Design for Fixturability (DFF) Methodology for Commodity Parts: A Case Study With Connecting Rod Designs

Abstract

This paper presents a methodology called ÔDesign for FixturabilityÕ (DFF). This methodology enables designers to perform manufacturability analysis of their product designs upfront into the design process. The DFF approach provides a mapping between parametric representation of a part design and fixturing capability of a facility and presents a methodology to evaluate the design with respect to the fixturing capabilities. The methodology is applicable to the mass-production commodity parts and part families, which typically require dedicated manufacturing facilities. A prototype DFF system for connecting rods of an automotive engine is developed. The system enables the designers to design the connecting rods by considering the fixturing (datums) capabilities of existing manufacturing facilities during the concept design stage, when design parameters are still not frozen. The DFF system analyzes the design with respect to fixturing capabilities of facilities and generates suggestions for the designer, to modify his design if required.