Theoretical And Experimental Research On Realizing Track For Controlled Five-bar Mechanism

The traditional mechanisms are taking place the deep change to such a great deal of respects as its research object, content, theory and method, etc. Since 1990, Chinese mechanisms go through a relatively develop on a large scale. Analysis, synthesize and its application of controlled mechanism is one main achievement of over the past 10 years among them.On the basis of drawing lessons from domestic and international relevant research results, type synthesis, analysis and synthesis, structural parameter and error distribution of movement parameter and its affection on realizing track, and control system of five-bar mechanism as the research object , considering kinematics and dynamics characteristics of five-bar mechanism, the new-type intellectual computing technology and new design theory are introduced , a kind of new research way has been offered for synthesis and innovation design of five-bar mechanism.Firstly, two new methods of type synthesis of five-bar mechanism are put forward, namely type synthesis method based on two similar Classâ…¡bar groups and two framed links + Classâ…¡bar groups. 13 basic types of the five-bar mechanism are deduced; then the evolutionary process and characteristic of the five-bar mechanism is proposed, which is based on .the selection of driving component and additive rod and so on. It offers theoretical basis for both the type and dimension synthesis of five-bar mechanism and the selection of its practical and reliable mechanism modes.Secondly, two new methods of two-step dimensional synthesis of five-bar mechanism accurately realizing the track of many points are built, namely two-step synthesis method of model of track realizing and compensation control, and model of track realizing and circle fitting. Basic conceptions of visual angle, in the track and outside the track are put forward, and then the optimal calculation models are reduced based on these conceptions. Global optimal design model, namely model of track realizing and compensation control, of controlled mechanism which accurately realizes the track of many points has been established. The number of individual design variable is six, which are less than the traditional method, but model is more. Fitness function build can satisfy that fitness value of satisfied individuals are better to the unsatisfied individuals and increase the optimal attraction zone. Global optimal solution is got by using genetic algorithm. Optimization models of track realizing model and circle fitting model of five-bar mechanism has been established. The generalized inverse method for solving compensation movement displacement has been presented. At last the instance indicates that mechanical features of controlled driving component and proper control strategy and methods are considered.Thirdly, proper distribution method of structural parameter error of five-bar mechanism is proposed.Low-frequence characteristic of compensation movement is enhanced by using wavelet transform and analysis method. In addition, the relation between error changes of controlled original power component and given track errors is also analyzed. It provides an important foundation for choosing controlled original power component. Numerical values of compensation movement are calculated by using basic methods of controlled mechanism, then wavelet transform and analysis method is put forward to analyze movement characteristic of compensation movement and its influence on realizing track. A feasible method is proposed to realize the random track and improve the characteristics of compensation movement only by changing compensation movement not changing structural parameters of five-bar mechanism.Finally, calculation simulation and control system software of five-bar mechanism is developed. Aiming at mechanical analysis of five-bar mechanism, mechanical model of five-bar mechanism is built by using matrix method. Then the all calculation, simulation model and software, control hardware system and its software are developed. All above offers design theories and application study of five-bar mechanism powerful support.