed a method to estimate three-dimensional coordinates required for WAREC-1 to raise and lower a vertical ladder, and investigated. In the experiment, we investigated the installation position and angle of the sensor, and improved the estimation accuracy by optimizing the installation position and angle of the sensor. Experiments were conducted on vertical ladders composed of cylindrical / prismatic members, and the average values of the estimation errors were less than 7.1 mm and 9.1 mm, respectively. The proposed method can estimate the three dimensional coordinates of the cross-point required for the leg type robot WAREC-1 to raise and lower the vertical ladder.