Abstract
Operations of hydraulic excavators require high operation skill and operators have possibilities to work in unsafe environment. To solve these problems, automatic digging control is often studied, but there are few studies focused on improvement of efficiency. A high efficiency digging algorithm for a hydraulic excavator has not been established because the relationship between digging parameters and digging performance is complex. A simulation model which is able to consider interaction between soil and machine would uncover a digging algorithm for improving energetic efficiency. In this paper, an example for improvement of digging efficiency is shown by our developed distinct element method (DEM) simulation. First, validity of digging performance evaluation with developed simulation is shown by developed digging test device. The device reproduces excavation by driving soil packed container with three motors and by rotating bucket with a motor. And it can measure digging resistance by force sensors and calculate digging energy. Digging simulations are conducted by our suggested automatic digging algorithm. Varying control parameters, influences of control parameters are estimated. Our research evaluates effectiveness of model-based development for automatic digging which enhances productivity.
