We built a prototype measurement jig for installing 3D laser scanners at multiple points in pear orchard; further we developed methods for collecting point cloud data and “tree extraction, ” which enable to identify pear trees in the point cloud. The proposed tree extraction algorithm consists of four steps: Create grid; Remove points that lie on the ground surface; Remove points that lie on trellis wires using reflective intensity threshold; and Remove micro-noise via radius outlier removal. We measured 14 pear trees and successfully integrated 13,843,644 points into point cloud. The result obtained via tree extraction method demonstrate that the removal ratios for ground, wire, and micro-noise components were 100 %, 99.6 %, and 87.6 %, respectively, and the tree extraction accuracy was 94.5 %.
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