Manufacturing
Systems
Concurrent Engineering
Concurrent Engineering
Concurrent Engineering:
Is a strategy where all the tasks involved in product
development are done in parallel.
Collaboration between all individuals, groups and
departments within a company.
• Customer research
• Designers
• Marketing
• Accounting
• Engineering
Concurrent Engineering
Suppliers
Commercial
Design Process
Competitors
Customers
R&D
Idea
Generation
Marketing
Product or Service concept
Feasibility
Study
Performance Specifications
Linear Process
Preliminary
Design
Form Design
Revising and testing
prototypes
Functional
Design
Production
Design
Design
Specifications
Manufacturing
Specifications
Pilot run and final
tests
Final Design
and process
plans
Product Launch
Concurrent Engineering
Techniques:
•Perceptual mapping
•Benchmarking
•Reverse Engineering
Concurrent Engineering
Perceptual Mapping
Good
Taste
Coco Pops
Low
Nutrition
Cheerios
Rice Krispies
High
Nutrition
Shredded Wheat
Bad Taste
•Compares customers perception of available products
•Identifies gap in market
Concurrent Engineering
Benchmarking
• Get the best product available
• Base performance specifications for new product
on it
Reverse Engineering
• Dismantle and inspect competitors product(s)
• Select features to incorporate into new product
Concurrent Engineering
Demand for the proposed product?
Cost of developing and producing the product?
Does company have manufacturing capability?
Skilled personnel?
Concurrent Engineering
Form Design: Physical appearance of the product
Functional Design: Performance of the product
Production Design: How to manufacture product
Concurrent Engineering
•Prototype produced
•Adjustments made
•Final specification agreed
Concurrent Engineering
•Manufacturing process commences
•Product is marketed to buying public
Concurrent Engineering
Traditional Process = Linear
Vs
Concurrent Engineering = Team collaboration
Concurrent Engineering
Why Concurrent Engineering?
•Pace of market change has increased
•Companies must keep pace with changing
markets
•Decisions made sooner rather than later
•Reduces/eliminates repetition of tasks
•Reduces waste and reworking of design
•Product quicker to market
•Maximises company profit
•Company operates more efficiently
Concurrent Engineering
To make decisions concurrently:
• Team knows the design goals/objectives
• Team is aware of the interrelationships between
all aspects of the design process
• Superior communication between all sections of
the company
Method:
Quality Function Deployment (QFD)
Concurrent Engineering
Quality Function Deployment (QFD)
Collection of matrices that converts the needs of the
customer into technical specifications at all stages of
the design and manufacture process.
Product Planning (most popular)
•House of Quality
Concurrent Engineering
House of Quality
5
1. Customer requirements
prioritised (scale or %)
2. Competitive product evaluation
3. Engineering characteristics
4. Interrelationships of 1 & 3
5. Relations between engineering
characteristics
6. Targets for new product
3
4
1
6
2
Concurrent Engineering
Example: Water-pond Alarm
1. Identify customer requirement and prioritise them
(scale or %)
Concurrent Engineering
weighting
2. Compare product to competitors
Attribute
Competitive
Assessment
1
2
3
4
Sensitive to water
level
25
B
A
X
Durable
15
A
B
X
Makes a loud noise
10
B
X
A
Inexpensive
25
B
A
Small
10
B
A
X
Looks Good
15
B
X
A
5
X
Concurrent Engineering
Energy Efficiency
25
++
+
Durable
15
Makes a loud noise
10
+
Inexpensive
25
--
Small
10
-
Looks Good
15
Cost of Sensor
Complexity of circuit
Sensitive to water level
Material for casing
Weighting
3.Identify engineering characteristics
Attribute
++
+
+
-
+
--
Concurrent Engineering
Complexity of circuit
Energy Efficiency
Sensitive to water level
25
++
+
Durable
15
Makes a loud noise
10
+
Inexpensive
25
--
Small
10
-
Looks Good
15
Cost of Sensor
Weighting
Legend:
Positive correlation +
Strong positive correlation ++
None
Negative correlation Strong Negative correlation - -
Material for casing
4. Identify strength of interrelationships between customer
requirements and the engineering characteristics.
Attribute
++
+
+
+
--
Concurrent Engineering
Interpreting the matrix
Energy Efficiency
25
++
+
Durable
15
Makes a loud noise
10
+
Inexpensive
25
--
Small
10
-
Looks Good
15
Cost of Sensor
Complexity of circuit
Sensitive to water level
Increasing the noise level could
reduce the energy efficiency
Material for casing
Weighting
Sensitivity to water level is likely to be very dependent on complexity
of circuit
Attribute
++
+
+
+
--
Concurrent Engineering
Energy Efficiency
25
++
+
Durable
15
Makes a loud noise
10
+
Inexpensive
25
--
Small
10
-
Looks Good
15
Cost of Sensor
Complexity of circuit
Sensitive to water level
The choice of material will affect the
durability of the product
Material for casing
Weighting
A complex circuit and quality sensor could increase cost of product
Attribute
++
+
+
+
--
Concurrent Engineering
5. Identify correlation between engineering
characteristics.
Increasing complexity
of circuit could
require a more costly
sensor
Complex circuit
(more parts) could
reduce energy
efficiency
A good quality
sensor could
improve energy
efficiency
Concurrent Engineering
6. Identify targets for new product
120
Target
120
<30
Concurrent Engineering
© 2002 DRM Associates
Concurrent Engineering
Role of CAD in Design & Manufacture
•Model part or assembly being designed
•Part visualised and manipulated on screen
•Realistic
•Function tested
•Textures & lighting effects can be applied
•Photorealistic effects
•Manufacturing drawings generated automatically
•Modelled part and its manufacturing requirements
shared with the entire design and manufacturing team
Concurrent Engineering
Role of CAD in Design & Manufacture
•Geometry from CAD system used to produce part on
CAM system
•CAD model used by marketing to create images for
packaging
•Simulate behaviour of product under stresses and
forces using CAE system
•Model data used by rapid prototyping machine
Concurrent Engineering
Role of CAD in Design & Manufacture
Advantages:
•All above can be done concurrently
•Manufacturing problems identified early
•Changes in design can be seen immediately
•Speeds up design and prototyping processes
Concurrent Engineering
Design for the Environment
There are three major elements of design for the
environment:
•Design for environmental manufacturing
•Design for environmental packaging
•Design for disposal and recyclability.
Concurrent Engineering
Design for Environmental Manufacturing:
•Non-toxic processes & production materials
•Minimum energy utilization
•Minimize emissions
•Minimize waste, scrap & by-products
Concurrent Engineering
Design for Environmental Packaging:
•Minimum of packaging materials
•Reusable pallets and packaging
•Recyclable packaging materials
•Bio-degradable packaging materials
Concurrent Engineering
Design for Disposal & Recycling:
•Re-use/refurbishment of components & assemblies
•Material selection to enable re-use (e.g., thermoset
plastics vs. thermoplastics) and minimize toxicity
•Avoids filler material in plastics such as fibreglass and
graphite
•Minimum number of materials/colours to facilitate
separating materials and re-use
•Design for serviceability to minimize disposal of nonworking products
Concurrent Engineering
Design for Disposal & Recycling:
•Material identification to facilitate re-use
•Design to enable materials to be easily separated
•Design for disassembly (e.g., fracture points, fastening vs.
bonding)
•Avoid use of adhesives
•Limit contaminants - additives, coatings, metal plating of
plastics, etc.
•Maximize use of recycled or ground material with virgin
material
Concurrent Engineering
Impact of Product Life Cycle on the Environment
•Product life cycle = design, manufacture, use & disposal
stages of product
•Minimise a products negative impact on the environment
•Incorporate DfE considerations into design process of a
new product
Concurrent Engineering
Case study 1: Desktop computer
Design Stage:
•The design could specify the following
•Reusable components e.g. monitor, keyboard
•Recycled materials where possible
•Minimise toxic materials used
Manufacture:
•Use ethical work practices and sources for raw materials
•Use ‘clean’ manufacturing processes
•Minimise transport of components and materials
•Implement quality procedures to minimise waste etc.
Use:
•Low power consumption
•Serviceable items rather than replaceable e.g. disk drive, peripherals etc.
Disposal:
•Design for disassembly – use easily dismantled fixings etc.
•Identify materials used for recycling
•Minimise mixed materials to facilitate separation later
Concurrent Engineering
Role of Testing in Product Design
•Cannot predict with absolute certainty how product
will perform
•Need test product before mass production
•Mass production very costly to setup
•Changes cannot be made easily
•Speeds up design and prototyping processes
Concurrent Engineering
Role of Testing in Product Design
Possible tests:
•Product meets performance specifications
•Expected life of product
Accelerated testing
•Likely cause of failure
Concurrent Engineering
Performance test: Pond Alarm
Test
Procedure
Minimum
performance
Casing Seal
Submerge in water for
8 hours
Remove, Dry,
disassemble and
inspect
No evidence of water
ingress
Sensitivity of sensor
Submerge probes to
8mm in sample of pond
water
Retract
Alarm should trigger
before 8mm is reached
Alarm should reset
within 1 min
Battery life
Trigger alarm and
measure time until
battery depletes.
Alarm should sound for
1 hour minimum
Ability to withstand
extreme weather
Place in freezer at 15°C and in oven at
50°C for 1 hour
No damage should be
apparent to casing or
function
Alarm Volume
Trigger in an
unobstructed area then
move away until alarm
is no longer audible
Should be audible up to
30m
Result
Concurrent Engineering
Role of Accelerated Testing
•Used when expected life is long to capture life data
•Life data is needed to estimate the reliability of a product
•Tests are conducted on a sample or prototype
•Tests cause product to fail in same manner as normal use
•Test time is greatly reduced
Product is quicker to market
Low development and warranty costs
Qualitative or Quantitative
Concurrent Engineering
Qualitative Accelerated Tests
•To reveal probable failure modes
•Good tests quickly reveal failure modes
•Improve design product
•Performed on small number of samples
•Product subjected to one severe level of stress
e.g. Stress cycling or hot to cold
•Product intact – pass
•Failure - action taken to eliminate cause of failure
•Only tests conditions encountered in real use
•Cannot be used to quantify life of product
Concurrent Engineering
Quantitative Accelerated Life Tests
•Quantify the life of the product
•Controlled application of accelerated stress conditions
to simulate product failure
•Reduces the time-to-failure for a product
•Data used to estimate reliability of product
Concurrent Engineering
Example:
A washing machine to last for ten years in normal use.
Expected typical household use: three times a week for a wash
cycle that will last for 2 hours on average.
What type of test should be used?
How long must the machine survive during the test?
Total hours life required for the machine is:
2 hours/wash x 3 washes/week x 52 weeks/year x 10 years = 3120
hours
Use a quantitative accelerated test. Run the machine constantly for
3120 hours
Concurrent Engineering
Sample Paper: HL
Explain why accelerated testing is used on some products.
Some products have a long life – need to test reliability
– quantify life of product - warranty
A washing machine will be used for two hours per day, three
days per week in normal use. What type of accelerated testing
will determine the lifetime of the washing machine?
Quantitative test – data is used to determine expected normal life
time of product
During testing, the washing machine ran for 3000 operating
hours before failing. Recommend a suitable guarantee period
for the washing machine and give reasons for your
recommendation.
2hrs/day x 3days/week = 6hrs/week
3000/6 = 566.67 weeks
566.67/52 = 10.8975
Guarantee period = 10 years.