FOR
PRODUCT DESIGN
FOR ENGINEERS
1st Edition
By
DEVDAS SHETTY
All Chapters Arranged Reverse: Chapter 9-1
, Chapter 9 Exercises
9.1 Explain how you would select a team to design a product of multicomponent nature.
What strategies would you use to have an effective design as speedily as possible?
How would you use the prototype design process? Describe two rapid prototyping
methods, identify the benefits of each, and provide sketches.
Characteristics of the Team for a Multicomponent Product
Team Selection
The product design process is of a complex and interdisciplinary nature. Carrying out a
project on product design requires gathering a team of people with diverse expertise. It is
important that the group dynamics of the participants be of the right caliber. The
methodology used by the product team would determine the quality of the final product
and its innovativeness and competitiveness. A good team leader is essential to coordinate
the team members effectively so that the group can remain focused. In selecting a product
design team, various factors to be considered are:
• Composition of team members
• Creation of an environment for design discussions
• Management of the team
• Methodology and approach
Team Quality
The team must have clearly defined goals such as identification of budgets, staffing, and
overall responsibilities. The team has to develop an atmosphere that is conducive to free
thinking. Most importantly, the team must have strong leadership. Teams generally make
better decisions than individuals, especially in situations that are relatively broad and far-
reaching in scope (e.g., strategic planning). Teams should be represented by the
disciplines that are related to the product. Because of the diversity in background,
experience, and skills of the team members, team members are more likely to consider a
wider range of alternatives to solving problems and be more creative in their solutions.
When dealing with sensitive issues, a team has more potential power than any one of the
individuals.
Team Members
Next to the selection of the project, the single most important task is to choose the right
players to serve on the team. As with any type of team, having the right combination of
individual skills, attitudes, and leadership will have a dramatic impact on the outcome of
a project. It is also very important to have a good understanding of how teams should and
can work together in meeting their goals.
Product teams are usually composed of highly motivated individuals from various areas
of the company who may never have worked together. Regardless of whether concurrent
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, engineering is used to develop a new product or process, or to modify an existing one,
some start-up problems must be anticipated. If people in the various functional
departments are comfortable with traditional design approaches, the switch to teamwork
may be difficult. In the traditional approach, each department has a well-defined piece of
action. Each function adds its value as the project is passed from department to
department, often with minimal interaction.
Team Leader
Leaders of multifunctional or cross-functional teams are faced with the challenge of
optimizing team performance. For a successful team, any team project must be preceded
by adequate managerial preparation. An underlying foundation in the concept of
teamwork must be developed within the organization in advance. Picking the right team
leader is absolutely critical to a project’s success. The leader needs to have a combination
of knowledge and qualities that will bring out the best in the team. Some of the qualities
to look for are listed below:
• Respected technical specialist in one functional area;
• Encourages change;
• Strong desires to contribute toward positive change;
• Willingness to listen to ideas of others and to evaluate those ideas objectively;
• Good level of creativity;
• Effective oral communication and persistence; and
• Willingness and desire to work with others in problem solving.
Depending on the size of the team and the resources available, the team leader should
arrange team training. Special training in team dynamics, product economics, and value
engineering techniques will improve the probability of the team’s success.
Strategies for Effective designs are possible when the team makes a concentrated effort
by approaching the problem from many sides. Activities that include alternate designs,
prototyping, and experimentation using additive manufacturing tools must occur
concurrently. Analytical prototypes are representations of the product in a mathematical
manner with computer simulation. Various useful aspects of the product are analyzed.
Some of the tools used are system equations and analysis, graphics based computer
simulation, modeling using visual simulation with hardware in the loop, and computer
models of three-dimensional geometry.
The advantages of 3D computer based prototypes include: the ability to easily visualize
the three dimensional form of design, the ability to automatically compute physical
properties such as mass and volume, and the detection of geometric interference among
parts. Using CAD tools for modeling and simulation of the alternate performance
scenarios can speed up the design specifications. Automotive industries use simulation
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, and modeling in every aspect of automotive design, testing, performance evaluation
procurement, productivity, and integrating management functions.
Use of Prototypes: Prototypes are used in product development stages to ensure that
components and subsystems of the product work together as expected. Physical
prototypes include models that look like the product so that they can be used for the proof
of concept, test the idea quickly, and validate the functionality of the product. Physical
prototypes are useful as integration tools in product development projects because they
require the assembly and physical interconnection of all of the parts and subassemblies
that make up a product. A prototype model of the product can be used as the medium
through which the marketing, design, and manufacturing functions agree on basic design
decisions. Prototypes are used throughout the design process. In the research stage,
prototypes yield test information as well as consumer feedback and performance
comparisons.
Prototypes by Additive Process: The technique, known as additive manufacturing
(because it builds an object by adding ultrathin layers of material one by one), could
transform how the company designs and makes many of the complex parts that go into
everything from gas turbines to ultrasound machines. Additive manufacturing is a major
new development in making rapid prototypes. Aerospace industries, especially the
companies involved in jet engines, are making rapid strides in prototyping. Companies
such as General Electric, Pratt and Whitney, and Rolls Royce are making a radical
departure from the way they have traditionally manufactured things. These companies are
preparing to produce a fuel nozzle for a new aircraft engine by printing the part with
lasers rather than casting and welding the metal. Jet engine makers chose the additive
process for manufacturing the nozzles because it uses less material than conventional
techniques. That reduces the company’s production costs and, because it makes the parts
lighter, yields significant fuel savings for airlines.
Popular rapid prototyping methods are:
• Stereo lithography
• Selective Laser Sintering
• Poly Jet 3D Printing
• Urethane Castings
• Fused Deposition Modeling
• Metal Prototyping
Two rapid prototyping methods are:
1. Stereo lithography (SLA)
2. Selective Laser Sintering (SLS)
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