Dynamic Simulation And Experimental Analysis Of A Novel5-DoF Parallel Mechanism

To meet the demand for the high-efficient manufacturing of large structures inthe national aircraft and automotive industry, this thesis investigates into the finiteelement model of the T5robot---a novel5-degree-of-freedom parallel manipulator,research contents including the theoretical model of rolling bearing, finite elementmodel of T5robot and its experimental analysis etc. The following works have beenaccomplished.1. Stiffness Identification of Rolling Bearings. The mapping relationshipbetween the stiffness parameters and modal parameters are formulated by means ofthe transfer matrix method, and then its natural characteristics and stiffnessparameters are obtained by means of the experimental method before modifying thefinite element model of rolling bearings.2. Finite Element Model. On the basis of SAMCEF Dynam software, the T5robot can be disassembled several sub-structures, and then the finite element model ofthe robot can be formulated by means of the pose frames of sub-structures. Bychanging the pose frames, the finite element models are established easily at differentconfigurations.3. Experimental Analysis. An experimental modal analysis (EMA) is carried outto the physical prototype of T5robot. The mode shapes of interest from the simulationagree well with the ones from the test, and the error of nature frequencies gets lessthan10%.4. Sensitivity Analysis. The static stiffness joints influence the nature frequenciesof all mode shapes, but differently and limited---according to the sensitivity analysisperformed in this thesis based on the finite element model.The results show that the proposed finite element modeling method is efficient todeal with the flexible links, joints and interface. The proposed simulation model is effective to predict the system natural frequencies, mode shapes, and is able toreanalysis against the changing of configurations of the parallel mechanism.