Research On The Electro-hydraulic Control System Of Deck Lift Platform Based On Telescopic Cylinders

Deck lifting platform is a mobile equipment used for deck lifting operation in roll-on/roll-off ship. It is impossible to select single stage cylinder synchronous control mode with position guide machinery because the deck lifter need to climb and walk between two close decks and the stroke of lifting the deck is long. So that synchronization control mode must be taken in which telescopic cylinders are the actuators. But application and development of telescopic cylinder electro-hydraulic synchronous control system is limited because of the existence of the weak stiffness characteristics, sudden change of effect area and structural coupling in systems. Therefore, there is a very important significance to analyze internal control features of telescopic cylinder electro-hydraulic control system deeply and improve the synchronization performance of the system.The subject does some research on the influence of the various control components from electro-hydraulic control system on the telescopic cylinder displacement, including the model of valve controlling cylinder, dividing valve model and telescopic cylinder model, based on which the results of theoretical analysis was validated preliminarily by the use of simulation software. Then deck lifting platform was built to make field experiment for the purpose of validating rationality and reliability of system design, which provides a reference for the design of such telescopic cylinder synchronization system.In chapter one, the present situation of telescopic cylinder synchronous control system was introduced and research background, significance and main research contents of the subject was elaborated.In chapter two, work requirements and objective capability of the deck lift were presented, based on which various systems of the lift was build. And then various components of the lift were introduced and operating principle of these various components were analyzed.In chapter three, mathematical models of hydraulic control system of the deck lift was established including the valve controlling cylinder model, the dividing valve model and the telescopic cylinder model, based on which to analyze the effects of the various components on the telescopic hydraulic cylinder displacement.In chapter four, simulation analysis was executed for the single cylinder, double cylinders and four cylinders model to obtain corresponding simulation results using AMESim and ADAMS software.In chapter five, platform up-down control experiments were carried out under the different load and different control mode were compared via experiments. Then the phenomenon and harm of crawling was described and the corresponding measures was raised to resolve.In chapter six, the work done by the subject and the lack of research were summarized and future studies for the telescopic cylinder platform lift electro-hydraulic control system were prospected.