Dual Iterative Displacement Analysis of Spatial Mechanisms Using the CH Programming Language

Harry H. Cheng and Sean Thompson


A dual iterative method for displacement analysis of spatial mechanisms is presented in this paper. The algorithm and formulation based upon 3x3 dual transformation matrices are succinct. They can be implemented concisely in the CH programming language, a superset of C, which handles dual, dual double, and dual computational arrays polymorphically. The algorithm is numerically verified by dual iterative displacement analysis of spatial mechanisms. Comparison studies on stability, convergence, performance near singularities, and CPU time of the dual iterative method versus the real iterative method are conducted. It is shown that both dual and real iterative algorithms are stable with a comparable convergence rate even near singularities. But, the computational speed of the dual iterative formulation is about 2.18 times faster than that of the real iterative formulation when formulations are translated into CH programs for numerical calculation.

Integration Engineering Laboratory
Created by Harry H. Cheng, 12/15/1995