manufacturability
Extent to which a good can be manufactured with relative ease at
minimumcostand maximumreliability.
Definition of 'Value Engineering'A systematic and organized
approach to provide the necessary functions in a project at the
lowest cost. Value engineering promotes the substitution of
materials and methods with less expensive alternatives, without
sacrificing functionality. It is focused solely on the functions of
various components and materials, rather than their physical
attributes. Also called value analysis.Investopedia explains 'Value
Engineering'The concept of value engineering evolved in the 1940s
at General Electric, in the midst of World War II. Due to the war,
purchase engineer Lawrence Miles and others sought substitutes for
materials and components, since there was a chronic shortage of
them. These substitutes were often found to reduce costs and
provided equal or better performance.
Manufacturability & Value EngineeringMay 27, 2012
bymohamedalb502and taggedAutomobile
Platform,Cars,Manufacturability,Modular
Design,MQB,Standardization,Strategy 2018,Value
Engineering,Volkswagen,VWWe learned in our Operation Management
class that designing operations processes aims to reduce cost;
reduce complexity; additional standardization of components;
improvement of functional aspects of the product; and improved
maintainability of the product. Furthermore, manufacturing and
value engineering procedures are concerned with improvement of
design and specifications at the research, development, design, and
production stages of product development. Also, we learned that
organizations develop a strategy plan to set their expectations of
achieving missions and goals.Volkswagen(VW) Group set a strategic
plan known as Strategy 2018 that aims to make the VW Group a
worldwide leader in 2018. Over the long term, VW aims to increase
unit sales to more than 10 million vehicles a year and intends to
increase its return on sales before tax to at least 8%. To achieve
these goals, Volkswagen announced an introduction of new
manufacturing design platform calledModular Transverse Matrixor
(MQB), which will play a vital role.Volkswagen Group is a German
multinational automotive manufacturing group headquartered
inWolfsburg. It is the worlds second-largest motor vehicle
manufacturer by2011 unit salesand the largest based in Europe. The
Group is made up of various big brands: Volkswagen, Audi, Porsche,
Bugatti, Lamborghini, Bentley, Skoda, SEAT, VW Commercial Vehicles,
Scania and MAN.Generally, eachautomobile platformis designed
specifically for a market segment and shared between cars of
similar size. A typical mass market of VW platform underpins
different brands with several model variants. VW is now creating
shared modular platforms to serve needs of its different
subsidiaries. One of the prominent features of the MQB is the
uniform position of all engines designed to accommodate two new
four cylinder engine cars. The new engines will reduce the Groups
engines and gearbox variants in the MQB system by 90% and the MQB
will also enables an identical mounting position for all current
alternative drive concepts from natural gas and hybrid versions to
the pure electric drivecitation.Soon, all of the models and brands
under VW Group will be produced on the same assembly line, and even
will produce MQB models of different brands together. The
advantages of creating amodular designare: simplifications of
manufacturing and assembly; easier repair and replacement; parts
interchangeability; standardization; and easier diagnosis and
remedy of failures. By creating a standardized, interchangeable set
of parts from which to build a variety of cars, VW plans to cut the
time taken to build a car by 30%. The MQB platform will allow the
VW Group to produce a worldwide high volume and niche models at
extremely competitive costs over the long term. The MQB takes
advantage of synergies in key technologies and allows for greater
boost in salescitation.The modular platform concept is a radical
structural advantage for Volkswagen Group in the global automotive
industry, allowing it to reduce costs and be more competitive on
prices. Do you think that Volkswagen Group cars will dominate the
world market share by 2018?
--
How product design can create production quality issuesbyRENAUD
ANJORANon23 OCTOBER 2010Today I was in a factory of silicon
products (cookware, phone covers). My client was buying the cover
for a TV remote control. Production started earlier this week, and
I was called in urgently to find solutions to production quality
issues.The defect rate was roughly 40% Because a world-class
product designer came up with a cool-looking 3D blueprint, because
a TV network operator approved it, and because the importer
confirmed it could be done.The beauty of China is that one can get
a production running with very cheap moulds, which allows for a lot
of flexibility and lower quantities per design. The drawback is
that these moulds require lots of manual operators, which means
more opportunities for defects.The factory put in place a complex
process: Injecting liquid silicon in different colors in one mould;
Heating the liquid silicon to get it into a solid state; Cleaning
throughly around the silicon by rubbing and by blowing air; Putting
another piece of solid silicon on top, and doing the
compression/moulding operation; Getting the piece of silicon out of
the mould (it was basically all around the mould).Each operation
creates its own defects. And some defects simply cannot be avoided.
For example, the liquid silicon is not hard enough (in my opinion)
and gets spread around a little with the solid silicon is
compressed.How to sold this issue? The temperature can hardly be
modified (below 210 degres is not advised for silicon), and the
warming time cannot be increased (or some pieces dont stick to the
mold any more).All I could do is reduce some opportunities for
defects by correcting some behaviors (and I am not even sure what
they will do once I am gone) and by doing some tests.But the
fundamental issue is that such a design cannot be done properly in
China. One needs highly automatic molds that cost many times more
money.This type of problem is no doubt encouraged by the distance
between a French product designer and a Chinese factory that will
be sourced after the project is approved. It is just not the way to
proceed The best designers, in my mind, should be familiar with the
production constraints, or at least have a dialogue with factory
technicians.In some industries, so much has been achieved with such
cooperation They usually call it DFMA (Design For Manufacturing and
Assembly).--
What is robust product design?Robust product design is a concept
from the teachings of Dr. Genichi Taguchi, a Japanese quality guru.
It is defined as reducing variation in a product without
eliminating the causes of the variation. In other words, making the
product or process insensitive to variation. This variation
(sometimes called noise) can come from a variety of factors and can
be classified into three main types: internal variation, external
variation, and unit to unit variation. Internal variation is due to
deterioration such as the wear of a machine, and aging of
materials. External variation is from factor relating to
environmental conditions such as temperature, humidity and dust.
Unit to Unit variation is variations between parts due to
variations in material, processes and equipment. (Lochner and
Matar, 18). Examples of robust design include umbrella fabric that
will not deteriorate when exposed to varying environments (external
variation), food products that have long shelf lives (internal
variation), and replacement parts that will fit properly (unit to
unit variation). The goal of robust design is to come up with a way
to make the final product consistent when the process is subject to
a variety of "noise".How do you make a design robust?Taguchi
considers making a design robust in the parameter design portion of
product or process design. In parameter design the goal is to find
values for controllable settings that minimize the negative effects
of the uncontrollable settings. Experiments are used to determine
the impact of particular settings on both the controllable and
uncontrollable factors. The idea here is that by observing changes
in a controllable factor (such as the thickness of boards), a value
can be found for that factor that reduces the effect (warping) of
something that cant be controlled (the humidity outside). The
ultimate goal is to find the optimal settings to minimize cost by
minimizing variation.When setting up these experiments, the factors
that effect the product need to be determined. Then the factors can
be separated into controllable factors and uncontrollable factors
and experiments can be set up to test the effects of changing the
values of each factor. There are many ways to set up these
experiments. Taguchis method involves finding correlation between
variables. He uses orthogonal arrays, with the inner array
consisting of control factors and the outer array consisting of
"noise" factors. Each inner array is to be run with each outer
array. (If six control factor experiments and three "noise" factor
experiments are needed, there will have to be (six times three)
eighteen experimental trials to get all the combinations).Another
method for conducting these experiments is to make no attempt to
control the "noise" factors, but repeatedly run the trials for
combinations of control factors. (Lochner and Matar, 152) This type
of experiment allows the operator to measure process variability.
The trials should be taken in an environment similar to the one in
which the actual use or manufacturing of the product is going to
take place. A third experimental design is to identify all the
control and "noise" factors (adding the control and noise factors
yields k) and run an analysis using at least k +1 trials based on
eight-run experiments. (You could use an eight run experiment for
up to k=7, and a sixteen run experiment for up to k=15.) This will
allow the interaction between variable to be seen running fewer
tests than using Taguchi's method. Further instruction as to how to
use this method is found in chapter four of "Designing for Quality"
by Lochner and Matar.The data found from the experimental trials is
then analyzed. The analysis will depend on the method of
experimentation. Plot the effect that the variables had on your
variation and/or the correlation between factors. Using this data
find settings for the controllable factors that are found to lower
the variation caused by uncontrollable factors.Then after the
initial experiment trails are run and "optimal" settings are found
confirmation experimentation is needed. By performing a series of
replica experiments at the levels that were picked, we can see if
the values achieved matched that of the values the model predicted.
If there is disparity, there may be an interaction or noise that we
didnt see and thus our experiment must be redeveloped.What are the
advantages of robust design?Robust design has many advantages. For
one, the effect of robustness on quality is great. Robustness
reduces variation in parts by reducing the effects of
uncontrollable variation. More consistent parts equals better
quality.Another advantage is that lower quality parts or parts with
higher tolerances can be used and a quality product can still be
made. This saves the company money, because the less variable the
parts can be the more they cost.A third advantage is that the
product will have more appeal to the customer. Customers demand a
robust product that won't be as vulnerable to deterioration and can
be used in a variety of situations.This method is also good,
because you are designing the robustness into the product and
process instead of trying to fix variation problem after they
occur.What are the disadvantages of robust design?One of the
disadvantages of robust design is that to effectively deal with the
noise, the designer must be aware of the noise. If there is a noise
factor that is affecting the product and the experiments run do not
address it (intentionally or not), the only way that the product
will be robust to that variation is by luck.Another disadvantage to
robust design done Taguchis way is that the problem becomes large
quickly. If you had a lot of different things to consider as
control variables and/or noise variables, it would take a great
deal of time to run all the experimental trials. Controlling noise
variables is expense, and when lots of trials are required the
dollars add up.Another disadvantage is that by using orthogonal
arrays, it assumes the noise factors are independent, which may be
helpful in setting up the experiment, but is not necessarily a good
assumption (Lochner and Matar, 153).What are some examples of why
robust design is important?Consider this example adapted from
"Creating Quality" by Kolarik; the designers of a radio had built
and tested a breadboard. After the radio was considered a success,
the specifications were passed to production and the radios began
being manufactured. The first production units radios went into
test and failed to meet marketings product performance
requirements, as did the second unit. Analysis of why the process
failed produced no results. They had been following procedure and
using standard acceptable parts. Next the breadboard of the
original design was inspected. It was found that the designers had
hand-tested and picked all the component parts. They worked much
better than the manufacturers standard acceptable parts. After
review of the design it was found that there was no way to
economically fix the problem without massive redesign, so personnel
were assigned the task of manually sorting the components, costing
the company additional time.In this example the design of the radio
needed to be robust so that it could handle the amount of variation
in the set of standard acceptable parts. Because the design didnt
allow for that amount of variability, it cost the company lost
time. They had to stop the production process and investigate and
then they had to expend further manpower in screening the
parts.Making a product robust is also a concern for companies that
manufacture products for an ever-expanding market. If products are
sold nation wide or even globally, the differences in the
environments, conditions, and uses have to be considered for them
to be a success. For example, a manufacturer of a certain type of
gas grill that is sold nationally must consider the robustness of
the materials used to make the grill. The people in Minnesota may
use the grill in the summer only and it is stored in the garage in
the winter where the temperature falls to freezing. The consumers
in Arizona use the grill year round and it is stored on the deck
where it is subject to sunlight, rain and higher temperatures. The
manufacturer must make sure that the grill can withstand both
conditions. If the freezing temperature cracks the valve connection
or if the heat cause the lid to deform, they will lose the
potential buyers in the respective area.What can be said in
conclusion?Robust design is designing a way to make the final
product consistent when the process is subject to a variety of
"noise". This can be done through a variety of experimentation
methods. The results are capable of showing how to develop a
product/process that will be robust. The advantages of robust
design are that the products are of good quality, cheaper, and more
customer friendly than their non-robust counterparts. Although
there are disadvantages, having a robust product design can give
companies a large competitive edge.--Modular designThe term modular
design basically means a design of components that can be assembled
in a variety of ways to meet individual consumer needs. This can be
something like a pre fabed home where different sections can be
combined to make the home they need.
There are so many modular design examples that are all around
us. A good example that we can all relate to of a modular design
example is car. When you need some customization and additional
features, you will need to pay a little bit more. Modular designs
are meant to offer customers an extensive range of satisfaction.
This has proved to be of so much benefit to consumers since they
are able to choose from various options available to them.
--CADCAD (computer-aided design) software is used by architects,
engineers, drafters, artists, and others to create precision
drawings or technical illustrations. CAD software can be used to
create two-dimensional (2-D) drawings or three-dimensional (3-D)
models.CAD/CAM(computer-aided design/computer-aided manufacturing)
is software used to design products such as electronic circuit
boards in computers and other devices.CAD / Computer-Aided
DesignComputer-aided design (CAD)is the use of computer programs to
create two- or three-dimensional (2D or 3D) graphical
representations of physical objects. CAD software may be
specialized for specific applications. CAD is widely used for
computer animation and special effects in movies, advertising, and
other applications where the graphic design itself is the finished
product. CAD is also used to design physical products in a wide
range of industries, where the software performs calculations for
determining an optimum shape and size for a variety of product and
industrial design applications.In product and industrial design,
CAD is used mainly for the creation of detailed 3D solid or surface
models, or 2D vector-based drawings of physical components.
However, CAD is also used throughout the engineering process from
conceptual design and layout of products, through strength and
dynamic analysis of assemblies, to the definition of manufacturing
methods. This allows an engineer to both interactively and
automatically analyze design variants, to find the optimal design
for manufacturing while minimizing the use of physical
prototypes.Benefits of CADThe benefits of CAD include lower product
development costs, increased productivity, improved product quality
and faster time-to-market. Better visualization of the final
product, sub-assemblies and constituent parts in a CAD system
speeds the design process. CAD software offers greater accuracy, so
errors are reduced. A CAD system provides easier, more robust
documentation of the design, including geometries and dimensions,
bills of materials, etc. CAD software offers easy re-use of design
data and best practices.--CAMCAM / Computer-Aided
ManufacturingComputer-aided manufacturing (CAM)commonly refers to
the use of numerical control (NC) computer software applications to
create detailed instructions (G-code) that drive computer numerical
control (CNC) machine tools for manufacturing parts. Manufacturers
in a variety of industries depend on the capabilities of CAM to
produce high-quality parts.A broader definition of CAM can include
the use of computer applications to define a manufacturing plan for
tooling design, computer-aided design (CAD) model preparation, NC
programming, coordinate measuring machine (CMM) inspection
programming, machine tool simulation, or post-processing. The plan
is then executed in a production environment, such as direct
numerical control (DNC), tool management, CNC machining, or CMM
execution.Benefits of CAMThe benefits of CAM include a properly
defined manufacturing plan that delivers expected results in
production. CAM systems can maximize utilization of a full range of
production equipment, including high speed, 5-axis, multi-function
and turning machines, electrical discharge machining (EDM) and CMM
inspection equipment. CAM systems can aid in creating, verifying,
and optimizing NC programs for optimum machining productivity, as
well as automate the creation of shop documentation. Advanced CAM
systems with product lifecycle management (PLM) integration can
provide manufacturing planning and production personnel with data
and process management to ensure use of correct data and standard
resources. CAM and PLM systems can be integrated with DNC systems
for delivery and management of files to CNC machines on the shop
floor.--What is Virtual Reality?Virtual reality can be defined as
an upcoming technology that makes users feel in aVirtual
Environment(VE) by using computerhardwareandsoftware. It was
originally conceived as a digitally created space which humans
could access by donning special computer equipments. It enables
people to deal with information more easily. VR provides a
different way to see and experience information, one that is
dynamic and immediate. For example, in a computer game,
usersjoystickmotions are tracked and the objects in the game are
moved according to the joystick movements. In the same way a
simulated, three-dimensional world is created around the user in
which he/she could interact with objects, people, and environments.
Typically three-dimensional life-sized images with support of audio
devices are presented around the user and the perspective is
modified in accordance with the user input (generally head or eye
movements). Many devices along with the computers are used to
create a virtual environment.To enter in a VE, a user dons special
gloves, earphones, and goggles, all of which send their output to
thecomputer systems. The virtual environments are intended to
replace the real world environment with the digital one and the
human senses are immersed in the VE. Immersion is an experience of
losing oneself in the VE and shutting out all cues from the
physical world. A Virtual Environment can be created on different
extents depending on the computer based platform ranging from a
cell phone screen to a desktop monitor or a fullyImmersive Virtual
Environment(IVE).The tracking and rendering turns the whole process
more immersive and interactive than the traditional media like
televisions and video games. The user actions result in immediate
and observable impact on the content of virtual environment.
Following are the main components of a virtual environment:1.The
visual displays that immerse the user in the virtual world and
block out contradictory sensory impressions from the real
world.2.The graphics rendering system that generates the ever
changing images at 20 to 30 frames per second.3.A tracking system
that continuously informs the position and orientation of the users
movements.4.The database construction and maintenance system to
build and maintain a detailed and realistic model of the virtual
world.5.A sound system that can produce high quality directional
sounds and simulated sound fields.6.Devices like tracked gloves
with pushbuttons to enable users to specify their interactions with
the virtual objects.How VR worksA simple example of Counter Strike
game can give a thought as tohow virtual reality works. The
software program for the game is the major element which runs with
the help of the computer system and the interfaced input output
devices. Every Character and environment within the game behaves
closely to reality as per the code written for them. The code
facilitates characters and environment to interact with the other
characters controlled by the input devices. The code is interpreted
by the processor which handles the input output devices
accordingly. This is the simplest example of how VR works. The
working of more immersive virtual reality environment is quite
similar to working of the game besides the fact that a number of
advanced input and output devices along with a high performance
processor are added to increase the immersion. The processor
executes the processes quickly according to the input given by the
user and output is presented to the user in a way that user feels
itself a part of the environment and its objects. The video below
shows an example of more immersive virtual reality.The 3D
visualization component enables the user to see 3D scenarios by
using a display methodology like a head mounted device. Typically
the 3D images superimpose the real environment by using one of the
display, screen based or projection based. The screen based virtual
environment generally uses a high quality display screen in terms
of resolution and color, or a head mounted device along with the
sound system as output devices. A keyboard, microphone, head
tracking sensors, finger trackers,gesture recognition system,
ajoystickor similar gears are used as input devices. When user
moves the gear or joystick, make move of the head, or press any key
on the keyboard, the objects of the screen are changes accordingly
in a way that user feels if he/she is directly controlling the
objects and environments on the screen. A high speed powerful
processor processes the inputs. An Application Programming
Interface (API) provides the interface to the input devices
connected to the system as well as to standard devices like mouse
and keyboard. The timings and relationship between input and output
devices are so perfect that user feels an immersion with the
virtual environment.The other technique used to create a virtual
environment is projection based, which is more immersive than the
screen based method. The display images are projected on the multi
screen spaces ranging from two to six screens. A six screens would
make a better virtual environment.Both floor and ceiling uses a
rear projection while the other four screens yield large
surrounding views for both panning actions and looking down.
Consequently objects inside the space could be walked around and
virtual entreat to be touched.
