The Engineering Design Process
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The first step leading into a design situation is to identify and define a problem.

Identify and Define the Problem

Somewhere within a company, problems develop that lead to the need for solutions by the engineering design staff. The marketing staff may recognize the need for a new product to help meet competition from other companies. There may be changes in the marketplace that must be met. The down sizing of automobiles in the 1980's is a classic example. An existing product may be obsolete or not functioning satisfactorily and need design attention. These and other factors will generate engineering design problems.

Develop a Work Plan

After the problem is clearly identified, an organized approach to solving it must be developed. While this can involve many factors, the basic questions are:

1. Who is to do the work?
2. What facilities are needed?
3. What will be the cost to develop a solution? and
4. How much time is to be allowed for each segment of the study?

Prepare Solutions and Alternatives

This procedure includes the collection and examination of data, the development of design possibilities, the preparation of alternate designs, and checking the designs for feasibility.

Select a Solution

Of the many possible solutions, the one that appears the most feasible is chosen for development. Sometimes several appear as equal in value, and they all may proceed toward refinement before the final one is chosen.

Design the Product

The goal here is to resolve all design aspects. This could include readjusting the size, shape, motion, or other aspects of the original design. The functional specifications are constantly kept in mind. The final result of the design process is a set of detailed engineering drawings and a revised set of manufacturing specifications.

Test the Solution

Before presenting the solution to the decision makers for approval to begin production, the solution must be tested. The chosen design solution must be carefully analyzed before a final decision is reached. Often, the analysis reveals features that need additional study, and the project is returned to an earlier step in the design process for further consideration. Analysis reveals the feasibility of the recommended design. At this point, the limitations set by the materials available, manufacturing processes, cost, usefulness of the product, its durability, and possible acceptance by the consumer become important. Quite often prototyping or computer simulation occur at this testing stage.

Implement the Final Design

This step involves the preparation of the final engineering drawings, approval of these drawings, and their release for production.

Engineering Design Process in Action:

The International Space Station is placing new demands on the transport and delivery of space station components and personnel to the proposed staging site. With these new demands have come proposed design changes to the existing space shuttle.

Current Design¹

Most of these refinements, already defined through NASA’s Shuttle Upgrade and X-Plane programs, are aimed at improving safety, reliability, and reducing maintenance, turnaround time and weight. The vehicle performance targets they've set are based on:

• a 10-day launch turnaround,

• a $50 million launch cost,

• a passenger/ luggage weight capacity of 40,000 pounds,

• $400 million (each) purchase price on orders of 25-50 vehicles and the capability of 100 flights before major overhauls.

The exterior aerodynamics will remain as close as possible to those of the NASA’s prototypes. The most dramatic design change engineers want to explore is replacing the cargo bay and its doors with a completely detachable passenger compartment able to hold 75 people. Only these compartments would be gently removed and re-inserted by one of the Station OMV's (Orbital Maneuvering Vehicle) .

Proposed Design²

Want to know more? Visit the Space Island Group.

^1&2Courtesy of  Space Island Group

Last Updated June 5/2001