Analysis And Design On Modular Space Axial/Radial Telescopic Tire Building Drum Guiding Mechanism

This dissertation deals with the theory and methodology for the design of a newtype spatial axial/radial telescopic tire building drum guiding mechanism, includingtype synthesis, freedom analysis, kinematics modeling, rigid body dynamicsformulation. On the basis, proposed a dimensional synthesis optimization algorithmsand design flows by a successful design case. The following contributions have beenmade.On the basis of the system summarizes of the topology structural as well as itskinematic characteristics of tire building drum guiding mechanism, based on the ideaof modular design and using the Regenerated Motion Chain method, type synthesis ofthe tire building drum guiding mechanism is studied systematically, many newconfigurations for the tire building drum guiding mechanism are obtained. And amechanism is preferred according to the design requirements of the tire building drumguiding mechanism unit.Mobility analysis of the guiding mechanism is carried out using the mobilitymethodology based on reciprocal screw theory. The mechanism is decomposed intoseveral planar six linkage and three bar four kinematic pair branch chains. Judging thepartial freedom, virtual constraint and common constraint of all the kinematic chainsbased on screw theory and analyzed their degree of freedom respectively. Accordingto the principle of substitution of the generalized kinematic pair, mobility of thecomplex loop mechanism composed by multiple sub-chain was studied. By structuraldecomposition of the tire building drum mechanism, the number and property ofmobility for the mechanism was obtained.According to the kinematic characteristics of the forming drum guidingmechanism, the detailed and complete kinematics models between the driving jointsand specified output components are established, including the forward and inverseequations about position, velocity and acceleration. The explicit expression of the Jacobian matrix and the Hessian matrix are formulated, which are useful fordynamics modeling.Based on the kinematics models, the rigid body dynamic model of the guidingmechanism is formulated using the virtual work principle, which provide a theoreticalfoundation for actuator select, dynamic design and realization of the torque control inengineering prototype design stage.An optimal design method is proposed, whose objective function are composedby transmission quality indicators of inner tile driving mechanism and the outwardtile’s, used to evaluate the force transmission performance of guiding mechanism, theconstraint conditions are established based on the motion characteristics of themechanism. This optimal design method is studied with specific examples, and thecorrectness and effectiveness of the optimization algorithm are verified by thesimulation results.