· Running type · Appearance features: The top of the main unit is equipped with an additional running car (sports car), and the wheels of the car are stuck on the track. · Functional features: Mobile operation. The host machine is hung on a trolley that can walk along the track. It can not only lift it, but also pull the trolley to move left and right with the goods. · Applicable scenarios: Suitable for places where unloading needs to be moved along fixed lines (such as single-beam cranes and cantilever cranes), with wide coverage. · Cost and installation: The structure is complex and the cost is relatively high, but it saves the trouble of repeatedly moving the equipment during use.