The theory and methodology for concurrent design and planning of reconfiguration fixture

Abstract

A methodology for concurrent design and planning of adaptable fixture configuration and computer aided design of fixturing systems is presented. Emphasis is put on the analytical considerations involved in the optimization for the design of the locators, clamps, and supports. The accessibility/detachability condition, determination condition, and force-assemblability condition of positioning by a set of locators are derived for workpieces with smooth analytical surfaces and for prismatic components. The relative form closure is defined on the basis of geometrical reasoning, and is achieved in terms of locators and clamps. Difference performance indices are proposed in order to select the optimum placement for the locators, clamps and supports. An approach to examining the relative form closure conditions for fixturing systems is adopted based on the J-junction concept, and the corresponding procedure for computer aided planning systems including analysis and synthesis functions of fixturing systems is developed. Details of the definition and properties of the J-functions are given, together with their applications to geometrical reasoning using simplified examples of fixturing system design and configurations planning. >