Investigation of performance of hydraulic excavators by co-simulation of multibody dynamics and discrete element method

Modelling of machine-material interaction system is challenging. Many efforts have been made in the past to predict machine-material interactions through analytical and numerical models. However, few studies have focused on the dynamic response of machine to materials in automated machine operations. In this work, the co-simulation of multibody dynamics for excavators and discrete element method for granular materials is employed to evaluate the excavator performance. The results show that the full working cycle of excavators can be well captured by the co-simulation method, and the variations of the hydraulic pressure and flow rate and the power consumption with cylinder positions can be obtained. The results also demonstrate that with the material density increasing, the bucket payload experiences small changes. The complex bucket-particle interactions mainly occur in the process of the digging, loading, and lifting, while the significant hydraulic power consumption and intense particle-to-bucket interactions take place in the digging process.