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Research on Optimal Excavating Trajectory of Large Mining Shovel

Excavating trajectory impact the production efficiency and overall performance of excavator directly [1]. Hence, it’s of very realistic significance to obtain the optimal excavating trajectory. Based on site test data, the point of tangency of the rack pitch line of the bucket rod and the pitch circle of the crowd gear were determined as the rotating center and the dynamic model of working mechanism was derived; due to the change law of the current and voltage of the hoist motor, the excavating process sections was separated from the excavating trajectory; log spiral model was chosen as the fitting function, and according to the following three judgment rules: maximizing soil volume in bucket, rationalizing the excavating time and minimizing the energy consumption of unit mass of soil in bucket, the optimal excavating trajectory was obtained and provided basis for the operation and design of the large mining excavator [2].