MODELING AND SIMULATION OF THE SWING SYSTEM OF CRAWLER-TYPE MEDIUM HYDRAULIC EXCAVATOR USING DYNAMIC FRICTION MODEL

摘要

An analysis model is presented in this paper to simulate the dynamics of the swing system of crawler-type medium hydraulic excavator. It is found from experiments that the static friction model cannot simulate actual friction phenomena such as the Stribeck effect which can be observed in real swing system. A dynamic friction model, i.e., the simplified LuGre model, has been implemented for more accurate simulation in the theoretical analysis. The validity of the simulation model adopting the dynamic friction model has been verified by comparing in time domain the simulated swing angle with that from actual swing test. Cross-correlation between the simulated and measured swing angles turned out to be 0.92. It can be concluded, therefore, that the proposed dynamic friction model considerably improves the simulation accuracy.