The Design Process

The Design Process

 

Design is the progression of an abstract motion or idea tp something that has a function and a fixed form.  The desired levels of quality and reliability must be “engineered in” during the design phase of a new product.  The design phase is where most costs can controlled.

 

The new product development process is a series of interdependent and frequently overlapping activities which transform an idea into a prototype and on to a marketable product.  The original idea is continually refined and constantly evaluated for technical and commercial feasibility.  Trade-offs between the various objectives (price, cost, performance, market availability, quality and reliability) are made throughout the process.  The changing competitive environment requires that much more planning, coordination, and review take place during the design and development phases.

 

The Investigation or Concept Formulation Phase

 

Most new product design is actually an adaptation or an expanded feature set for a previous design.  Advancing technology process improvements, and market expansion drive the majority of new product desin activity.  The process described is equally applicable to a totally new product or a “new improved one.”

  • Defining the New Product – First, the product is defined, usually with help from marketing.  Marketing translates marketing information in a product definition it believes will satisfy the customer need.  Designers create product designs that they think will meet customer requirements but also future customer expectations.  Supply management gather as much information concerning materials in the supply market that will become the materials used in the new product design.
  • Statement of Objectives – After one defines the new product, a statement of needs, desires, and objectives is developed.  Needs are based on marketing’s perception or knowledge of what customers want (or the customers direct input if the customer is a member of the design team) balanced against the company’s objectives (profit potential, sales volume) and resources (personnel, machines, and management).  Product objectives, including performance, price, quality, and market availability, are established and become the criteria that guide subsequent design, planning, and decision making.  Procurement professionals are the key sources of information on the cost, performance, market availability, quality, and reliability  of supplier-furnished components which may be used in the new product.
  • Key Technology – The development team should determine whether a key technology is involved.  If not, the team may decide to have an outside supplier develop both the technology and the product.
  • Development of Alternatives – Alternatives ways to satisfy these needs, desires, and objectives should be developed and then evaluated against the criteria established.  Alternative approaches should be evaluated on the basis of suitability, producability, component availability, economy, and customer acceptability.
    • Suitability refers to technical considerations such as strength, size, power consumption, capability, maintainability, and adaptability.  Engineering is primarily responsible for these issues.
    • Producability is the ease with which a firm can manufacture an item
    • Component availability is the time at which components are available, while component economy describes the cost of an item or service. Procurement has primary responsibility for component availability and economy.
  • Make/Buy and Outsourcing Analysis – The make or buy and outsourcing issues should be addressed for all new items which can be either purchased or produced in-house.  We covered this in the strategic phase of the course.
  • Select Components, Technologies, and Supplies – Several options may meet engineering’s constraints while offering a wide range of cost, availability, and reliability choices.  The selection of required standard components is facilitated by the availability of a current internal catalog of standard items and sources which have been pre-qualified.
  • Stress Testing and Failure Analysis – Once the candidate component and subsystem items have been identified, they are subject to stress testing and failure analysis.  Every failure has a cause and is a symptom of a failure mechanism waiting top be discovered.  The tools of failure analysis are both statistical and physical.

 

The Development Phase

 

Rapid advances in computer technology and software have made large-scale, complex simulations possible.  Manufacturers typically conduct extensive computer simulations to identify interferences, fit issues, functionality, algorithmic logic accuracy, and so forth, before the development of prototypes.

 

Despite these technical advances, breadboard and/or hardware prototypes commonly are developed so that the design team may conduct tests on the integrated system to eliminate performance problems.

 

  • Prototypes – Protoypes are designed, built, and tested.  Documentation such as materials lists, drawings, and test procedures is created.
  • Design reviews – The design review is the point at which the new design can be measured, compared with previously established objectives, and improved.  Supply ensures that the specifications or other purchase description is complete, is unambiguous, and provides necessary information on how items furnished under it are to be checked or tested.
  • Qualification testing – this test is conducted on protoypes. Ther are two different tests; they are:
    • Margin testing – concerned with assuring that the threshold of failure-the combination of conditions at which the product just begins to malfunction-is outside the range of specified conditions for the product’s use.
    • Life testing – intended to find patterns of failure which occur too infrequently to be detected by engineering tests on one or two prototypes.  These tests differ from margin tests primarily in the number of units tested and the duration of the test.
  • Failure Analysis – The stess testing and failure analysis techniques described in the investigation phase are applied to the prototype.
  • Objective Met? – The design team determines whether the prototype meets the objectives established in the investigation phase. If the prototype fails this analysis, the project reenters the design process and a new or upgraded prototype is developed.
  • Value Engineering – using substitutions for more expensive tooling and parts specifications.

Value Engineering vis-à-vis Value Analysis – Value Engineering (VE) is a systematic study of every element of cost in a material, item equipment, service, or construction project to ensure that the element fulfills a necessary function at the lowest possible total cost.  Two tools aid those involved in the VE process:

  • Design Analysis – entails a methodical step-by-step study of all phases of the design of a particular item in relation to the function it performs.  The philosophy underlying this approach is not concerned with the appraisal of any specific part per se.
  • The Value Engineering (VE) Checklist – Most companies develop some type of checklist to systematize the value engineering process.  Here is an example of a value engineering checklist:
    • Can the item be eliminated?
    • If the item is not standard, can a standard item be used?
    • If it is a standard item, does it completely fit the application, or is it a misfit?
    • Does the item have a greater capacity than is required?
    • Can the weight be reduced?
    • Is there a similar item in inventory that could be substituted?
    • Are closer tolerances specified than are necessary?
    • Is unnecessary machining performed on the item?
    • Are unnecessarily fine finishes specified?

There is a general procedural model for the value engineering process.  The elements of the model are:

    • Information Phase – define and price the function and obtain and interpret all the facts.
    • Speculation Phase – generate new ideas and determine alternative solutions.
    • Analysis Phase – determine and compare feasibility, suitability, and costs.
    • Decision and action phase – review key alternatives, select best alternatives, get department and manager approvals, and prepare new specifications
    • Evaluation phase – audit the effectiveness of the selection and use operating experience to effect further improvement
  • Viability – Before proceeding to production, a careful business analysis must be completed.  The development team asks: “Will the product provide our firm’s required return on investment?
  • The Production Phase
    • Manufacturing and Production Plans – a firm finalizes its manufacturing plan (in the form of a bill of materials) and procurement plan.
    • Knowledge Transfer – Manufacturing applies experience from similar projects and new developments from other manufacturers to the firm’s production process.  Manufacturing engineers also work with suppliers to share new and improved production techniques.
    • Process control – Suppliers and buyer finalize the process to produce the product. Changes at this stage can be very expensive.
    • In-process and final testing – There are two objectives for in-process testing: (1) adjust or calibrate the performance in some way and (2) eliminate defects before much value is added to the product.  Fianl product testing ensures that item meets its performance objectives.

 

Engineering Change Management

 

Engineering change management is a discipline to control engineering changes.  When engineering change management is used, changes are controlled and recorded.  Marketing and all activities involved in the purchase, control and use of purchased materials are told about any proposed changes to an item’s characteristics.