Getting Designs off to a Better Start: Conceptual Design

By barb schmitz | Published: June 3, 2011

The very earliest stage of product development, the conceptual phase, plays a very critical role in the eventual success of a new product. Choosing the wrong concept can lead manufacturers down a path to increased design complexity, mandatory redesign, missed deadlines, and growing product cost, and at its worst, can literally bankrupt a business. Assumptions and decisions made at this stage will have a tremendous impact on the product’s design, manufacturing and life so selecting the right concept is probably the most crucial decision manufacturers will make.

During the conceptual stage, engineers and designers rapidly explore and refine ideas. Design participants will engage in free-flowing collaborative brainstorming, exploring a range of design options—in the form of sketches, 2D drawings and layouts, and 3D models—until a final concept design is chosen. Concepts can be start out as designers sketching on paper, though eventually more realistic models need to be created to mimic the function, movement, and look of the real product.

The concept phase, however, isn’t simply a group of people ogling over highly stylized rendered images of concept designs. In many industries, like industrial equipment, aerospace and defense, etc., functional requirements outweigh the importance of aesthetics and styling. In these cases, the design team must take into account the functional requirements of the design (design intent), along with customer needs, manufacturability, environmental issues, and BOM cost issues. In some industries, such as high tech or consumer goods, the functional requirements may be secondary to styling issues, such as curved, sweeping surfaces.

Design intent is the intelligence that defines the fit and function requirements of the product. The ultimate success of the final product hinges upon design intent being captured early; encapsulated in the concept model and maintained throughout the design cycle—all without stifling creativity. Pie-in-the-sky concepts won’t hold up well during the mechanical design process when limiters like physics, mathematics, manufacturability, industry standards, and customer requirements come to bear.

One common mistake is focusing in on one concept too early in the process, often due to outside pressures (marketing demos needed for trade shows, consumer retail cycles, R&D budgets, and competitors).  The result is often bad design decisions, forcing designers, now committed to a concept, to work around complications as they rear their ugly heads throughout the rest of the development process.

In order to prevent such disasters, manufacturers need to really take their time during this crucial phase. Don’t narrow in on one concept too soon and assign multiple designers to flesh out multiple concepts concurrently. Then have several concepts detailed to the point at which the design team can determine with the highest level of confidence, which designs will work. After all, if a design isn’t going to fulfill its design requirements, this is the time to find out.

Tools of the Trade

To facilitate this iterative process, engineers must have the design tools that are very flexible as design concepts at this stage are fluid, changing often. Once created, proposed design concepts—whether in the form of sketches, 2D drawings or 3D models—must be reviewed by the extended design team and perhaps customers, and refined quickly based on their input.  Iterations should be constant at this stage so the design tools must be easy and intuitive enough to be used by non-CAD specialists as well. Often these tools may be different from the MCAD tools used during the detailed design phase.

When conceptual models are handed off to the engineering team and recreated in a MCAD system, not only does this lead to inefficiency in recreating what already exists, but often designs often change dramatically.  This misinterpretation of concept models is often caused by a communication gap between conceptual or industrial designers and the mechanical engineers tasked with creating the 3D CAD model on which the final product will be built. This disconnect between the design/styling team and the rest of the product development team often leads to loss of design intent as designs progress through the design cycle.

One way to mitigate this risk is to choose a suite of design tools that span both concept and detailed design stages. By offering bi-directional interoperability, these tools can reduce the risk of this communication gap and eliminate the need for engineers to reinterpret or re-create designers’ conceptual models, safeguarding design intent and facilitating the re-use of design data so mechanical engineers are not starting from scratch once concept models are approved.

When conceptual design tools and MCAD tools have interoperability with each other, mechanical engineers can simply bring approved sketches, drawings, even 3D concept models into their CAD software and then get to work further refining the model into a true 3D digital model or virtual prototype that can be ultimately designed, tested, and built.

Improving Product Quality

By barb schmitz | Published: June 29, 2011

 

Product development engineers and designers are human, and as we all know, to err is human, right? Unfortunately in the increasingly competitive world of product design, making errors in the design of a new product can cost a company plenty in the form of costly reworks, expensive recalls, lost development time, lost revenue and possibly customers, if bad products make their way to market. Increased liability and warranty costs add to the pressure manufacturers face to reduce errors.

One way to head off potential problems is to shift design verification and validation methods from the end of the design process to the beginning of development, when errors are fixed with the least expense and effort. At this point, designs still reside in digital form so they are easily changeable and should be iterated continuously to assure the design is fully optimized. After all, design validation is most useful when there is time in the development cycle to integrate the results back into the design.

Sometimes this is difficult to do, however, because performing a complete design validation is a detailed, methodical, and time-consuming task. The key is to use design methodologies and tools that focus on ‘what if’ type analysis early in the design cycle, without derailing development schedules. Design verification and validation are both crucial steps in ensuring that a new product will ultimately meet, or possibly exceed, customers’ needs and expectations.

Integrating verification and validation early in the design cycle delivers significant returns: improved product quality, reduced prototyping costs, and shortened design cycles. Design verification assures that products fulfill the requirements specified for them, while validation confirms that a product will fulfill its intended use or purpose. In other words, verification assures that the product was built correctly, while validation assures that the manufacturer built the right product.

Both processes—verification and validation—provide periodic confirmation that the design is headed in the right direction, reducing the chance of designs making a wrong turn, in terms of meeting design requirements and specifications, which could lead to further errors down the line when changes come at a much higher cost, both in terms of time and money.  Verification and validation provide engineers with a variety of possible feedback or output that they can incorporate back into the design. This feedback might include whether or not the design met requirements or specifications; descriptions of failure modes; summarized test results; and recommendations for improvement.

The first step is to determine the means by which the requirements will be validated. For some manufacturers, especially those who manufacture electromechanical products, this step will involve identifying the testing required for mechanical, electrical, and embedded software as well as the system as a whole. Testing facilities and resources must then be secured, and physical tests run or digital models developed and simulations run.

Design requirements are translated into a set of test cases with loads and constraints that can either be measured physically or digitally across all functional domains (electrical, mechanical, and software). Once the tests and simulations are run, the results of both the physical or digital tests are documented in reports, indicating whether the product satisfied both its requirements and specifications.

Implementing verification and validation techniques—either digitally or physically—early in the design process enables engineers to ask the “what if” questions when the answers bear the most fruit. Having the answers to all those questions empowers engineers to make the best decisions that guide designs in the right direction from the start and ultimately result in better, higher-quality products.

What a Concept: The Importance of the Early Phase of Design

By barb schmitz | Published: August 5, 2011

The preliminary stage of any new product development project is the conceptual design phase. During this early stage, engineers and designers rapidly explore and refine ideas by engaging in free-flowing, collaborative brainstorming sessions, during which a wide range of designs—in the form of sketches, 2D drawings and layouts, and 3D models and renderings—are considered and evaluated until a final concept design is collectively chosen.

During this time, ideas might be sketched roughly on white boards or on paper. A recent study entitled, Trends in Concept Design, conducted by PTC, illustrates the methods by which concept designs or ideas are captured. According to the survey, the largest percentage of the survey’s 214 participants (27%) indicated that concept designs are captured electronically in the form of 3D data, however following closely another 21% of participants indicated that concepts were more often shared via hand-drawn sketches on paper.

Regardless of how the ideas are captured, the concept phase of design is the time to assemble a company’s brightest minds to generate ideas, which in turn, are evaluated, mutated, blended and reincarnated. The most innovative ideas are generated by iterating back and forth between by multiple sources, filtering them through each participant’s various perspectives until a proposed design is agreed upon.

Carefully identifying the final product’s requirements (design intent) is extremely important at this stage, as it will serve as the sieve through which product ideas must be funneled through to assure the product will meet its objectives. As ideas are evaluated, they must be analyzed for adherence to goals and requirements. Companies must also realistically assess their current technology and whether it is sufficient to accomplish the design and manufacture of the proposed product.

Another reason why the concept stage is a critically important phase of new product design is because this is when of the majority of the total development costs is committed. According to the American Association of Mechanical Engineers (ASME), nearly 75% of the manufacturing cost of a typical product is committed by the end of the conceptual phase, meaning that only 25% of a product’s cost can be influenced by decisions made after this time.

The PTC survey, which was conducted in July 2011, backs this statistic, with results showing that 61% of participants saying that 61% of a product’s total development costs are fully committed at this stage of design. Another 43% say that 71% of the total product cost is fixed by the time they exit the conceptual design phase. As a result, if decisions made during this early phase of design are bad, manufacturers stand to lose much of the money that was committed before production even starts.

Good Concepts Take Time

One common mistake manufacturers make is focusing in on one concept design too early and rushing to get designs into the detailed design stage, often due to outside pressures from management and sales and marketing personnel.  According to the PTC survey, 67% participants indicated that they spend less than 30% of their total product development time on the conceptual design stage.

The result is often bad design decisions that carry hefty downstream costs when design issues arise during latter stages. In order to prevent such disasters, manufacturers need to really take their time during this crucial phase and afford their designers the sufficient time to evaluate multiple ideas and designs.

According to the PTC survey, 71% of respondents said that they explore and evaluate between two and five concept designs before moving to the detailed design phase of development. Of that group, nearly half (49%) explore only two or three concept designs. While there is no magic number of concept models that should be evaluated prior to moving proposed designs forward, designers should have the tools and the time to evaluate as many designs as possible.