Modeling of Part-Fixture Dynamics With Application to Synthesis of Dedicated and Flexible Fixturing Systems

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

This grant provides funding for the development of models for analysis of part-fixture dynamics in machining and application of these models to the synthesis of dedicated and flexible fixturing systems. The models developed in this research will enable part-fixture interaction to be considered in the stability analysis of multiple-point machining processes such as milling. In addition, the models will allow the impact of part-fixture dynamics on the final part quality to be analyzed and accounted for in the synthesis of both dedicated and flexible fixturing systems. To achieve this goal, a dynamic model of the part-fixture system accounting for the effects of micro-slip induced damping will be developed. A simplified lumped parameter approach based on contact elasticity principles will be used to develop the model. The model will account for nonlinearities arising from unilateral contact conditions, micro-slip and gross stick-slip. In addition, a modified dynamic friction tester will be used to develop empirical models of part-fixture contact friction for use with the dynamic model. The dynamic part-fixture model will be applied to the analysis and synthesis of both dedicated and flexible machining fixtures such as the pin-array flexible fixture. On a fundamental level, the models developed in this research will complement the existing body of scientific knowledge in part fixturing. On a practical level, it will provide the necessary dynamic analysis and synthesis tools, heretofore unavailable, for designers and end-users of dedicated and flexible fixturing systems. Application of these models will lead to the development and implementation of truly process-capable fixtures.