CADModelScope: Revealing the Dependency Structure Behind Parametric Computer-Aided Design Models

Paper Title

CADModelScope: Revealing the Dependency Structure Behind Parametric Computer-Aided Design Models

Publication Info

• Topic area: Visualization and navigation of parametric CAD model dependencies.
• Keywords: Parametric CAD, dependency visualization, modularization, design intent, graph-based tools, CAD navigation, operation dependencies, user study, Autodesk Fusion, CAD debugging.

Background and Problem

• Problem / challenge: Parametric CAD models rely on hidden interdependencies among operations, which are obscured in commercial CAD systems. This makes navigation, debugging, and modularization of complex models difficult and error-prone.
• Significance: Understanding and managing operation dependencies is critical for efficient design workflows, error resolution, and collaboration in CAD, especially for large and unfamiliar models.
• Motivation and related work: Prior efforts to visualize dependencies in CAD systems have been limited by visual clutter, lack of interactivity, and insufficient user-centric evaluations. Existing tools do not effectively support tracing, modularization, or error resolution in complex models.

Solution

• Proposed approach: CADModelScope, a multi-level graph-based visualization tool integrated into Autodesk Fusion, reveals hidden operation dependencies to support navigation, modularization, and debugging.
• Novelty:
  1. Multi-level visualization of operation dependencies, including global, local, and modular views.
  2. Clustering of interdependent operations into functional modules.
  3. Interactive synchronization with the native CAD interface for seamless navigation.
  4. Empirical evaluation of the tool's impact on user workflows.
• Procedure and key techniques:
  1. Construct a directed acyclic graph of operation dependencies, with nodes representing operations and edges indicating dependencies.
  2. Implement three views:
     • Operation Overview: Global dependency graph with node size indicating downstream influence.
     • Local Dependency View: Interactive tracing of upstream and downstream dependencies for a selected operation.
     • Modular View: Clustering of operations into functional units using the Louvain algorithm.
  3. Synchronize the tool with Autodesk Fusion’s UI for real-time interaction and highlighting.
  4. Evaluate the tool through a user study with tasks reflecting navigation, modularization, and error resolution.

Results

• Concrete findings:
  • CADModelScope improved structured navigation and modularization of CAD models.
  • Participants using the tool achieved higher accuracy in modularization tasks (mean accuracy = 0.859 vs. 0.761 without the tool).
  • Dependency-aware workflows enabled targeted error resolution and reduced reliance on exhaustive search.
• Advantage over baselines:
  • Reduced cognitive load and navigation overhead compared to native CAD features.
  • Enabled context-aware exploration of dependencies, which was not possible with traditional tools.
• Experiments / evaluation:
  • Conducted with 8 participants (mechanical engineers with CAD experience).
  • Tasks included navigation, modularization, and error resolution in complex CAD models.
  • Mixed-method evaluation combining task performance metrics and qualitative feedback.
• Limitations and future work:
  • Limited to part modelling; future work could extend to assemblies.
  • Clustering results occasionally misled users; future iterations could integrate user-defined semantics.
  • Study used publicly available models and a modest participant sample; larger-scale and longitudinal studies are needed for generalizability.

Summary

CADModelScope addresses the challenge of visualizing hidden dependencies in parametric CAD models by providing a multi-level graph-based tool integrated into Autodesk Fusion. The tool enables structured navigation, modularization, and error resolution through interactive dependency visualizations. A user study demonstrated its effectiveness in improving workflows compared to native CAD features, particularly for complex and unfamiliar models. Future work could extend the tool to assemblies, incorporate user-defined semantics, and evaluate its impact in more diverse and realistic design contexts.