Adapting Binary Decision Diagrams for Visualizing Product Configuration Data

Abstract

This paper deals with the challenges of visualizing and understanding complex interacting Boolean formulæ for selecting parts in an automotive Bill-of-Materials (BoM). Our approach targets entire BoM positions containing all variants of a part, each with its own selection formula. A part variant is needed for a car if the selection formula evaluates to true under the option list (feature list) which defines the car variant. Understanding the formulæ is critical when editing or when trying to analyze and explain a bug, but it is non-trivial. SAT-solving is commonly used to detect bugs, but explaining the cause of bugs is a different matter. Our approach is to visualize all selection alternatives in a single diagram based on an adaptation of binary decision diagrams (BDDs). We also visualize the influence of the configuration constraints for car variants on the selection diagrams and show how they can help to reduce their size. Based on this method we implemented a visualization tool which additionally serves as a visual formula editor.