| Integrated hydraulic system (IHS) offers many advantages including reduced connectors, size and complexity, and enhanced flexibility for installation and maintenance. It provides a cleaner, leak-free, less vibrant and more reliable solution to difficult machine control system problems. So it is widely used in such fields as mechanism, metallurgy, forging, aviation, space flight, shipping and soon.As the key component of IHS, hydraulic manifold block (HMB) is still difficult to be designed in nowadays factories. One reason for that is the complexity of this problem, which mainly consists of outer layout and inner connection problems. The other reason is the most difficult works of combined layout and connection problems are still unsolved by current CAD technology. Combining modern intelligent optimization algorithms with engineering application, approaches that can automatically attain the optimum integrated layout and connection schemes restricted by some performances are researched in this paper in order to solve the above problems.After summarizing research findings at home and abroad, it is definitely raised that the core of HMB design is the problem of automatic optimization of outer spatial layout scheme under propped by automatic inner connection algorithm of channels. It can be boiled down to combinatorial optimization problem in mathematics.On the basis of summarizing the complexity and structural features of HMB and rules of its design and manufacture and analyzing the spatial relationship in 3D layout of HMB, the expressions of relevant variants are put forward using the Object-Oriented approach. Then the optimization objects and constraints are defined, thus the optimization model of HMB design is represented. This is a complex multi-objective, multi-constraint, multi-modal engineering problem. After analyzing how to deal with the multi-objective optimization and constraints, the technological strategies of optimal design of HMB are given.Based on the unified framework of generalized neighbor search algorithms, NCSA algorithm that is composed of Genetic Algorithm and Simulated Annealing algorithm on the basis of niche technology is brought forward. Meanwhile, its characteristics, convergence, and efficiency are also discussed. A typical multi-modal function is used to verify this algorithm's experimental features. The research shows that NGSA has higher ability for global and local search; it can find all optimum values efficiently; it is not very rigorous with the selection of control parameters. So it is a multi-modal optimization algorithm with higher capability, efficiency, and reliability. This algorithm will be used to solve the HMB design problem.The HMB design is divided into six procedures, which are channel check, lineweb connection, network connection, shape interference check, volume Reduction and layout design. The mathematical model and application algorithm of each procedure are given. The results of calculation show that these algorithms are succinct, efficient, accurate, reliable, and they can accomplish the optimal design of integrated layout and connection scheme with high intelligence.Adopting the sectionalized lumped parameter method with dynamic friction, the dynamic performances of the typical segments in lineweb, i.e. short channels, rectangular elbows, forked channel, chamber of additional holes, are analyzed using the effective approach-Power Bond Graph (PBG). Thus the PBG model of lineweb with the sectionalized lumped parameter method i:;IIIestablished. This model is proven by digital simulation and physical experiment. After summarizing those rules, the automatic modeling approach that can derive PBG model and parameters' value of lineweb from its geometric structure is presented. By this approach, HMB design can not only implement structural optimization but also meet the dynamic performance constraints.Based on the researches mentioned above, a HMB optimal design software package with high intelligence is developed successfully using Visual...
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