| The problem of configuration design and synthesis on the parallel mechanism with the five-bar closed-chain is researched in this paper. The forward kinematics problem, the workplace problem, the accuracy design and accuracy compensation problem, the motion simulation of the solid model and the mechanism bar's interference analysis problem on the 6-DOF hybrid driven parallel mechanism with the five-bar closed-chain have been thorough studied.The problem of configuration synthesis on the parallel mechanism with the five-bar closed-chain has been researched in this paper. By researching the type, kinematics performance, topological characteristics of plane five-bar close-chain structure, the Grey-fuzzy judgment method of the mechanism design scheme is proposed to solve the problem of the mechanism innovation design , and some practical examples are given to analyze and verify this method. The application of 5R and RPRPR close-chain structure to plane parallel mechanisms and spatial parallel mechanisms is studied mostly. A new method and procedure of the configuration synthesis for the parallel mechanism with the five-bar closed-chain is given, The four kinds of 4-DOF. the two kinds of 5-DOF, and the two kinds of 6-DOF spatial parallel mechanism are presented by this method.The forward kinematics problem of 6-DOF hybrid driven parallel mechanism with the five-bar closed-chain is researched. The kinematics mathematical model is built by using the method of combining the geometrical analysis with virtual bar's length based on the geometrical structure characteristics of 6-DOF hybrid driven parallel mechanism, and the solving of the forward kinematics problem of parallel mechanism is considered as the solving the extremum problems of the systems of nonlinear multivariable equations provided with the strong coupling feature, so the improved genetic algorithm is presented to optimize and solve directly the whole real solutions of the forward kinematics of parallel mechanism, and furthermore, a new method for grouping the solved solutions is presented by calculating the grey correlative degree, which is proved to be easy and high accuracy by the analysis result of some practical examples. This method is completely useful to solve the forward kinematics of parallel mechanism composed of the different structural forms, so a new method is provided to solve the forward kinematics problem of parallel mechanism.By considering the symmetry structure characteristics of this 6-DOF parallel mechanism and combining the workspace of the planar five-bar mechanism, the forming process of the whole workspace is analyzed by using the pole space method. On the basis of analyzing the workspace constraints of parallel mechanism, based on the inverse kinematics equation and through boundary extremum search method, the 3D chart of parallel platform mechanism workspace and the workspacesection shape in the X-Y planes corresponding to the different Z value are given. By adopting the effective cylinder volume to measure the workspace and detailed analyzing the influence that the platform structure size brings to the workspace shape, the influence curve which the each parameter brings to the effective cylinder volume is given. Based on the Kinematic equation and its inverse/forward solution, the singularity of the mechanism are analyzed by Jacobian matrix.The problem of the accuracy design and accuracy compensation of parallel platform mechanism is studied. By considering the influence of the random of clearance error caused by the spherical hinges and rotational hinges, on the basis of the inverse kinematics, the practical error model of this new type 6-DOF parallel platform is established and The Monte Carlo simulation analysis and the sensitivity analysis on the error have been done. The influence which the variation of structural parameters of the platform brings to the error has been done by the computer simulation analysis. This paper puts forward this method that the accuracy synthesis problem will be translated into the nonlinear optimization problems of a multi-objective and multi-variable and the solution is solved by the chaos genetic algorithm. Further more, a new method and procedure that establishes the optimized mathematic model on the accuracy synthesis is given. Aiming at the problem of the accuracy compensation of 6-DOF spatial parallel mechanism, a method progressed by the error direct compensation is proposed and the simulation calculation of some practical examples is given.The solid model of 6-DOF hybrid driven parallel mechanism with the five-bar closed-chain is built by using the Pro/ENGINEER software. The interference problem on the parallel mechanism is visually analyzed and studied by adopting the visual kinematics simulation, which builds the foundation for the other performance analysis and the optimization of the whole machine.
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