From Negative Knowledge to Best Practices for Enhancing Reusability of Sketches in Procedural 3D CAD Models

This paper contributes to advancing the quality of 3D procedural models by proposing practices based on the principle of “how to avoid doing it wrong” derived from analyzing negative knowledge in CAD modeling. The described framework adopts the three levels of quality identified in the literature—usability, reusability, and design intent richness—while focusing specifically on deriving best practices to prevent failures based on negative knowledge related to reusability. The framework is built on the premise that quality issues hindering reusability can be categorized into three interrelated but largely independent types, each affecting the sketches, datums, or features within a procedural model’s tree structure. In this work, the study of sketches is addressed. The negative impact of typical failures, identified through representative case studies that illustrate both design and redesign errors, is analyzed to extract best practices that ensure CAD model reusability. While this study results in a practical guide for avoiding sketch-related errors that compromise the reusability of CAD models, the main contribution lies in demonstrating a framework that transforms negative knowledge into effective best practices.