- The paper introduces a hybrid modular DFM that selects the best manufacturing process for individual modules to enhance overall part manufacturability.
- It employs quantitative manufacturability indexes and octree decomposition to assess both global and local design challenges.
- The study demonstrates significant reductions in machining difficulty and improved efficiency in industrial tooling through its validated methodology.
A Novel DFM Approach Integrating Machining and Additive Manufacturing
The paper "A new DFM approach to combine machining and additive manufacturing" by Olivier Kerbrat, Pascal Mognol, and Jean-Yves Hascoët introduces an innovative Design for Manufacturing (DFM) methodology that integrates both additive and subtractive manufacturing processes. The primary focus is on enhancing the manufacturability of parts by addressing the complexity of various manufacturing approaches at the design stage.
The authors propose a hybrid modular vision where parts are considered as assemblies composed of individual modules. This perspective allows for the selection of the most suitable manufacturing process for each module, thereby optimizing for time, cost, and quality. The key advancement here is the ability of the proposed DFM system to evaluate multi-process manufacturability, which is a gap in existing systems that often cater to a single manufacturing process.
Manufacturability Evaluation and Indexes
The paper discusses the need for a comprehensive manufacturability evaluation during the design stage. It categorizes manufacturability assessments into binary, qualitative, and quantitative scales, with emphasis on quantitative measures for multi-process environments. To aid in the evaluation, the authors introduce manufacturability indexes, which are derived from design parameters such as geometry, dimensions, and material properties. The indexes are bifurcated into global and local categories, providing a detailed analysis of manufacturing difficulties.
The authors utilize octree decomposition for a nuanced local manufacturability assessment. This technique allows for high-resolution analysis of geometrically complex areas, thus facilitating informed decision-making on process selection.
Hybrid Modular Design Methodology
The paper outlines a structured six-stage hybrid modular design methodology. Starting with a one-piece CAD model, the manufacturability is assessed, followed by hybrid and modular approaches to address manufacturing challenges. Subsequent iterative modifications in design allow exploration of alternatives to optimize manufacturability. Comparative analysis of the manufacturability indexes between one-piece and modular designs effectively quantifies improvements.
Implementation and Industrial Validation
The authors implement the methodology in SolidWorks using Visual Basic, enhancing the integration of this approach into existing design workflows. This implementation allows for the automation of manufacturability assessments and the comparison of alternative designs through exported Excel files.
The methodology was validated through studies on industrial tooling parts, specifically focusing on injection molds and automotive dies. Results demonstrated substantial reductions in manufacturing complexity, evidenced by decreases in manufacturability index values. Notably, in the case of an automotive die, transitioning to a hybrid design led to a significant reduction in machining difficulty in previously challenging areas.
Implications and Future Developments
The implications of this research are substantial for industries employing both additive and subtractive manufacturing techniques. By reducing manufacturing complexity, the hybrid modular DFM approach can lead to cost savings and improved production efficiency. The capability to accurately assess manufacturability during the design phase also leads to more informed decisions, potentially reducing lead times.
The authors acknowledge potential future developments, including the incorporation of additional manufacturability indexes derived from material properties and technical specifications. They also emphasize the need to integrate assembly constraints into the methodology to ensure that modular assemblies meet quality standards comparable to one-piece designs.
This paper presents a thoroughly developed approach to manufacturing design, expanding on traditional DFM by incorporating emerging technologies and methodologies. As manufacturing processes continue to evolve, such hybrid methodologies will likely become more integral to design practices, promoting efficient and flexible manufacturing solutions.