Hydraulic excavator is a kind of engineering machinery with Multi-executive mechanism, which is mainly composed of three parts: walking chassis, rotary platform and working device. Each actuator can act independently, and multiple actuators can perform composite action together. In practice, it is mostly a compound action. In the process of operation, hydraulic excavator usually carries out periodic excavator action, and it can not walk in the excavation process, so its operation process is periodic.
A standard excavator operation cycle can be divided into four stages: excavation, full load lifting and turning, unloading and no-load return. The stage in which the swing system participates is full lift swing and no-load return. Full load lifting and rotating condition refers to the boom lifting and full load lifting by the boom hydraulic cylinder of hydraulic excavator after the excavation. The return condition of empty bucket mainly refers to the reverse rotation of the turntable to the new excavation position after the excavator unload the materials in the bucket. Meanwhile, the boom hydraulic cylinder and the stick hydraulic cylinder cooperate to lower the bucket to the excavation point.
