Design Thinking Final
Spatial Constraints
"envelope" of a product - products have to fit in a particular area, products have to be used in a confined area
High Quality Product
"its quality measure stay on target regardless of parameter variation due to manufacturing, aging, or the environment" Works as It Should, Lasts a Long Time, Easy to Maintain
Procedural or Process Knowledge
"knowing what to do next"
Deliverable
"thing" that the parties involved my be ready for deliver from the design team to the decision makers on a certain date.
Form
(physical product) The shape, color, texture that the product takes
How to come up with a reasonable factor of safety?
1. Build high fidelity models 2. carry out empirical testing when feasible, understand the materials used, 3. understand the solid mechanics, loading, etc based on geometry and how the forces are applied
3 Main Charges of Negligence
1. Design defects 2. Design did not include proper safety devices 3. Designer did not foresee possible alternative uses of the product
Three Phases of Product Definition
1. Discover what projects to do 2. Choose which projects are worth spending time and resources pursuing 3. Plan how to spend time and resources on the project
Ways to mitigate risk
1. Document all considerations in the design process 2. Use commonly accepted standards 3. Use proven evaluation techniques for proving the quality of design before it goes to production 4. Follow a proven, rational design process.
Canons of Engineering Ethics
1. Hold paramount the safety, health, and welfare of the public 2. Perform services only in areas of their competence 3. Issue public statements only in an objective and truthful manner 4. Act for each employer or client as faithful agents or trustees 5. Avoid deceptive acts 6 Conduct themselves honorable, responsibly, ethically, and lawfully so as to enhance the honor, reputation and usefulness of the profession
Failure Modes and Effects Analysis (FMEA)
1. Identify the Function Affected 2. Identify Failure Modes 3. Identify the Effect of Failure 4. Identify the Failure Causes or Errors 5. Identify the Corrective Action
Steps for Helping to Simulation/Physical prototype decision
1. Identify the Output Responses that Need to be Measured 2. Note the Needed Fidelity 3. Identify the Input Signal, the Control Parameters and their Limits, and Noises 4. Understand Analytical Modeling Capabilities 5. Understand the Physical Modeling Capabilities 6. Select the Most Appropriate Modeling Method 7. Perform the Analysis or Experiments and Verify the Results.
Evaluation of Product Performance
1. Must result in numerical measures of the product for comparison with the engineering specifications and targets 2. Should give some indication of which product features to modify and by how much in order to meet the targets 3. Procedures must include the influence of variations due to manufacturing, aging, and environmental changes
Cost, Quality, and Time to Market
3 Measures of Design Success
Technology Push
A new technology is developed before there is a customer demand
refining
Activity of making an object less abstract
Functional Decomposition Techniques
Aids in further refining the functional requirements
Concept Variant Generation
Aids in transforming the functions to concepts
Professional Society
An organization that seeks to develop a particular profession through research, skill development, scholarships, etc
Creeping Specifications
As the project progresses, the specifications change, resulting in delays, added costs, and sometimes the complete redesign of a product
Guidelines for DFS
Be aware of the environmental effects of the materials and processes used in products; design the product with high separability; design components that can be reused/recycled, Be aware of the environmental effects of the material not reused or recycled.
Reshaping
Changing the shape of something to lead to creative and space saving solutions.
Nominal Length
Changing this usually does not increase the cost substantially
Selective Design
Choosing a product or object from already existing possibilities
PDP - Product Development Process
Clear procedure for planning and managing product design projects - each company has their own name, acronym, and process for it
Market Pull
Customer demand for new products or features
Stage Gate PDP
Decision "gates" between design stages which are defined; Gates are generally design reviews
Morphology
Decompose the function, develop concepts for each function, and combine concepts.
decreases
Design freedom _______________ as knowledge of the design problem increases
Redesign
Design of a new product starting with the design of a currently existing product
Modular Design
Design of one component to improve flexibility and allow for the integration of new technology
Design for Sustainability (DFS)
Design the product to have low impact on the environment throughout the entire life cycle of the product
Design for Test and Maintenance (DFT, DFM).
Design the product to make it easy to diagnose problems and perform maintenance; ex is a car check engine light
Why you should update models that were used earlier in the design process
Designers gain a greater understanding of the actual function and how the user interacts with it; functional problems can be detected
Sensitivity Analysis
Determines which parameters are most important in terms of product performance; often tested with a rough prototype
How to come up with a reasonable combined factor of safety
Develop factors of safety for the various aspects that contribute to the overall factor of safety, then combine them.
Designer
Develops CAD models for the system
Technician
Develops the testing procedures and apparatus
Assembly Drawings
Drawing to show how the components fit together, refers back to the Bill of Materials
Detail Drawings
Each individual component is drawn with all dimensions, with materials and manufacturing detail. Follow format for standard developed by the company
Contradictions
Engineering trade offs, (making a part stronger by adding material also makes it heavier)
Sources of Variation in operating the Part
Environmental (heat, moisture, etc), user induced, age and wear.
Magnifying/minifying
Exaggerating the size or number of a feature often increases understanding of the feature and its limitations and constraints
Parametric Design
Finding values for the features that characterize the object being developed
Closure Style
Flexible (going with the flow and being adaptive, making it difficult to make a decision) or Decisive (making decisions with minimal stressed in a scheduled/controlled manor)
Stress
Force applied over a cross sectional area; force/area
Spiral PDP
Generally suited to software, initial prototype is developed very rapidly, spiraling outward towards a better product but revisits each stage during this process. (alpha, beta, version 1.0)
TRIZ - Theory of Inventive Machines
Gives 40 principles that are generic suggestions for developing a new product using predictable patterns
Quality Control
Has training to ensure that the product is manufactured according to specification
Proof of Product Prototype
Helps refine the components and assemblies, often done through 3D printing
Design Maturity
How long the design has gone virtually unchanged
Concept
Idea that is sufficiently developed to evaluate the physical principles that govern its behavior
Variant Design
Improving a design that already exists
Trade-Off Management
Improving one performance metric can often cause a decrease in another
Noise Parameters
In contrast to controllable parameters, impossible to control or can be controlled only at a prohibitive cost.
Domain specific knowledge
Information on the form or function of an individual object or a class of objects
General Knowledge
Information that most people know and apply regardless of their expertise and experience
Energy Source
Internal or External (Introversion or Extroversion)
Manufacturing Engineer
Knows the manufacturing capabilities of the company and what other capabilities are available in the industry
Waterfall PDP
Linear process where each stage is "like a place for water to pool before going to next stage"
Bill of Materials
List of parts with the manufacturer, part number, part description, supplier, quantity, and cost
Stiffening (types of patching)
Make something more rigid (or less depending on need)
Deliberation style
Making decisions either objectively (logically or analytically) or subjectively (relying on interpersonal involvement or circumstances)
Extrusion
Manufacturing process of forming that forces material through an opening and creates a shape
Pressing
Manufacturing process of forming that involves bending metal using a large press and some type of mold
Stamping
Manufacturing process of forming that involves pushing a shape through a sheet of metal to stamp out a part; uses shearing to cut through the metal
Evaporating Cloud
Method for resolving contradictions
Design for Cost (DFC)
Minimize the overall cost of producing and selling the product
Additive Manufacturing
Opposite process of machining, material is added in thick layers building up a part from nothing Originally called rapid prototyping, now called 3D Printing Can also be used with titanium and biological materials in the near future.
Design for Manufacture (DFM)
Optimize the design to make manufacturing efficient, low-cost, and high quality
Design for Assembly (DFA)
Optimize the design to simplify the assembly procedure
Fixed Costs
Overhead costs and tooling and equipment that is only purchased one time
Basic P-Diagram
P stands for Product or Process (could be a subcomponent), evaluates product on various parameters (see slides for drawing, April 22)
Margin
Percentage above actual cost that the company sells the product
Prior Action (TRIZ)
Perform required changes to an object completely or partially in advance.
Analyst
Performs mathematical analyses to model system performance
Prototypes
Physically building and testing an actual version of the product, ,provides better data on actual performance but is often time consuming and expensive
Casting
Pouring molten material into a mold and allowing it to harden to produce a part Pros/Cons: - Ability to create complex shapes quickly -molds are expensive, so it is more cost effective for large lot sizes -metal is not as strong as forged metal
Decision Matrix Method
Powerful method for comparing alternatives when making any decision. Metrics are all quantitative, so you can sum them up and give one score.
Informational Management Style
Preferring to work with facts or possibilities
Configuration Design
Preliminary selection of materials and manufacturing processes
Design for Reliability (DFR)
Produce products that will be of high quality and last a long time
Variation
Quantifying the difference between instances of the same product (when manufacturing multiple instances of the product, each instance differs slightly from every other instance)
Engineering Specifications
Quantitative, measurable, criteria that the product is designed to satisfy. Must contain a metric, target value, and engineering units for the target value (discriminatory, measurable, orthogonal, universal, and external)
Information Language
Receiving information verbally (through words or equations) or visually (through pictures, diagrams, graphs, prototypes, etc).
Machining
Removing material through drilling holes, making screw threads, simply removing material to make a shape
System Definition Review (SDR)
Report at the end of the conceptual design phase, examining the proposed system architecture and functional elements
Critical Design Review (CDR)
Report that demonstrates that the technical effort is on track to complete the product
Systems Requirements Review (SRR)
Report that occurs at the end of the product definition phase, and ensure the functional and performance requirements will satisfy the needs
Preliminary Design Review (PDR)
Report with the designs proposed, evaluated, and one chosen, outlining next steps for budget, timeline, and product testing
Industrial Engineer
Responsible for the product's aesthetics and how it interacts with the consumer
Decision Matrix
Score alternative concepts on how well the meet each of the requirements
ISO 9000
Set of international standards on quality management and quality assurance, critical to international business
Optimization
Setting up cost functions into mathematical formulas, then using a formal process to find the optimal values for the independent variables.
Ways to Model the Product to Evaluate Performance
Simulation and Prototypes
Factor of Safety
Strength of Material / Maximum Stress
Additive Tolerance Stack-Up
Takes the worst-case scenario of tolerances and adds them up
Physical
The actual object, or the model/prototype representing the object (Design Language)
Tolerances
The amount of variation that is allowable for the part to function in a high quality way; communicates information to manufacturing that is essential in helping to determine which manufacturing processes can or should be used and to establish quality control guidelines. Making these tighter to reduce variation usually induces increased costs.
Overhead Costs
The cost of doing business
Graphical
The drawing or CAD model of the object (Design Language)
Analytical
The equations, rules, or procedures representing the object (Design Language)
Product Definition
The goal of this is to understand the problem and lay the foundation for the remainder of a design project. Engineering Specifications are set.
Function
The logical flow of energy, material, or information between objects or the change of state of an object caused by one or more flows tells WHAT the function must do
Semantic
The verbal or textual representation of the object (Design Language)
Behavior
The way the product actually performs
Function
The way the product is intended to perform
Hannover Principles
These principles allow for the designer to design a product for sustainability
Inversion
Think of the opposite or inverse of what is needed to get an idea of what you need to do
Discover Design Products, Choose Design Projects, Plan design projects
Three major activities of the design process
Fault Tree Analysis (FTA)
To graphically develop a tree of all the faults that could happen to cause a system failure, and the logical relationships among these faults
Transition into a New Dimension(TRIZ)
Transition one dimensional movement or placement of objects into two dimensional, or two dimensional to three dimensional, etc
Product Manager
Ultimate responsibility for development of the product; link between product and customer
Proof-of-Concept prototype
Used for developing the function of the product to meet customer needs
Sketches
Used for idea generation
Quality Function Deployment (QFD) - House of Quality
Used to generate and evaluate good engineering specifications based on customer requirements and evaluating the success of competitor products. Ultimately helps determine what to design. Determines WHAT the customer desires
Proof of Process Prototype
Used to verify geometry and manufacturing process of the product, exact materials and processes are used to make the prototypes
Proof of Production prototypes
Used to verify the entire production process, usually generated by a "pre-production" run of the actual manufacturing process.
Trangulation
Using groups of three for stabilization of the form
Sources of Variation in Creating Part
Variation in machinery, machinery producing the part can only repeat to within a certain tolerance, and variation in raw materials
Project Risk
What can go wrong that will cause the project to fall behind schedule, go over budget, or not meet the engineering specifications
Robust Design
When something is designed to be as insensitive to noise as possible; "Determine values for the parameters based on easy to manufacture tolerances and default protection from aging and environmental effects so that best performance is achieved." Based on advanced statistical data collection and analysis, and is focused on reducing the variation in product performance ***identify which parameter most significantly affect product variation
Layout Drawings
Working drawing that supports the development of the major components of the system
Design Review
Written report that documents the choices made, lists the proposed next steps, and proposes a timeline and budget for next step
Risk
a function of uncertainty, an expected value, a probability that combines the likelihood of something happening multiplied by the consequences of it happening
patent
a government authority or license conferring a right or title for a set period, especially the sole right to exclude others from making, using, or selling an invention.
CNC Machining
a little robot thing with a special drill/drill bit that removes bits of material as a it moves
Performance
a measure of function and behavior
Sub-system
a small, discrete portion of the system
Degree of Freedom
ability to either move in one direction along a straight line axis (x, y, z) or to rotate around a straight line axis (roll, pitch, yaw)
trade study
activity of a multidisciplinary team to identify the most balanced technical solutions among a set of proposed viable solutions Goals: develop a series of cost functions, rate the proposed viable solutions using the cost functions to identify the best overall solution
patching
activity of changing a design without changing its level of abstraction
Mechanical failure
any change or any design or manufacturing error in the size, shape, or material properties of a component, assembly, or system that renders the product incapable of performing its intended function
Reliability Engineering
area of the design process that involves the testing predicting the expected failure rate; commonly measured by the mean time between failures (MTBF)
Product liability
branch of law dealing with alleged personal injury or damage to property or environment resulting from a product defect
Form Development
breaking down the final form into sub-systems or components
Design Build Test
building then testing physical prototypes
Random error
causes variation when the actual mean is close to the target value
bias error
causes variation when the actual mean is farther away from the target value.
Reversing (types of patching)
changing the component view often leads to more understanding
Form (structure)
conveys HOW a product will do something
Indirect Costs
costs that are necessary to run the business, but cannot be traced directly or exclusively to the specific component or product Includes overhead, marketing and selling expenses, profit, and discounts
Direct Costs
costs that can be traced directly to a specific component or product; includes materials, purchased components, tooling specific to a part, and labor costs, and some overhead costs
Variable Costs
costs that naturally fluctuate depending on the market
robust design
decisions that are as insensitive as possible to the uncertainty, incompleteness, and evolution of the information that they are based on; evaluated on belief map
Shape of Normal Distribution
depends on the values of the mean and the standard deviation Smaller standard deviation, more consistent and concentrated data values closer to the mean value.
Decomposing (types of patching)
divide a component into multiple subcomponents or assemblies
Segmentation (TRIZ)
divide an object into independent parts, make an object sectional, and increase the degree of an object's segmentation
deterministic models
each variable is represented by a single value
Quality Measures
engineering requirement targets identified in the house of quality and result in customer satisfaction
Diverging Flow
flow is divided into two or more bodies
Cost Function
function relating cost of production to level of output and other variables that the firm can control (check powerpoint)
Design Structure Matrix (DSM)
helps the design team identify functional dependence among various components in a product
Substituting (Types of Patching)
identify other concepts, components, or features that could replace the current idea
Assembly manager
in charge of putting all the subcomponents together and packaging the final product
Converging Flow
joining of multiple materials
Injection molding
like casting for plastics
Combining (types of patching)
make 1 component serve multiple functions or replace multiple components
manufacture
making the components
Through Flow
material is manipulated to change its position or shape
Composite Materials
material made of fibers and a matrix resin; has high strength and stiffness and good shear properties, its also low density
Reliability
measure of how the quality of a product is maintained over time
Rolling
metal is forced between giant rollers producing successively thinner sheets of rolling metal; often categorized by temperature
Reverse Engineering
method of dissecting a product to determine how it functions
stochastic
non-deterministic, variable parameter
Assembly
physical sub-system that must be joined to the main system
Vacuum forming
placing a sheet of heated plastic over a mold to form the shape
Gantt Charts
planning charts used to schedule resources and allocate time
Electrical failure
product does not function as expected because of an electrical problem, such as wiring coming loose or some component burning out
Software failure
product does not function because of a problem with the software
Design patents
protect the form or physical characteristics of the object
Utility patents
protect the function of a product
assembly
putting together the final product by combining and connecting the components
Rearranging (types of patching)
reconfiguring the components' positions or function
Permutations
reordering the functions to see what will happen
Simulations
require a detailed understanding of the system, requires the building of a high-fidelity model that predicts behavior accurately, much less expensive than physical prototypes.
Product Design Engineer
responsible for overall product design and ensures solution meets requirements
Forming
shaping of metal using localized compressive forces which are provided by a hammer or by a press Tend to be stronger than cast parts
Component
single part of an overall system
Turning (machining)
spinning a part about an axis, then having a blade press into the spinning object form its side.
SWOT analysis
strengths, weaknesses, opportunities, threats; Matrix for making project portfolio decisions
Configuration
the architecture, structure, or arrangement of the components and assemblies of components in the product
Product Decomposition (Reverse Engineering)
the careful disassembly of a product part-by-part to determine how it is made
Decision Risk
the chance that the choices made will not turn out as expected
Accuracy
the correctness or truth that the model is capable of predicting (high fidelity usually means high accuracy)
Original Design
the development of an entirely new product, process, or assembly
System
the entire product
Gross Wages
the portion of annual salary paid for this period or based on the number of hours worked multiplied by an hourly rate
executive summary
the section of a design report that provides the key information that will be included and documented in the rest of the report
Components
two subsystems connected by an interface
Failure
unsatisfactory behavior
Design Test Build
using mathematical/physical models to simulate product behavior
Noise Variation
variations due to the operating environment (including the operator and age of the product); a product is considered high quality if this has little effect on product performance