Abstract: Two mathematical expressions of the derivatives of locus curve relative to its slope and curvature are presented，and based on the geometric constraints and dimension driven technique，a primary simulation mechanism for generating the path or function at several prescribed positions is developed．In the light of some basic tasks of higher-order approximate synthesis，two simulation mechanisms for higher-order and combined point-order synthesis are created respectively，and some key dimensions of the mechanism are modified and the influence of their variation on the simulation results are checked．All prescribed values are satisfied，and some desired configurations of the simulation mechanism are obtained．The results of approximate synthesis show that the simulation process is not only fairly quick and straightforward，but also accurate and repeatable．