EMAE260 Final Exam CWRU

Final Exam review

Embodiment Design: Three Basic Rules

Clarity, Simplicity, Safety

Embodiment Design: Product Drawings

Sketches, Detail Drawings, Assembly Drawings, Graphical Models produced in CAD systems

Embodiment Design: CAD v. Sketching-- when to use each?

Use sketching when wanting to develop a high number of ideas. Use CAD when we have details and components and assemblies planned out ahead of time.

Embodiment Design: BOM and what they include

- an index to the product
- the item number or letter
- the part number
- the quantity needed in the assembly
- name or description of the component
- material from which the component is made
-source of the component (purchased?)

Embodiment Design: Difference between mockup, model, and prototype

mockup: to scale from plastics, wood, cardboard to give the designer a feel for their design
-least expensive technique, easy to produce, used as a tool in selling the idea to clients or management

model: the physical behavior of the real system
-proof of product prototype

prototype: most expensive technique that produces the most amount of useful info
-a constructed, full-scale working physical system

Embodiment Design: Design for X (NOT DONE --- GO BACK AND ADD SPECIFICIS?)

Design for manufacture (DFM): establishing the shape of components to allow for efficient, high-quality manufacture
Design for assembly (DFA): the best practice used to measure the ease with which a product can be assembled in terms of efficiency
Design for the environment (DFE): environmentally conscious design

Detail Design: what is and what happens during this phase?

happens:
-make/buy decision
-complete the selection and sizing of components
-complete engineering drawings
-complete the bill of materials
-revise the product design specifications
-complete verification prototype testing
-final cost estimate
-prepare design project report
-final design review
-release design to manufacturing

Detail Design: Product Development Team

Engineering Design
Industrial Engineering
Manufacturing Engineering
Purchasing
Production
Sales and Marketing
Industrial Design

Design Engineering Responsibilities

-detail design performance analyses
-preproduction prototype performance tests
-manufacturing process specifications
-owner manuals
-layout drawings
-detail drawings
-assembly drawings
-bills of materials
-engineering change notices
-patents, trademarks, copyrights

Industrial Design Responsibilities

-product trim details
-finish details
-ergonomic refinements
-product packaging

Sales and Marketing Responsibilities

-product warranty
-shipping
-warehousing
-advertising campaign
-product literature
-owner's manual
-product launch

Industrial Engineering Responsibilities

-materials and product flow
-facility layout/remodeling
-material handling equipment
-inventory warehousing
-assembly planning (machines and workers)

Manufacturing Engineering Responsibilities

-Fixture design/fabrication
-tool design/fabrication
-process equipment refurbishment/adaption
-process equipment acquisition/installation
-process planning

Purchasing Responsibilities

-vendor qualification, selection, negotiation
-outsourcing parts or subassemblies
-raw materials
-materials planning
-quality control
-make or buy

Production Responsibilities

-tooling changeover
-acceptance testing
-worker training
-workforce scheduling

Materials: performance characteristics of metals

metals: strong, ductile, high thermal and electrical conductivity, opaque, reflective

Materials: performance characteristics of ceramics

ceramics: ionic bonding (refractory), brittle, glassy, elastic, non-conducting

Materials: performance characteristics of polymers/plastics

covalent bonding, sharing of electrons, soft ductile, low strength, low density, thermal and electrical insulators, translucent, transparent

Materials: Insensitiive (Instrinsic)

-melting point
-glass transition temp
-density
-porosity
-modulus of elasticity
-coefficient of linear thermal expansion
-thermal conductivity
-specific heat
-corrosion rate

Materials: Sensitive (Exstrinsic)

-strength
-ductility
-fracture toughness
-fatigue properties
-damping capacity
-creep
-impact or shock loading resistance
-hardness
-wear rate or corrosion rate

Durability Properties

Stress & Saltwater causes cracks
heat treatment slows crack speed in salt water

Ductile Brittle Transition Temperature

Mechanical Testing: Tension Mechanical Properties (NEEDS TO BE COMPLETED)

- Young's Modulus
- Yield Strength
- Ultimate Tensile Strength
- Percent Elongation

Mechanical Testing: Hardness

Design for Durability- special cases of design for x

Design for Durability: Fatigue Failures

Fatigue Failures: failures occurring under conditions of dynamic loading.

three stages:
crack initiation
crack propagation
final fracture

Design for Durability: Basic Forms of Corrosion

uniform corrosion: entire surface is cracked
galvanic corrosion: dissimilar metals
crevice corrosion: design issue
pitting corrosion: non-uniform attack
selective launching: dezincification of brass
erosion/corrosion: high velocity fluid
stress corrosion cracking

Design for Durability: Creep

the tendency of a solid material move slowly or deform permanently under the influence of stresses
- time and temperature dependent

Design for Durability: Wear

Match hardness of surfaces
reduce local contact stresses
surface treatments
lubrication
design for alignment

Manufacturing Methods : manufacturing definition and three types of manufacturing industries

the key point is that manufacturing adds value to the material by changing its shape or properties, or by combining it with other materials that have been similarly altered.

Primary: industries cultivate and exploit natural resources
examples: agriculture, forestry, mining, livestock
Secondary: industries convert the output of primary to consumer and capital goods
examples: aerospace, computers, textiles, apparel, construction
Tertiary industries: provide services
examples: banking, communication, education, tourism, transportation

Manufacturing Methods: product quantity/variety tradeoff

key dimensions are: variety of products produced and quantity of each type of product. Is true for both manufactured items and finished goods.

finished goods: (final products) perform a function and are ready for service

manufactured items: (materials, components, and/or supplies) are used in the production of finished goods

Manufacturing Methods: manufacturing capability

technological processing capacity: the available set of manufacturing processes
physical product limitations: refer to size and weight restrictions that can be accommodated
product capacity: refers to quantity in a given period of time

Manufacturing Methods: design for manufacturing

-minimize total number of parts
-standardize components
-use common parts across product lines
-standardize design features
-keep design functional and simple
-design parts to be multifunctional
-design parts of ease of fabrication
-avoid excessively tight tolerances
-minimizing secondary/finishing operations
-use the special characteristics of processes

Manufacturing Methods: design for assembly

-minimize the total number of parts
-minimize the assembly surfaces
-use subassemblies
-mistake-proof the design and assembly
-avoid separate fasteners or minimize fastener costs
-minimize handling in assembly
-minimize assembly direction
-provide unobstructed access for parts and tools
-maximize compliance in assembly

Manufacturing Methods: forming and assembly operations (NEED TO FINISH )

Manufacturing Methods: metal casting methods and metal heating (NEED TO FINISH)

Additive Manufacturing: practical benefits

-negligible geometric constraints
-functionality graded materials
-speeds

Additive Manufacturing: financial benefits

-reduced material waste
-near constant costs (complexity does not drive up the cost of additi

Additive Manufacturing: metal and polymer drawbacks (NEEDS TO FINISH)

Additive Manufacturing: terminology

-build platform: surface which supports the part during production
-coordinate system: z-direction is always perpendicular to the build platform
-layer: the level set of a part created by a plane parallel to the xyz plane; also called a "slice"

Additive Manufacturing: used cases (NEED TO FINISH)

Additive Manufacturing: binder jetting

basic concept: deposit binder in shape of part slice, cover it in powder, repeat

-"binder" is liquid adhesive
-requires post processing
-build platform lowers to accommodate each powder layer

Additive Manufacturing: drawbacks (metal and polymer) (NEED TO FINISH)

Additive Manufacturing: Good Cases

-rapid protyping
-small batch, infrequent production,
-geometrically tedious components
-components that need internal features, such as cooling channels
-in the field production

Additive Manufacturing: Bad Cases

-mass production
-geometrically simple components
-major load-bearing structural components
-components that cannot be tested before being used

Additive Manufacturing: terminology

build platform: surface which supports the part during production

coordinate system: z-direction is always perpendicular to the build platform

layer: the level set of a part created by a plane parallel to the xy plane; also called a "slice"

Additive Manufacturing: Binder Jetting

basic concept: deposit binder in shape of part slice, cover it in powder, repeat

-binder is liquid adhesive
-requires post-processing: sintering, to make the part solid
-build platform lowers to accommodate each powder layer

Additive Manufacturing: Directed Energy Deposition (DED)

basic concept: deposit molten material where it is needed, when it is needed


-'directed energy' is high-power laser
-material propelled forward by stream of inert gas such as Argon
-propulsion gas must be inert, or else material will oxidize during solidification and won't adhere

Additive Manufacturing: Material Extrusion

basic concept: soften (but usually don't liquify) filament by heating it and deposit it where needed:

-most desktop printers are this type
-filament fed mechanically using gears
-normally uses open-air build platform

Additive Manufacturing: Material Jetting

basic concept: spray droplets of liquid material (usually polymer) and solidify them in place


-like binder jetting, but without powder
-needs dissolvable or otherwise removable support material

Additive Manufacturing: Powder Bed Fusion (PBF)

basic concept: melt together regions of power bed in shape of part slice, recoat, repeat

-very similar to binder jetting but material is melted instead of glued together with an adhesive
-must be done in a vacuum chamber or inert gas chamber to prevent interstitial oxidation

Additive Manufacturing: Sheet Lamination

basic concept: apply glue only to part slice, apply next sheet, cut away unglued area, repeat

-usually done with paper
-can be done with metal or polymer films if ultrasonic welding is used to adhere them.

Additive Manufacturing: Vat Photopolymerization

basic concept: use a laser to solidify part slices on top of a liquid polymer vat, lower build platform, repeat

-mostly restricted to polymers, but can be done with an open-air build chamber
-usually regarded as the fastest polymer-based AM available today

Additive Manufacturing: Hall-Petch Relationships

"grain boundary strengthening"

-essentially, more grain boundaries = more internal friction = more resistance to deformation

-related grain size (d) and yield stress (0y)

0y= 0o + [ (ky)/sqrt(d)]

as d increases, 0y decreases and vice-versa

Sustainable Manufacturing: output emissions/products

output emissions: greenhouse gases, various pollutants, toxic chemicals, solid wastes


output products: products, by-products

Sustainable Manufacturing: Embedded Energy (embodied)

the total amount of energy consumed in producing the material or products

Sustainable Manufacturing

the creation of manufactured products that use processes that are non-polluting, conserve energy and natural resources, and are economically sound and safe for employees, communities, and consumers

Sustainable Manufacturing: Benefits

direct benefits:
-reduce cost
-improve profit margin
-reduce environmental impacts (external costs to society)

indirect benefits:
-improve company's image
-aid in green marketing
-market value increase

Sustainable Manufacturing: Drivers

1. economic incentives
-cost saving on energy
-cost saving on materials
-cost saving on manufacturing operations

2. regulatory pressure
-clean air act
-clean water act
-resource conservation and recovery act

3. competitive advantages
-customer preference
-revenues and market share
-positive correlation between environmental performance and commercial success

Sustainable Manufacturing: Obstacles

1. economic barrier
-largest capital cost requirement
-long pay-check period

2. technological barrier
-lack of technologies
-lack of materials
-lack of knowledge
-lack of skilled operators

3. managerial barrier
-lack of understanding from management
-lack of robust data
-lack of decision support tools

Sustainable Manufacturing: emission impacts (NEED TO FINISH)

Sustainable Manufacturing: Nano, Micro, Macro - scale (NEED TO FINISH)

Manufacturing Systems

a collection of integrated equipment and human resources, whose function is to perform one or more processing and/or assembly operations on a starting raw material, part, or set of parts

Manufacturing Systems: production machine types

manually operated machines: are controlled or supervised by a human worker

semi-automated machines: perform a portion of the work-cycle under some form of program control, and a worker tends the machine the rest of the cycle

fully automated machines: operate for extended periods of time with no human attention

Manufacturing Systems: material handling system

-loading work units at each station
-positioning work units at each station
-unloading work units at each station
-transporting work units between stations in multi-station systems
-temporary storage of work units


(load, position, unload, transport, store)

Manufacturing Systems: fixed routing

-work units always flow through the same sequence of workstations
-most production lines exemplify this category
-work stations are usually arranged linearly

Manufacturing Systems: variable routing

-work units are moved through a variety of different station sequences
-most job shops exemplify this category
-a variety of layouts are possible

Manufacturing Systems: Process Layout

-similar activities grouped together in work areas
-suitable for low volume or batch production
-flexible
-not very efficient
-storage space - large receiving, small shipping
-large aisles for movement of materials

Manufacturing Systems: product layout

-arrange activities in sequence of operation
-line set up for one product
-speciliased machines
-suitable for mass production
-more automated than process layouts
-efficient
-line flow
-not flexible

Manufacturing Systems: fixed position layout

-large projects too big to move
-equipment and parts moved in and out of work area
-highly skilled workers-costly

Manufacturing Systems: manning levels

Mi= proportion of time worker is in attendance at station i

- Mi = 1 means that one worker must be at the station continously
- Mi >= 1 indicates manual operations
- Mi < 1 denotes some form of automation

Manufacturing Systems: Capacity Planning - Lead Strategy

-capacity expanded in anticipation of demand
-expects to gain customers from competitors
-"push" strategy

Manufacturing Systems: Capacity Planning - Lag Strategy

-capacity increased after increased in demand
-common where competition is weak
-"pull" strategy

Manufacturing Systems: Capacity Planning - Average Capacity Strategy

-capacity expanded to coincide with average expected demand
-"season goods"

Smart Manufacturing

refers to intelligent automation and data-enhanced production
-artificial intelligence and machine learning
-from process control to factory management to supply chain logistics

Smart Manufacturing: benefits

-know more about everything you produce
-better quality control
-more flexibility

Smart Manufacturing: AI's definition of "intelligence"

intelligent agents should be rational actors

Smart Manufacturing: brute force

-finding all possible paths an agent can take
-works for small problems, completely implodes for large problems

Smart Manufacturing: differences between AI and ML (NEED TO FINISH)

Smart Manufacturing: difference between classification and regression in ML (NEED TO FINISH)

Quality and Robust Design: Quality

-conformance to specifications
-fitness for use
-value for priced
-support services

Quality and Robust Design: good manufacturing practices

-design controls: intrinsic quality established during design phase
-purchasing controls: manufacturer must adequately define and establish requirements
-maintenance and service controls: maintenance and repair data provide insight into performance

-quality system requirements: design, purchasing, and service controls
-clarify record keeping requirements for product failure and complaint investigations
-clarify requirements for qualifying, verifying, and validating processes and specification changes
-clarify requirements for evaluating quality data and correcting quality problems

Quality and Robust Design: control charts

a graphical technique in which statistics computed from measured values of a process characteristic are plotted over time to determine if the process remains in statistical control


indications out of control process:
-sample mean or range are outside UCL or LCL
-trends or cyclical patterns in data
-sudden changes in average values
-points consistently near UCL or LCL
-eight consecutive points that lie on one side of CL
-six consecutive points in which each point is higher (or lower than its predecessor)

Quality and Robust Design: process capability

PC = process mean +- (3 X standard deviation of the process)

assumptions: output is normally distributed
-steady state operation
-process is in statistical control

process capability and tolerances:
-natural tolerance limits - when tolerance is set = process capability

-process capability index
PCI = (UTL- LTL) / (6 X standard deviation of the process)

UTL and LTL are upper and lower tolerance limits

(6 X standard deviation of the process) is the range of natural tolerance limits

Quality and Robust Design: ISO 9000 and

ISO = international organization for standardization

ISO 9000 - standard for the systems and procedures used by a facility that affect the quality of the products and services provided by the facility
(generic: applied to any service/product)

ISO 14000 - focuses on a company's environmental responsibility

Risk, Reliability, and Safety: hazard

the potential for human, property, or environmental damage; unsafe condition that can reasonably be expected to result in failure or injury

Risk, Reliability, and Safety: reliability

a measure of the capability of a part or system to operate without failure in the service environment; expressed as a probability

Risk, Reliability, and Safety: safety

relative protection from exposure to hazards

Risk, Reliability, and Safety: risk and characteristics

the likelihood of a specific effect within a specified period

uncertainty: the risk may or may not happen, there are no 100% risks

loss: the risk becomes a reality and unwanted consequences or losses occur

Risk, Reliability, and Safety: FMEA

a structured approach to identify the ways in which a product or process can fail, estimate risk associated with specific causes, prioritize the actions that should be taken to reduce risk, and evaluate design validation plan

Risk, Reliability, and Safety: FMEA Procedure

1. for each process input determine the ways in which the input can go wrong
- select a severity level for each effect
2. for each failure mode, determine effects
- select a severity level for each effect
3. identify potential causes of each failure mode
- select an occurrence level for each cause
4. list current controls for each cause
-select a detection level for each cause
5. calculate the risk priority number
6. develop recommended actions, assign responsible persons, and take actions
-give priority to high RPNs
-must look at severities rated a 10
7. assign predicted severity, occurrence, and detection levels and compare RPN's

Risk, Reliability, and Safety: SOD

severity: importance of the effect on customer requirements
occurrence: frequency with which a given cause occurs and creates failure modes
detection: the ability of the current control scheme to detect or prevent a given cause

Risk, Reliability, and Safety: Rating Scales

-two types of scales (1-5) or (1-10)
- (1-5) makes it easier for teams to decide on scores
- (1-10) for better precision in estimates and a wide variation in scores

Ethics: IDEK (need to finis)

Design and Manufacturing: Seven Phases of Design

1. Conceptual Design
2. Embodiment Design
3. Detail Design
4. Planning for Manufacture
5. Product Distribution
6. Product Use
7. Product Retirement/Decommissioning

Design and Manufacturing: Types of Design

original/innovative:
-invention
-disruptive
-top of design hierarchy

adaptive:
-known solutions to meet different needs

redesign:
-improve on existing design
-redesign a failing component
-reduce manufacture cost

selection:

industrial:
-improving appeal of a product

Design and Manufacturing: Design Process

step 1: identify the problem
step 2: research problem
step 3: develop solutions
step 4: select best possible solution
step 5: construct prototype
step 6: test and evaluate the solutions
step 7: communicate the solutions

Team Behavior Tools: characteristics of good team members

-take responsibility for success of the team
-deliver on commitments
-be a contributor to discussions
-give your full attention to speakers and ask questions
-develop techniques for getting your message across to the team
-learn to give and receive useful feedback

Team Behavior Tools: characteristics of effective teams

-team goals are as important as individual goals
-team understands goals are is committed to achieving them
-trust replaces fear, people feel comfortable taking risks
-respect, collaboration, open-mindedness
-communication
-decisions made by consensus and have acceptance support of members

Team Behavior Tools: Team Leadership Roles, Definitions, Responsibilities : Team sponsor

the manager who has the need for the output of the team
-provides any special resources needed by team and formally commissions the team