This paper addresses two major issues in fixture layout design: 1) to determine the feasible fixture configurations that satisfy fundamental requirements suck as kinematic localization and total fixturing (form-closure); and 2) to evaluate the acceptable fixture designs on several quality criteria and select the optimal fixture appropriate with practical demands. The performance objectives considered include the workpiece localization accuracy, and the norm and distribution of the locator contact forces. An efficient automated tool based on an interchange algorithm is developed for designing optimal fixture layout for arbitrary 3D parts. A thorough analysis is performed on the fixture characteristics during the single and multicriteria optimization process for different frequent cases, and on the inter-relationship between locators and clamps, leading to conclusions and strategies for performing fixture synthesis.

This paper describes an approach to optimal design of a fixture layout with the minimum required number of elements, i.e., six locators and a clamp. The approach applies to parts with arbitrary 3D geometry and is restricted to be within a discrete domain of locations for placing the fixture elements of non-frictional contacts. The paper addresses two major issues: 1) to develop an efficient algorithm for fixture synthesis in the point set domain; and 2) to evaluate the acceptable fixture designs based on several performance criteria and to select the optimal fixture according to practical requirements. The performance objectives considered include the workpiece localization accuracy, and the norm and dispersion of the locator contact forces. An interchange algorithm with random initiation is developed. Also, the fixture performance characteristics are evaluated to understand their tradeoffs. The importance of the accurate localization and the contact force balance is discussed.

Addresses two issues in fixture layout design for 3D workpieces: (1) precision workpiece localization and (2) robust force-closure. An analysis is given to quantify these two fundamental requirements. Based on a concept of optimum experiment design, the optimal fixture design problems are treated to select optimal locators and clamps. An interchange algorithm is described, in which the fixture locators are generated sequentially first and are further improved. The algorithms use multiple criteria to balance the demands for precision localization and robust force closure. Examples are presented to illustrate the issues and to show the effectiveness of the proposed approach.