The Research And Development On Auto Crane Electro-hydraulic Proportional Control System

Electro-hydraulic proportional control technology is critic to construction mechanism including auto crane. With rapid development of Chinese fundamental constructions, more and more auto cranes are needed. It provide a good opportunity of expanding this market and making fortune for both abroad and civil auto crane manufacturer. But there are some difficulties to compete with overseas counterparts for civil manufacturer. One reason is that poor of technical level, most civil manufacturers'products are based on the imported electro-hydraulic proportional controller which is act as the core, as a result, the cost become higher and lost the advantage of lower cost. The other lies in the imported electro-hydraulic controller itself. Being a general product, the imported control doesn't work well in particular working conditions in China. Based on above two points, developing electro-hydraulic proportional controller of having independent intellectual property is now urgent to civil auto crane manufacturer.At the beginning, in this thesis, a serial of models about auto crane's function, construction and action are provided after being carefully analyzed with the modeling tool UML (United Modeling Language). Using these models, we can easily get along with the design and realization of electro-hydraulic proportional controller. Then in the second part of the thesis, system design pattern is discussed. According actual situations, a system design pattern called"Double CPU Share Memory"is adopted for such a kind of electro-hydraulic proportional controller. So in the third part, the concrete realization is presented to show the efficiency of the system design pattern, in the middle of which it emphatically give out the design of the hardware driving model. At the last part, for the proportional amplifier-electromagnet system, a PI controller is designed and by testing it is proved to be effective.The results of experiments have show that electro-hydraulic proportional control system and its core controller of the auto crane's performance are satisfied. It has the advantage of easily using and low cost, then it is worthy of further developing.