This element involves the final tradeoffs of design
details and manufacturing capabilities to arrive at a final detailed design
configuration that will enable on-time, error-free, affordable production. As
in error-proofing the design (see 4.2), optimizing
manufacturing is a goal. The objective is to continuously improve both product
design and process capabilities. During the detailed design phase, trade
studies can assist in arriving at an optimum balance of quality,
functionality, cost, performance, and producibility. Most of the techniques
used to trade conceptual designs (see 3.3
can now be used to assess detailed designs.
In this step, prototypes are manufactured or purchased,
testing is conducted, and simulations of the planned manufacturing processes are
evaluated. Virtual prototypes and the use of simulations can reveal changes
required prior to any actual manufacturing. Physical prototypes can be tested
extensively to provide data to support the achievement of the design goals as
well as for process control variables. Process maturity, ease of assembly, and
manufacturing risk continue to be key elements considered during these final
trade studies. Prior to final design release, it is appropriate to review the
manufacturing plan for the design to attempt to identify improvements.
Prototyping of product and process, using either real mock-ups or computer
simulations, can assist in identifying opportunities for improvement.
Factory floor, assembly, and process simulation tools can
provide a cost-effective evaluation of the manufacturing plan before any product
is manufactured. Manufacturing system simulation may be used to model the
overall production process, material flow, and schedules, while process
simulations help predict the outcome between individual processes and the
Advances in solid modeling and improvements in computer
performance make it possible to perform a comprehensive analysis of virtual
parts and to assess the capability of processes before actual manufacturing
begins. Tolerance analysis tools allow users to simulate different tolerance
stack-up conditions that are likely to occur during a manufacturing process.
Modeling software also allows designers to model the behavior of mechanical
systems under real-world conditions.
Case Studies 40 and 41
in Appendix D are examples
pertinent to a discussion on optimizing manufacturing.
Improving manufacturing before production begins can
result in more efficient and effective processes.
manufacturing engineers, industrial engineers, and simulation support staff.
Tools and Techniques: The tools used in the tradeoff studies begun in 3.3
are also applicable here. Such tools include Benchmarking, DFMA, Modeling and
Simulation, Prototyping, and Rapid Prototyping. In addition, Manufacturing
Simulations are suitable for analyzing the entire factory floor operation
before production, and Root Cause Analysis (RCA) is helpful in identifying
inherent problems in either products or processes and in determining possible
corrective action. These tools are shown in Figure