Fundamental Study on Estimation of Internal Condition in Piled Fragment Rocks by Use of Resistive Forces Acting on the Bucket of Wheel Loaders

摘要

In order to automate the scooping task, it is desired that the resistive forces acting on the bucket are obtained in advance prior to the scooping task. Therefore, some models to predict the resistive forces acting on the bucket were proposed already. But, many parameters such as the friction coefficient between the bucket and the rocks, the angle of internal friction, slope of the rock pile and rock density are necessary to calculate the resistive force from these models. However, these parameters are generally unknown before the task. Therefore, the machine needs to obtain these parameters autonomously.The purpose of this study is to obtain the friction coefficient between the bucket and the rocks, the angle of internal friction and particle diameters by using the resistive forces which are measured at the beginning of the task.In this study, the resistive forces were measured and the empirical equations to estimate the friction coefficient between the bucket and the rocks, the angle of internal friction and particle diameters were obtained. Furthermore, the method to judge the existence of huge rock in the pile was proposed by use of these equations.