| Replenishment at sea is an important tactical and technical measures to improve the navy's combat capability.The Ship-mounted crane with good performance with the wave compensation is an important operating unit for ship at sea.Ship-mounted Crane is a combinational product of crane and industrial robot,it has the structural characteristics and the work methods of the robot and crane system at the same time,so work hard.Currently the gantry cranes have horizontal and vertical anti-sway device,but there is the poor adaptability for most of them,so it can not adapt to the reproduction of the goods,water salvage of goods and persons and the small life-saving boats under the bad sea conditions.The subject analyses the principle of the gantry cranes with the swing and variational amplitude,analyses the ship's posture of the bad sea conditions,establishes the model of the gantry crane with variational amplitude and the model of the ship's posture under the different sea conditions,and analyses the response of the crane to the different situations through the simulation.First of all,it analyses the principle of the marine crane,s structure,designs the hydraulic system scheme of the rack with variational amplitude,the hydraulic system scheme of lifting windlass and the scheme of the hydraulic system with the wave compensation,and analyses its working principle.It has established the hydraulic lifting system model of the crane with variational amplitude and analysed the model through the simulation.Then,it establishes the ship's moving model of the different sea conditions to analyse the movement of the ship,and analyses the effect of the device with the wave compensation to the performance of the crane under the different sea conditions.It has established the hydraulic lifting system model of the crane with varied amplitude and analyzed the model through the simulation.Through dynamics simulation,the influence of ship roll, pitch and heave motion due to ocean wave motion to performance of crane is known.When swing frequency is near ship pitch and roll frequency,and tensile force and swing amplitude of cargo increase,this affects the normal work,so the wave compensation system should be used to reduce swing amplitude.Then,it establishes the ship's moving model of the different sea conditions to analyze the movement of the ship,and analyses the effect of the device with the wave compensation to the performance of the crane under the different sea conditions. The dynamics model of no wave compensation is established,the cargo motion is simulated in different conditions,the influence of supply ship motion,different position of crane,arm angle of crane and Length of the sling are researched,the necessary basis of wave compensation system is give.Finally,it adopts PLC control technology to design the control system of the gantry cranes with variational amplitude,and practises the designation of the electric control system and the control program. |
