Dimensional Synthesis Of Planar Linkage Mechanisms Based On Numerical Atlases And Expert System

The dimensional synthesis of planar linkage mechanisms is the main content of linkage mechanism design. Through the efforts of mechanism scholars, A large number of dimensional synthesis methods are presented. But the existing dimensional synthesis methods all have various kinds of limitations. Each of them is only suitable for one or a kind of linkages synthesis. So two aspects as follows are mainly studied in this dissertation.Firstly, Numerical atlases method based on harmonic theory and Fast Fourier Transform (FFT) is investigated and further perfect. Rigid-body guidance synthesis, function generation synthesis, path synthesis of planar four-bar linkage mechanism for any given points or position are solved with numerical atlases method. Slider-crank mechanism for rigid-body guidance and five-bar linkage mechanism for path generation with random position are also synthesized using this method. A set of unified method system of planar linkage mechanism dimensional synthesis is formed.Secondly, the expert system for dimensional synthesis of planar linkage mechanism (ESDSPLM) which integrating many present outstanding synthesis methods is set up. It is developed through synthesis-analysis and. design-simulation method, and database programming technology, object-oriented technology and expert system construction technology are adopted. With the tool of Visual C++6.0, the ESDSPLM is achieved. This expert system is intellectualized, available and it has a friendly interface.A lot of jobs have been carried out rounding these two main respects. Numerical atlases method is further improved by using unified FFT arithmetic. The dimensional synthesis of planar linkage mechanism is studied by using numerical atlases method, and the formulae of determining the real dimensions of the linkages are given. On the base of relevant references, The Design Method Base including many present synthesis methods is set up through programming. Three standard numerical atlases database for dimensional synthesis of four-bar linkage mechanism, and the dimensional synthesis of four-bar linkage mechanism is solved completely. Two numerical atlases database of slider-crank mechanism for rigid-body guidance and function generation synthesis is set up. At the same time, several standard numerical atlases databases used in five-bar linkage mechanism dimensional synthesis are finished. Automated extraction of characteristicparameters and automated establishment of standard numerical atlas base are realized by using VC++ database programming. By using of the dialog box nesting technology, the design wizard is created, which can guide user to complete the data input step by step. Many kinds of data input way are set up for users to choose. Many kinematics analysis programme of planar linkage mechanism is accomplished. At last the kinematics simulation and performance analysis of the result are displayed in the ESDSPLM mainframe.Finally usage method of ESDSPLM is introduced, and a lot of examples are given to illustrate the efficiency and advantage of ESDSPLM.