As the water flowing through a reservoir, the floating probably stays in somewhere. Sometimes the floating can be breathed into the mouth of power engine and may do harm to the engine. Most time it will populate the water. So the floating must be selected in time. This machine can be fixed on the bank, grab floating and move along with tracks to grab in larger area. It can work efficiency, grab the floating in some dangerous area ahead the dam. The design is combined the structure of arm crane and the caterpillar tread crane, and loads analysis is according to the worst condition. All calculation results passed the stability check.