Mechanical design drawings, whether paper or electronic, have traditionally been at the center of the product development universe. But as more and more companies transform into model-based enterprises (MBE), a model-based definition (MBD) methodology needs to be adopted by mechanical engineering departments to make this a reality.
Here are five fundamental concepts they should keep in mind.
A model-based enterprise is the management and use of sets of models and simulations by the whole enterprise to accelerate product development.
A Brief History of the MBD Evolution
To understand MBD, let’s start at the beginning. Mechanical product design and development is historically based in the manual creation of drawings. This means collaboration with the rest of the enterprise includes manually interpreting drawings to derive information. Therefore, drawings are the definitive definition of the product.
As mechanical CAD (MCAD) technology becomes more robust, product design becomes increasingly model-based, and 3D models become the foundation of the product definition.
Teams recognize the potential of using model data to augment drawing information to improve efficiency. This usually means companies are using both a drawing and a model as the mechanical engineering data set for a product.
Here’s where problems arise. There is increased risk when 3D models and drawings are used outside of mechanical engineering. The concept of MBD was developed to address immature data management practices around using MCAD models and drawings as a data set and uncontrolled data derived throughout the enterprise.
MBD policies and methods ensure the value of complete data sets (3D models and derived data) as the product definition.
To truly make the transformation to MBE, the data set must be complete, accurate, under control and managed as the basis of enterprise collaboration and reuse. The data must be easy to access and trusted by users, so that adoption is widespread.
This transformation is anything but easy.
Five Fundamentals of a Transformation to MBD in the Mechanical Engineering Space
The transformation to a model-based enterprise is a journey. Here are five things that are fundamental to your success:
Ensure visible executive support and governance
Shift Focus from Capturing Design Intent Information on the 2D drawing to the 3D model
Visible executive support and transparent governance are the simplest ways to enable the transformation to MBD. Lack of executive support or governance limits the initiative before it even gets started. Executives must proactively justify the need for change, communicate the organizational benefits to users, announce progress, manage expectations and use a clear governance process that removes barriers and allows change adoption in all impacted functions of the organization. Visible leadership also helps minimize the temporary productivity dip during the transformation.
Shift Focus from Capturing Design Intent Information on the 2D drawing to the 3D model
Many businesses assume that MBD is about eliminating drawings; that’s not the case. MBD is focused on capturing the complete design intent into the 3D model. MBD makes sure the complete
design intent is captured in the 3D model. This includes traditional drawing details usually captured in notes. Information could include tolerance information and material information in a manner that is human AND machine readable.
By capturing the complete design intent in the 3D model, a single source of truth is established. This single source of truth can be leveraged to create derived data, like drawings, to ease human readability to aid design partners and suppliers that are not set up to work purely with 3D models. These drawings are typically much simpler and function more as a window into the design intent instead of as a method to capture additional design intent. It is imperative that any derived data is managed in lockstep with the 3D model managed throughout the product’s total lifecycle – from initial concept to disposal.
This begins with creating a common set of templates for parts and assemblies that include pre-defined views to improve human readability. The user will need to use the appropriate actions in their modeling application to capture GD&T and PMI that can be understood by downstream applications, like manufacturing and inspection systems, as well as by people in the organization.
Common templates and settings help ensure that standards are universally applied and followed. While some users may complain their creativity is limited, changing configuration settings does not restrict creativity. Users should continue to focus on creating innovative products.
You must establish and hold the enterprise accountable to standard CAD practices. What should be included in a CAD standard? It should include leading practices for modeling, creating derived data and change management. An enterprise should document best techniques and conventions used within the organization.
Standards for CAD use are important enablers of MBD, but they do not provide value without holding users accountable through enforcement. CAD without standards will cause serious problems anywhere people try to reuse data or make business decisions based on it. CAD standards set clear expectations and allow consistent CAD documentation.
Bottom line: standards encourage trust in the data, which reduces overall development time. This trust starts in engineering.
Designers and engineers will complain about standards. They are likely to suggest that complying with standards takes extra time and effort. The perceived extra time and effort ensure the job is done right. However, if you consider the time wasted repeatedly reinterpreting and fixing data, doing things right the first time saves time across the enterprise.
Accountability is extremely important; without it, nobody will comply with the standards. There must be a system of approvals. If a job does not meet the expectations and needs, it can’t be released.
It’s also important to remember that adhering to good CAD practices does not mean you have a good design. A good design must meet customer expectations and industry mandates. A customer doesn’t really care what your design method is or how complete your data is. But enforcing standards will help make sure the customer’s quality expectations are met, and your co-workers will appreciate the consistency.
Communicate the Benefits Across the Enterprise
The most common MBD benefits are reduced changes in product designs and an overall reduction in product development time. Reported improvements range between 25 to 50% reductions for both measures. Other benefits include efficiencies gained by increasing the reuse of datasets and the reduction of product nonconformance and recall risk.
Quantifying these benefits that take place largely outside of engineering is difficult. Corporate scrap/rework or product recall costs are closely held proprietary information. However, a review of recent headlines suggests that the financial impact of product liability and product recall costs could be massive, easily dwarfing any cost associated with implementing good MBE methodologies.
It is important to note that MBD benefits are dependent on the existence of a functioning product lifecycle management (PLM) system. The assumptions are:
MBD data sets are managed in a PLM system throughout release and change
The data standards are enforced assuring good quality at release and during subsequent change management.
Prepare for a Culture Change
The transformation to a model-based enterprise is largely an exercise in culture change. Any change this significant requires executive enablement and an active governance process that acts to protect the investment and improve the value of PLM and CAD tools.
Culture change is made in small steps, not big jumps. Don’t get caught in the “eliminate drawings” hype. Be aware of the high expectations and plan reasonable steps in MBD maturity.
Enterprises should be prepared to make sure that the best techniques and conventions are used throughout the organization and ensure that expectations are clear, so all users behave in a consistent manner. It is also important to repeatedly communicate progress and benefits. Communication must be tailored to the different audiences across the enterprise and is best delivered in multiple forms.
Culture change is hard work, but hardly impossible
Companies must transform into model-based enterprises or fail to realize the full value from their digital investments. Model-based enterprises require data and process disciple—frequently overlooked changes in a transformation.
Keeping in mind these fundamental concepts can help ensure your organization's successful transformation.
Howard manages projects in the firm’s PLM practice with clients in life sciences, discrete, high tech and A&D industries. He works with organizations that have complex products and development environments that leverage his deep design and manufacturing experience.