1. The structure and working principle of hydraulic transmission and components; 2. Demonstration control experiment of hydraulic excavator; 3. Electrical control experiment, electro-hydraulic integrated control experiment; 4. The structure and application of hydraulic valve block; 5. Demonstration control experiment of hydraulic excavator 6. The cross rocker controls the rotation operation, the boom is raised and the platform rotates at the same time 7. The cross rocker controls the unloading operation, and the bucket and stick work at the same time the boom can adjust the height of the position 8. The cross rocker controls the return, the platform rotates, the boom and the stick cooperate to return to the starting position of excavation