Analysis And Design Of Two - Degree - Of - Freedom Translating Parallel Mechanism With Passive Hinge For Ball Hinge

The low degree of freedoms parallel mechanism, as an important component of the parallel mechanism, is paid more and more attention on in recent years because of the advantages of simple structure, fewer costs in controlling and manufacturing comparatively and high stiffness. Among which, the 2-DOF (degree of freedom) translational parallel mechanism Therefore, the 2-DOF translational parallel mechanism is a typical kind.Taking a novel 2-DOF translational parallel mechanism with passive spherical joints as the analysis object, this pager has analyzed the degree of freedom, the kinematics and the spatial static stiffness, and puts forward the practical applications of the mechanism.The closed form solution is developed for forward kinematics of position so that the degree of freedom is analyzed. Then the results are checked through the numerical example and kinematics simulations. According to the structural characteristics of this mechanism, there geometry constraints are proposed. Based on the there constraints, several kinds of extended structures are presented.In terms of kinematics, both inverse and forward kinematics model are established, and forward kinematics of position is analyzed through Jacobi matrix method. Based on which, the output velocity and acceleration are derived by taking derivation method. By an equivalent planar mechanism of the 2-DOF translational parallel mechanism, its singularities are analyzed.Based on the superposition principle at small strain and the virtual mechanism method, the spatial static stiffness model of two degrees translational parallel mechanism is obtained by using a quite comprehensive analytical approach of spatial static stiffness. And the principal stiffness and divection are analyzed. Using finite element software, the spatial static stiffness of the mechanism and its equivalent planar mechanism are compared, which verify that the mechanism has a higher lateral stiffness.Finally, practical application examples of the 2-DOF translational parallel mechanism are proposed.