How Feasible is Virtual Prototyping in the CAD World?

Manufacturing organizations have much to gain by reducing TTM (Time To Market), to optimize product designs for optimum performance, and to maximize reliability. A typical product design cycle (before Product Launch), referred to as PLM (Product Lifecycle Management) involves these essential phases:

• Conceptual design,
• Detailed design and validation,
• Tooling design,
• Manufacturing planning and implementation,
• Product build and assembly,
• Reliability Testing.

These essential phases, although they are the preliminary phases of PLM, are time consuming and costly. In a typical PLM, physical prototypes of the end product are produced and tested for functionality, performance and reliability. It usually takes several design and manufacturing iterations to produce acceptable test results before product launch. These are the reasons why preliminary phases of PLM are time consuming and costly.

Virtual Prototyping is emerging as one of the promising methods for creating virtual rather than physical prototypes which can be tested with simulation software. If this method develops into a mature technology, it will provide tremendous benefits to manufacturing organizations.

In order to understand Virtual Prototyping, this article tries to answer these questions:

• How is CAD technology involved in Virtual Prototyping?
• To what extent is Virtual Prototyping being used?
• What benefits does Virtual Prototyping Provide?

How is CAD Technology Involved in Virtual Prototyping?

The goal of Virtual Prototyping is to use engineering simulation software to predict the performance and reliability of product assemblies before they are manufactured. Virtual Prototyping is also referred to as Systems Performance Modeling. The ability to predict the performance and reliability with simulation software is a very complex and challenging task for several reasons.

• It is necessary to understand how components or parts of a product deform individually under loadings, and how they deform when they are assembled into a product.
• It is necessary to understand how material properties of parts degrade over the life of the product. Material properties could degrade due to low or high temperature changes, or due to chemical reactions in a corrosive environment.
• It is necessary to understand the nature of loadings. For example, cyclical loadings occur due to wind forces, ocean wave forces or currents, and earthquakes. A product could also be subjected to vibrational forces created by neighboring machinery.
• It is necessary to understand how manufacturing defects could initiate crack growth and propagation.
• It is necessary to understand failure modes of parts and how they influence the performance of the entire assembly or product in terms of reliability.

Apart from these reasons, there are many other factors to be considered such as governmental regulations, environmental issues, and manufacturing techniques which are utilized for building a product.

The main CAD-related tools which are utilized for Virtual Prototyping are 3D CAD design and simulation tools, and CAE analysis and tools. These tools are capable of designing parts and subjecting them to known static or dynamic loadings, so that they can perform crash simulations and finite element analyses. However, the ability to simulate the performance and reliability of an assembled product under different operational conditions requires more sophisticated software which integrates the capabilities of these CAD tools. This ability is the primary goal of Systems Performance Modeling or Virtual Prototyping.

Successful implementation of simulation software for predicting the performance and reliability of a product will make it possible to examine different design alternatives before committing to specific product intent. If Virtual Prototyping is achievable, the benefits to a manufacturing organization will be enormous. It should be pointed out that the availability of Additive Manufacturing or 3D printing could be utilized to validate simulation software which is developed for Virtual Prototyping.

To What Extent is Virtual Prototyping Being Used?

As complex as Virtual Prototyping sounds, certain organizations have made good progress in implementing the technology. It is worthwhile to look at what has been accomplished.

• Mazda® has been using a Virtual Prototyping solution called the CoMET from Synopsys® for reducing the number of tests on real automobiles for verification of ECUs (Engine Control Units) and HIL test equipment. HIL (Hardware-in-the-loop) is a simulation technique for developing and testing embedded systems such as exist in automotive computer systems (example: suspension, anti-lock braking). Mazda credits the Virtual Prototyping software with accelerating ECU development and lowering cost. Another company which is benefitting from Virtual Prototyping is Ford®.
• Optitex®, an apparel manufacturer, has been using a robust set of virtual fabric simulation software to create, view and edit accurate apparel patterns before putting them on the market. The virtual software provides the company with shorter time to market, improved innovation, and customer satisfaction. For example, design parameters such as fitting, buttons, zippers, pulls, buckles, seam finishes, pleats, repeats, and many more parameters can be manipulated in a virtual environment before the product is made. Another apparel manufacture which is benefitting from virtual prototyping is Tukatech®.

What Benefits Does Virtual Prototyping Provide?

Although many benefits that Virtual Prototyping provides have been mentioned, it will be useful to summarize the most important benefits.

• Virtual Prototyping makes it possible to perform repeatable tests on a virtualized product under conditions which may be difficult or impossible to create.
• Virtual Prototyping makes it possible to perform design modifications on a virtualized product, test the product, and arrive at an optimized design which is cost effective, robust, and reliable.
• Virtual Prototyping makes it possible to test a virtualized product against failure modes and effects, different types of loadings, different operational conditions such as high or low temperatures, customer misuse of the product, and corrosive environments.
• Virtual Prototyping shortens the time for product design, makes it easier to introduce new products, and shortens the time to market.
• Virtual Prototyping provides better customer satisfaction, and increases product presence in the market.

CAD/CAM software systems form an integral part of Virtual Prototyping or Systems Modeling software. Because of the availability of 3D printing, certain types of Virtual Prototyping simulation software should be easier to develop and validate with 3D-printed models.

– IndiaCADworks