Determining the parameters of the trajectory of the bucket of mining quarries excavators

Abstract

The bucket positioning of the excavator in three-dimensions (3-D) is the precondition of the robotic excavator starting automatized works. The electric excavator is one of the most widely used machinery in the mining industry, mainly due to its versatility and portability. Among the tasks performed by the excavator, there is a significant number of repetitive movements associated with moving the bucket to the unloading point and back to the face. Using automated functions to perform such repetitive tasks will not only significantly increase overall productivity, but also reduce energy consumption. This research is carried out to create a method of coordinate control of electric drives of the boom, dipper stick, and bucket of an electric excavator to perform accurate and efficient work. On the basis of the kinematic analysis of the excavator’s attachment system, the trajectory of the end of the working body can be determined from the point of view of the coordinated movement of the electric drives of the main mechanisms of the excavator. Thus, the complex algorithm of the excavator bucket 3-D position control can be carried out by coordinated control of the movement of three separate electric drives. This coordinate control algorithm was tested on the example of the EKG-8I excavator, and the results of the verification showed that this developed control method can satisfactorily perform the function of automatic control of the bucket position in three-dimensional space. Optimization of control will be further carried out based on the analysis of the energy efficiency of various possible trajectories.

Mathematical model of the closed-loop system of excavator bucket positioning

“…Work [4] is devoted to the kinematic analysis of the mechanical part of the excavator according to the "backhoe" scheme for closed-loop position control systems. In [5], the features of the interconnected operation of the mechanical part of the main mechanisms of the excavator according to the "front shovel" scheme are considered.…”

“…Currently, two electric drive systems are the most common for the main mechanisms of an excavator: an electric drive according to the "generator-motor" system (Ward Leonard System), and the "thyristor converter-motor" (TC-DC) electric drive succeeding it. Despite the popularity and simplicity of mathematical modeling of a DC machine, the development of a model of a complete electromechanical system of an excavator is not an easy task, which is due to the complex composition of electromechanical equipment, the widespread use of multi-motor electric drives, and the presence of complex relationships between individual mechanisms in the mechanical part of the excavator [5].…”