Mechanism Synthesis And Characterization Of The Variable Topology Parallel Tire Building Drum Mechanism

The variable topology parallel mechanism is a series of parallel mechanisms, which have the similar topology but different mechanical characteristics. The in-depth research on synthesis method for the variable topology parallel mechanism can help not only to discover more configurations, but also provide a theoretical basis to select adaptive configurations, optimize configurations and computer-aided design. Based on the basic definition of variable parallel mechanism, the application for the tire building drum is discussed and the kinematics and dynamics performance before and after the topology of parallel mechanism changes are also analyzed.Firstly, the basic theory of variable parallel mechanism, combined with the mathematical definition and pertinence theory of the variable topology mechanism, which can further improve the theoretical system of the variable topology parallel mechanism. The topology changing way, topological description and topology and displacement output are studied through taking a typical parallel mechanism for an example.Secondly, based on Screw theory, combined with topology learning and group theory, the integrated process of variable topology parallel mechanism are analyzed, the topological analysis is given in several states of the folding process of the tire building drum. The variable topology parallel mechanism is applied to design the folding mechanism of the tire building drum; the configuration type of parallel mechanism is analyzed in detail, which can realize two sliding and one rotation movement. Using the screw theory synthesis method, it is given the integrated process of the variable topology parallel tire building drum mechanism, which can provide alternative structure type in the variable topology parallel tire building drum mechanism designed.Thirdly, the establishment of virtual prototype and analysis of Kinetic Characteristics. The accessory models and the virtual prototype are created in UG software, the output characteristic matrix,DOF,forward and inverse position solution and workspace are also analyzed.Then the kinematics analysis of the tire building drum is given and the kinematics characteristics of simulation analysis are analyzed by using ADAMS. Finally, according to the movement output of tire building drum mechanism, driver functions which add on the tire building drum mechanism are optimized, so that throughout the folding process the impact of tire building drum mechanism is improved noticeably.Finally, analysis of Dynamic Characteristics. Based on the analysis of the kinematic characteristics,the kinetic model of the variable topology parallel tire building drum mechanism are created using the method of the Newton-Euler dynamic equation, so that the study of the variable topology parallel tire building drum mechanism is more comprehensive. The simulation analysis and verification of dynamics characteristics of variable topology parallel tire building drum are analyzed in ADAMS software.Through the above analysis and studies, the theoretical system of the variable topology parallel mechanism is improved, and in-depth understanding of the topology parameters affecting to the performance of mechanism is discussed, which benefits for the creative design and application of the variable topology parallel mechanism.