Forward Kinematic Analysis on the Parallel Supporting Structure of Large Opto-electronic Equipments

摘要

According to the topologic system of parallel supporting structure, the geometrical constraints are obtained. And the forward kinematic model with analytical expressions can be established by eliminating the unknown terms. It is shown that the analytical solutions of the forward kinematic model have 16 groups. In order to decrease the number of solutions and get exact position-stance of the parallel structure, Newton-Raphson method is used to search the best numerical solutions by the judgement of terminal value. The corresponding numerical simulation proves that the exact forward solution can be found rapidly by iterative steps. Moreover, aiming at improving numerical precision, some measures on the choice of initial value and iterative step have been put forward. The forward kinematic model provides the basis of the perfect control of parallel supporting structure.