Design and modeling of hardware-in-loop test bench for hydraulic excavator based on dynamic load emulation

Hardware-In-Loop (HIL) testing is an effective means to improve the development process of construction machinery. This paper presents a HIL test bench for hydraulic excavator based on dynamic load emulation. The critical technology of HIL test bench is the ability to emulate realistic load. Therefore, a digging load emulating model is established and implemented in real-time environment. To improve the load emulating accuracy, the soil-bucket interaction model is calibrated based on the coupling of the discrete element method (DEM) and multibody dynamics (MBD). The experimental scheme under positive and negative load working conditions is designed to correct the testing error. The performance of the HIL test bench is evaluated from multiple perspectives of load emulating accuracy, system power flow and fuel consumption. Compared with actual excavation tests, the testing error of the proposed HIL test bench is no more than 12%.