WHAT IS THE ENGINEERING DESIGN APPLICATION

Engineering design applications offer an early explanation and systematic problem-solving techniques applied to specific engineering projects or general design and drafting concepts. The engineering design application in this post guides you through a basic example of an engineering design process, beginning with an idea and a basic sketch and ending with the manufacture of an actual product.

From an Idea to a Product

Design ideas and engineering projects often establish or occur in informal settings. For instance, the engineer of a hand-tool manufacturing company was using a typically adjustable wrench to complete a common home-repair task. While using the wrench, the engineers discovered that it was diffi cult to access a confined location to remove a nut on a piece of equipment. The engineer imagined how the company could design, manufacture, and market a new wrench with features that help make the tool usable in cramped locations. The next day, the engineer and a colleague from the drafting department met for coffee. The engineer sketched the idea for the new wrench on a napkin to communicate the design to the drafter.

The sketch shows the idea of taking the existing tool design and creating a new handle with an ogee, or S-shaped curve design. The sketch communicates the idea of taking an existing tool and creating a new handle with an ogee, or S-shaped curve design

Later the same day, the drafter opens the three- dimensional (3-D) solid model files of the existing wrench design on the computer-aided design and drafting (CADD) system (see Figure).

The drafter copies and then revises the existing design according to the engineer’s sketch (see Figure). The drafter presents the new model to the engineer, who is pleased with the results and requests a rapid prototype. Rapid prototyping (RP) is the process of creating a physical and functional model from a computer-generated 3-D model, using an RP machine, also known as a 3-D  printer. RP machines are available that build prototypes from various materials such as paper and liquid polymer. The hand-tool company does not have an RP machine, so the drafter sends files of the design to a company that specializes in RP. The drafter and engineer receive a prototype two days later.

The figure shows the prototype of the new wrench design. The design team tests the prototype in an application similar to what the engineer experienced at home. The prototype worked as expected.

By the next afternoon, the drafter completes the set of working drawings shown in Figure and sends the drawings to the manufacturing department to manufacture and assemble the new product. The manufacturing department needs lead time to design and make the forging dies required to reproduce the parts. Lead time is the time interval between the initiation and the completion of a production process. Forging is the process of shaping malleable metals by hammering or pressing between dies that duplicate the desired shape. The hand-tool company is small, so the drafter is also responsible for creating catalogue art and copy for marketing the product.

Less than two months after the engineer had the initial idea, the first production run of new wrenches is ready to sell. The figure shows the finished product.