What Does MBD Mean?

Editor's Note: This post was originally published in 2020. It was updated in July 2024. 

Model-Based Definition, or MBD, is the practice of documenting the information necessary to manufacture and inspect parts, assemblies, and products in 3D Computer Aided Design (CAD) models, as opposed to traditional 2D-production drawings. (Note that ASME Y14.47, Model Organization Practices, considers MBD to be “an annotated model and its associated data that define the product in a manner that can be used effectively without a drawing graphic sheet.”)

If you aren’t exploring MBD, there’s a good chance that other companies in your market are taking advantage of it and gaining a competitive advantage. MBD is both a proven process and consistently growing trend, empowering companies to reduce cost and time-to-market while improving product quality. 

To explain MBD, this blog will discuss benefits, the implementation process, Technical Data Packages, the Model-Based Enterprise, and how Creo can support your MBD endeavors.

What are the benefits of MBD?

MBD provides numerous benefits to the product-development process. Some examples of real-world performance improvements include:

• Jabil increased number of projects by 400%
• Vaillant improved first-pass yield by 53%
• MBDA Missile Systems experienced 42% faster product development
• Nidec reduced Cost of Poor Quality by 40%
• Volkswagen decreased time-to-industrialization by 25%

MBD is more efficient than the traditional 2D-drawing method because the 3D annotations in the CAD model are semantic. This means that downstream software for Computer Aided Manufacturing (CAM) and Coordinate Measuring Machines (CMM) can understand what the annotations mean, and more importantly, the geometry references that they apply to. This eliminates unnecessary data translation or transcription, resulting in the following benefits:

• MBD speeds up the design–manufacturing–inspection cycle
• It reduces errors and the Cost of Poor Quality (COPQ)
• Teams increase their productivity and efficiency

From 2D drawings to MBD

Many companies are still drawing-based. They develop a 3D model, generate a 2D-production drawing, and then share a PDF with their supply chain. 

Engineering organizations can realize immense benefits and savings by eliminating drawings and going right from design to manufacturing. This means capturing Product and Manufacturing Information (PMI) directly in the 3D model, like:

• Dimensions and linear tolerances
• Geometric tolerances, Datum Feature Symbols, and Datum Targets
• Notes
• Symbols
• Surface finishes
• Tables like title blocks, revision blocks, and Bills of Material (BOM)

Standards for MBD are captured in ASME Y14.41-2019, ISO 16792:2021 and MIL-STD-31000B.

Implementing MBD

If CAD users already know how to create 2D drawings, the transition to MBD is easy. Many organizations can get their engineers and designers started in MBD in less than an hour. You don’t have to reinvent your organization to reap the benefits of MBD. You can start a pilot on a single development project, with near immediate benefits in development time, cost, and quality.

The main elements of MBD in the CAD model are:

• Annotation Planes to define the placement and orientation of the details to be placed in the model
• The 3D Annotations for the PMI
• Combination States to organize the 3D Annotations for clarity and organization

Combination States also include:

• Simplified Representations to control which components in an assembly are visible
• Cross Sections to see the interior of parts
• Explore States showing how components in an assembly fit together
• Appearance States to show different colors and textures for parts. This can be helpful when explaining fabrication or assembly steps
• Style States to display various components in wireframe, hidden line, no hidden line, shaded, or transparent. Configuring different styles for different components enhances visualization for users.

The deliverable: Technical Data Packages

One common misperception is that MBD is “drawing-less” or “paperless.” MBD means the drawing is no longer the primary source of truth. When necessary, you can create a drawing if your supply chain requires it. 

Instead of a PDF, the primary deliverable from MBD is the Technical Data Package (TDP). This is a set of electronic files that can include the following:

• The model either in its native Creo Parametric format or the CAD-neutral STEP AP242 format
• The Bill of Materials (BOM)
• Requirements and specifications
• Schematics for electronics and cables
• Software documentation
• First Article Inspection (FAI) sheets and other quality documentation

The TDP will be your single source of truth for your engineering definition.

The journey to MBE

After companies implement MBD, they can progress toward becoming a Model-Based Enterprise (MBE). This represents a product-development organization that has taken MBD beyond the engineering department into manufacturing, the internal and external supply chain, quality, service, and beyond. Achieving MBE optimizes and streamlines your core processes, enabling you to maximize efficiency and profits.

Continuous innovation with Creo

With every version, PTC invests significant resources into Creo’s MBD functionality and workflows. Recent enhancements include:

• Tables that can be created manually using a Creo table file or imported from Excel
• General Profile Tolerances (GPT) that apply to all surfaces that do not have geometric characteristics explicitly defined. GPT automatically collects all semantic references, allowing the user to focus on GD&T critical to safety, quality, and performance.
• Standards compliance with ASME Y14.5, ISO 1101, ISO 22081, ISO 13715, and ISO 21204
• Streamlined workflows for placing and editing Symbols and Surface Finishes
• Assembly support within the GD&T Advisor

Get Started with MBD

MBD streamlines the product-development workflow because it generates content that can be utilized downstream in manufacturing, supply chain, inventory, and across the enterprise. 

Are you ready to improve your efficiency and reap the benefits of MBD? If you are, check out ourfree eBook below on how to embrace more efficient processes for a competitive advantage.