All robots avoid the rock area. After Excavator 1 goes to the rock area for excavation, Excavator 1 returns to the starting point, and all robots can pass through the rock area. After Dump Truck 1 and Excavator 2 go to the puddle area for excavation and unloading, Dump Truck 1 returns to the origin and unloads, and Excavator 2 also returns to the starting point.