Development of Pruning Robot flexible for uneven surface of tree

在本研究中，我们的目标是开发一种修剪机器人，即使是逐渐弯曲或不均匀的树木修剪没有损坏，通过缩小切割机。由于可以修剪树枝的区域会减少，因此有必要通过移动小型切割机来积极修剪。1.移动的平台实验制作了四个能够上下树的移动的平台。2.测量系统开发了距离测量系统和直径测量系统作为树枝检测和位置识别系统。距离测量系统测量从根部设置的机器人与树枝之间的距离。直径测量系统测量机器人所设置的高度上的树木的直径。3.用于识别树枝位置的系统该系统使用来自测量系统的信息基于Occupational Grid模型来估计检测到的树枝的位置。我们揭示了像一棵树的表面上的测量特性，并提出了一个指定的分支检测模型。此外，我们还提出了一种压缩地图的方法和补偿传感器位置的方法，旨在用于实际森林环境。4.切割单元为了选择小型切割机，对一些切割机的切割特性进行了比较。并对小型切割机的修剪阻力进行了测量。5.切割机的运动规划我们将树枝分为位置可识别的树枝和由于被树枝遮挡而无法识别的树枝。提出了这几类树枝的运动规划算法，分别利用切割单元进行主动修剪。

In this research, we aim to develop a pruning robot capable of pruning even for gradually curving or uneven tree without damages by downsizing a cutting machine. Because an area in which branches can be cut will lessen, it becomes necessary to prune actively by moving the small cutting machine. For this purpose, following developments are conducted.1.Mobile platformFour mobile platforms capable of going up/down tree spirally are made experimentally. As a result, stable climbing is carried out.2.Mesurement systemsA distance measurement system and a diameter measurement system are developed as systems for detecting branches and recognizing their positions. The distance measurement system measures distances between a robot set up from a root and branches. The diameter measurement system measures diameter ; of tree on height in which the robot set up.3.System for recognizing branches' positionThis system estimates positions of detected branches based on the Occupancy Grid model using information from the measurement systems. We revealed characteristics for measurements on a surface like a tree and proposed a model specified for a branch detection. Moreover we proposed a method for compressing a map and a method for compensating sensor positions intending use in actual forest environments.4.Cutting unitTo select small cutting mechines, a comparison of cutting characteristics between some ones is conducted. Moreover resistances on pruning of the small cutting mechines are measured. As a result, a roughing endmill is found as one by which stable pruning are carried out with the least power.5.Motion planning of cutting machineWe categorized branches into branches whose positions are recognized and branches which cannot be detected due to occlusion by former ones. Motion planning algorithms for these categories of branches are proposed to carry out active pruning using the cutting unit respectively.