Computing Design Rationales Using Causal Representation of Simulations

We present a new system for computing design rationales of geometric features on mechanical devices. Our system interprets dynamic simulations of mechanical devices and automatically generates an English text document for the purposes of the geometric features on the device. To identify the purpose of a particular feature, we simulate the behavior of the device with and without the feature present. We then represent each simulation with a causal representation we developed. Differences between these two representations are indicative of the feature’s purpose. Since the computed differences are already in the form of causal explanations of behavior, they can be directly translated into English text descriptions of the feature’s purpose. Finally, we discuss enhancements on explanations using geometric reasoning and configuration spaces.