Principles of Engineering

Research

"Don't reinvent the wheel" What has already been done to solve the problem? How do existing products fall short in terms of the constraints? Examine many sources (print, electronic, experts in the field, etc.)

Fabrication in Manufacturing

Casting (metals, ceramics and some other materials) Molding (similar to casting; used for some plastics) Forming (forging, rolling, extruding, pressing, bending, shearing, compressing, drawing, and stamping) Separating (cutting and sawing, pulverizing, drilling, shaping, and planning) Joining (fastening, adhesive bonding, thermal joining, welding, soldering) Treating and Finishing (in treating, ceramics are "fired" and metals and some types of glass are tempered; methods of finishing are blasting, sanding, buffing, polishing, plating, coating, and grinding)

Material Properties

Chemical Properties (behavior on a molecular level) Bonding (ionic/covalent) Chemical reactions (acidity in batteries, corrosion, etc.)

Many decades-old engineering systems are being updated to incorporate modern principles that improve efficiency. Engineers must use newer technologies and better materials to develop a product superior to anything that currently exists. To redesign a complex product or system, engineers may work together to produce the next generation in efficiency. Discuss some of the benefits of collaboration between engineers.

Collaboration between engineers is beneficial because they can find solutions in a quicker and more efficient manner

Working Drawings

Complete plans for an engineered product Generally prepared before a prototype is produced "Drafting" is the process used to prepare working drawings

Systems Trends

Complexity (especially in digital electronics) Importance (more focus on things like GPS and less on things like USPS) Security (transportation industry, specifically airlines; businesses with ID badges) Speed (self-service checkouts, automated toll systems, etc.)

Drawing Tools and Standards

Computer-aided design (CAD) Always drawn/printed to scale (ratio of the object in reality is drawn/printed on paper in proportion to its actual size)

Electromagnetic Properties

Conductor, insulator, or semiconductor

What are some objects that lend themselves to being drawn as oblique drawings?

Cubes, houses, staircases

Design process

Define problem --> develop solution --> build and test <----> refine and complete

Research and Development ("R & D")

Defining Engineering Problems Identify Problem or Opportunity Define Project Constraints Research and Brainstorming Development and Prototyping Testing, Analysis, Optimization Evaluation and Presentation

The Workforce

Diversity needed (male/female, cultural, young/older)

Explain the three main steps in the implementation stage of engineering design.

Draw,

Implementation

Drawings and Models (usually done in CAD) Prototyping (prototype is first working model of a design) Rapid prototyping (machine works in conjunction with CAD software to produce a physical model or prototype; example is a 3D printer) Full-Scale Development Testing and evaluation Redesign and Next-Generation Prototyping (series of prototypes) Communication Solutions (reports, presentations)

List some common traits of effective systems engineers.

Educated, creative, cooperative, organized

What types of resources could be used to assist engineering managers in assuring the efficiency of a project?

Effective communication skills

Early engineers were present during ancient times

Egyptians built pyramids Romans used math to build Colosseum, aqueducts, and roads Chinese built the Great Wall

Great engineering achievements

Electrification (making electricity readily available) Transportation (automobiles, highways, airplanes, spacecraft) Water supply and distribution Electronics and communication (computers & the internet) Agriculture Air conditioning and refrigeration Medical imaging (x-rays, CAT scans, MRI's) Materials (alloys, Pyrex, fiberglass)

Systems Thinking

Elements of Systems Thinking Understanding the needs of stakeholders Developing creative solutions Considering how the system will perform in its life cycle Considering how the subsystems will affect one another Identifying tradeoffs (advantages and disadvantages) Managing risk (addressing what may go wrong) Assessing the impact of the overall system

Why do engineers often need to repeat steps as they design a solution?

Engineers often need to repeat steps because either something in their plan didn't go as expected or there was a more efficient way to resolve the problem

Calculus Applications

Exponents and Logarithms Differential Equations Derivatives

List three systems that are part of your school and three that are specific to a lab/classroom. Determine whether they are open-loop or closed-loop systems.

Faucets (open), fire alarms (both), lights (both)

The engineering design process has many steps, from the initial ideation stage that might involve sketching and simple drawings, to the production of a new or improved product that might require multiple technical drawings. Being able to make sketches and drawings, both 2D and 3D, of your ideas lets you share them with others throughout this process. Sketch 6 views of an object using standard multi-view orientation. After you have completed your sketches, describe which views are necessary to fully describe the object.

Front, back, top view, bottom view, face view

Earth Science Applications

Geology Water (fluid mechanics)

Shredded tires are used to provide a cushioned surface to reduce injuries to children on playgrounds. What might be some other uses for shredded tires?

I read somewhere that shredded tires can be made into pencils. They can also be used as soles of shoes, running tracks, aggressive confetti

How has technology affected the routines of many farmers?

In some cases, it has improved their jobs. It other cases, it can harm their jobs.

Identifying Stakeholders

Individual/group that has an interest in the project and can affect or be affected by its outcomes

Connecting Old and New

Infrastructure Technologies and compatibility

Algebraic Applications

Inverse functions (dimensional analysis) Quadratic functions y = ax2 +bx + c

System Engineering

Involves application of systems knowledge and systems thinking

Pictorial Drawings

Isometric drawings show one corner of an object drawn with two sides emerging from that corner at 30 degree angles from the horizontal Oblique drawings show a complete side of an object with only one side drawn, usually to the right and at a 45 degree angle Exploded view (or assembly type) is a variation of isometric or oblique style, usually made to show how component pieces of a device/system fit together Perspective is a type of pictorial drawing that shows an object in a realistic, 3D fashion Patent drawings have certain requirements

Manufacturing Properties

Machinability (ability to be worked to a surface finish or at certain speeds) Castability (how easily a material can be molded from liquid form)

Composite

Made from at least two distinct materials, which remain separate and distinct in an application where they are combined (fiberglass and carbon fiber)

Applying the Universal Systems Model

Manufacturing System: Automobile Assembly Plant (Input - The goal is to produce automobiles. Process - To assemble the parts and paint the vehicle. Output - An automobile. Feedback - Vehicle is inspected and tested before it is shipped to dealer; customers let dealer know if they are happy with purchase) Information System: Internet Hotel Reservation System Input - The goal is to keep hotel fully occupied and input is travel requests from potential customers Process - Data management Output - Reservations Feedback - Customers receive an emailed survey regarding their recent stay

Synthetic

Materials found not in nature (metal alloys, synthetic fibers, polymers and plastics)

Fabrication in Construction

Metals (steel and other alloys are common in large-scale applications; copper, tin and aluminum tend are often cost-prohibitive in large-scale) Concrete (advantages are durability, strength, fire-resistance, low-maintenance, and typically environmentally sound; disadvantages are limited workability once cured, heavy, and is difficult to repair and maintain) Other Construction Materials (natural materials, plastics, glass, alloys, composite materials) Green Building Materials (woods such as bamboo, organic architecture, recycled glass, etc.)

Physical Models

Mockups (physical representation of a product) Form Study Models (scale model of a design usually of better quality and materials than a mockup) Rapid Prototyping (development of models and prototypes by using CAD and 3D printing) Appearance Models (high quality and detail; used for promotion and demonstration) Prototypes (full-scale working version of an item)

What items around you were designed by engineers?

My laptop, the cars outside, roads, buildings, my phone

Understanding Types and Classification of Materials

Natural Synthetic Composite

Kinds of systems

Natural Systems (solar system, respiratory and other biological systems, ecosystems, etc.) Human-Made Systems (schools, government, etc.) Engineered Systems (traffic control, cable television, telephone, Internet, etc.)

Modern Engineering

Officially began during Renaissance (primarily used for military purposes) First formal institutions for preparing engineers were in France (1700's) Mechanical engineering began in England and Scotland with invention of steam engines and other machines used for textile industry Training became more formal after American Civil War

Open- and Closed-Loop Systems

Open-loop systems do not respond to changing conditions (clothes dryer) (infinite) Closed-loop systems can adjust for changing conditions (clothes dryer which senses how dry the clothes are... or AC because it shuts off when the house is cooled to the set temperature)

Theoretical Models

Optimization (types and amounts of materials, cost, time, etc.) Computer Simulations (animations) Mathematical Models (using parameters and variables to create formulas)

Documenting Your Work

Patents (intellectual property) Witness and Disclosure (both a legal and practical purpose for a project)

Basic Mathematics

Ratios (unit conversions; air-to-fuel, thrust-to-weight, and gear ratios) Reciprocals Logic and algorithms- Logic is the study of mathematical reasoning to solve a problem. Algorithms are step-by-step processes used to complete tasks Dimensions and units (accurate measurements; SI vs. English units) Statistics (probability - risk assessment and management, normal distribution and standard deviation)

Algorithm Symbols (using "getting ready for bed" as the flowchart/algorithm)

Rectangle represents a process (e.g., put on jammies, turn out light, etc.) Diamond represents a decision (e.g., do I want to read tonight?) Predefined processes is identified by a rectangle a vertical bar on each edge (e.g., taking a shower, brushing your teeth) Parallelogram represents data (e.g., time you fell asleep)

Optical Properties

Reflectivity Absorption Refraction (bending of light upon entering a new medium) Dispersion (separation of light wave into colors) Luminosity (brightness) Color

Acoustical Properties

Reverberation and absorption with noise control and medical applications

How do sketches help an engineer work out the details of an idea?

Sketches help an engineer work out the details of an idea because sometimes it is better to just draw things out than it is to use words

Brainstorming and Idea Development

Sketching (front, top, right, cross-sectional, or other) Alternative Solutions- Initial idea is not always the best Choosing the Best Solution- All viable ideas must be analyzed for their expected performance Functional Analysis- Determination of whether design will work as expected Decision Matrix- Mathematical tool intended to justify a solution. Used to narrow options and identify alternative solutions Tradeoffs- Is efficiency or appearance more important? Would a product sell if it cost more but used better quality materials?

Subsystems

Smaller system that is part of the larger system (for a flashlight, the battery, LED, reflector, lens, and on/off switch all serve as subsystems) Communication systems (internet, radio, newspapers/magazines) each require subsystems to complete the tasks involved in those systems

What sources of power are used to create electricity in your area?

Solar power, gas, water power

Engineering Problems and Opportunities

Solve specific problem or improve existing device/system

Strength of Materials

Stress - amount of force exerted in a certain area (F/A) Tensile strength - maximum stress that a material can withstand when subjected to tension (stretching) Compressive strength - material's ability to withstand compression Shear strength - atoms in a material are forced to slide past one another Deformation (strain) - change in a material's size/shape when under stress Deflection, yield strength, fatigue, elasticity, ductility, and malleability are all types of deformation

Structure

System of a flashlight has a structure of LED, power source, switch, lens, reflector, and circuit

Interconnectivity

Systems have boundaries, but an element in one system is often part of another

What engineered products do you find useful to your daily routine?

Technology, cars, roads, buildings

What is an event that can be analyzed or predicted using computer-generated animation?

The path of a hurricane

Analyze how the existence of older systems presents unique challenges for engineers developing new systems.

The systems have to work together, avoid patents to make sure your product is original

Thermal Properties

Thermal conductivity Metals expand when temperature increases Flammability Melting and boiling points

Patent drawings must meet the unique guidelines of the United States Patent and Trademark Office. What purpose do these standardized guidelines seve?

These guidelines tell the manufacturer what information the drawing needs to include and it keeps everything uniform

Why are exploded view drawings used for assembly instructions?

They are used for assembly instructions because they show how everything connects and forms the final product

What does a nuclear power plant have in common with power generation methods that use coal or oil?

They both generate power, produce waste

How many sides are visible in an isometric drawing?

Three

Design Constraints

Time, energy, space/area, tools, people, materials, capital, information, etc.

Discuss why engineers often develop two or more possible solutions to an engineering program in the early stages of development.

To have a backup plan, multiple solutions, one better solution than another

Dimensions and Tolerances

Tolerance is how much an actual measurement can vary from the design without affecting the product's performance

Orthographic Projection

Type of drawing that depicts objects in a two-dimensional way Generally uses three aligned view (front, top, and right)

Torque is dependent on three variables: the applied force, the length of the lever arm, and the angle between the force and the lever arm. What might you do to loosen a nut that you have not been able to loosen with a standard wrench?

Use a wrench with a longer arm

Natural

Wood from trees Most naturally occurring metals Fibers from plants

Physics concepts

Work, energy, and power (including kinetic and potential energy) Thermodynamics Forces and motion (kinematics, mechanics, and torque) Optics (study of behavior and properties of light) Acoustics (study of sound waves)

What is an engineer's goal when creating a sketch?

An engineer's goal when creating a sketch is to see how their idea looks when it's put together on paper

What is the difference between an invention and an innovation?

An invention is something new that has been created. An innovation is simply a concept that has not been created yet

Major Activities of Engineering

Analysis (important in beginning new projects) Research (search for new knowledge within a particular field) Design (development of formal plans for creating products and processes) Testing (including quality control) Development (building of prototypes, testing of results, and changes made) Management (supervision of a team of engineers working on a project) Consulting (individuals/companies who provide expert advice/assistance) Sales (persuading clients to purchase product or service)

Science, technology, and math form the core of engineering

Analysis, research, design, testing, development, management, consulting, and sales are involved in the engineering process

Other Design Factors

Appearance, durability, flexibility, simplicity, safety

Geometry and Trigonometry Applications

Area and Volume Vectors Trigonometry (whenever triangles are used)

What are some non-medical uses for x-rays?

Art, lasers

Chemistry Concepts

Atomic and Molecular structure Materials Science (polymers/plastics) Organic Chemistry (hydrocarbons, specifically propane and octane) Electrochemistry (batteries) Environmental Chemistry (water treatment, hazardous waste management)

The study of biomechanics has enabled engineers to develop functional artificial limbs for people and animals. What is the focus of the work of biomedical engineers?

Biomedical engineers apply engineering to healthcare and biology

Biological Applications

Botany Genetics, Anatomy, and Physiology (biomedical engineers; genetics/heredity) Bioremediation (use of microorganisms to clean environment)

Name some places in your home or town where parabolic shapes are used in designs.

Bridges, fountains, arches, McDonald's arches

System Outputs

Can be expected, unexpected, desirable, or undesirable Ex: Automobiles produce exhaust (expected but undesirable) Ex: Automobiles run (expected and desirable) Ex: Automobiles can fly (unexpected but desirable) Ex: Automobiles break down (unexpected and undesirable)

Universal Systems Model

Can describe how any system works (large or small, simple or complex) All systems have a common set of elements- Input - what you want the system to do (the need) and resources that are put into the system Process - action part of the system where resources interact and are combined Output - result of the system once the process has been completed Feedback - information about the input, process, or output, which is used to adjust the system