about Science and Engineering The National Electronics Museum

about Science and Engineering The National Electronics Museum October 26, 2016 Dan Zeitlin

Agenda q Science and Engineering What Scientists do What Engineers do Education Engineering Disciplines & Activities the Engineering Process Got Trouble? Build Knowledge & Skills q Soldering q q q q dbz 2016 STEM ED p - 2

Science and Engineering are all around us. What are they? q “Science is the understanding and explanation of how our world works ” q “Engineering is the practical application of science and math to solve problems” What is it that scientists and engineers actually do? . . . dbz 2016 STEM ED p - 3

What Do Scientists Do? “Curiosity has its own reason for existing. ” … Albert Einstein q Scientists perform Basic Research § Study the universe to understand the nature of things § Expand mankind’s knowledge base § Motivated by curiosity q Scientists perform Applied Research § Make basic knowledge useful q Scientists use Scientific Method in their studies § Hypothesize § Design and perform Experiment § Record data and make conclusion from the data (Engineers use similar processes) Science provides the basis for mankind’s continuing advancement dbz 2016 STEM ED p - 4

What Do Engineers Do? “I dream of things that never were, and ask why not? ” q … John F Kennedy Engineers solve problems § Existing and future ones q Engineers turn ideas into reality § Make inventions “real” § Motivated to create things q Engineers perform Applied Research § Aimed at specific practical outcomes § Built on Basic and Applied Research The application of engineering improves the overall quality of our lives dbz 2016 STEM ED p - 5

Science & Technology Education Science and Math are the basic tools of engineers & scientists q Science The sciences provide an understanding of the “system” we live in and the pieces that make it up. § Physics § Chemistry q Math defines is the how things are and behave. language It teaches of us logical structured thinking. and §science Algebra §engineering Geometry and Trigonometry § Calculus dbz 2016 STEM ED p - 6

Engineering Disciplines Engineers study and work in a myriad of disciplines SYSTEMS MECHANICAL CHEMICAL CERAMIC AND MATERIALS MARINE/ OCEAN INFORMATION TECHNOLOGY NUCLEAR AEROSPACE STRUCTURAL ELECTRIC POWER SOFTWARE METALLURGICAL MATERIAL GEOLOGICAL AND GEOPHYSICAL INDUSTRIAL AGRICULTURAL ELECTRICAL ENVIRONMENTAL COMPUTER SCIENCE MANUFACTURING CIVIL ROBOTIC SUSTAINABILITY COMMUNICATIONS BIO / BIOMEDICAL TRANSPORTATION TRAFFIC HYDRAULIC MINERAL/ MINING PETROLEUM ARCHITECTURAL HIGHWAY HUMAN FACTORS AUDIO . . . and often combine them dbz 2016 STEM ED p - 7

Engineering Activities Engineering work spans from concept to end user support q Research & Development (R&D) § Develop new and needed technologies q Design and Development § Flesh out ideas and figure how to make them real q Production § Plan how and produce “products” q Sales § Help people and enterprises find what they need q Support § Help solve user problems anywhere anytime q Logistics and Maintenance § Create and run support systems dbz 2016 STEM ED p - 8

the Engineering Process The design process is really a problem solution path q Study the problem § Define requirements and objectives q Conceive a solution path § Create a design concept and plan q Execute the plan § Perform detailed design of the gizmo or application q Refine the design § Breadboard, simulate, alpha code q Build and test a “final” version § Prototype, beta code q Deliver § Manufacture, release product dbz 2016 STEM ED p - 9

“Stuff Happens” “Anyone who has never made a mistake has never tried anything new”. . . Albert Einstein q Mistakes and failures happen § Normal in Engineering and Science § Remember – Engineering is problem solving q Minimize failures by using a logical Plan § When developing, building, or testing § Follow the plan q Failures are opportunities § Find mistaken thoughts or actions § Learn, fix, and move on – Correct your design, plan, or action accordingly “Failure is good as long as it doesn’t become a habit. ” . . . Michael Eisner dbz 2016 STEM ED p - 10

What’s wrong? Effective trouble-shooting is simply logical problem solving q Finding the cause Plan your attack § § Verify what’s OK Identify what’s not Follow a logical sequence Avoid “shotgunning” q May be multiple causes q Find the Root Cause § What kicked off the problem? q Include “It can’t be. . . ” § Consider ALL possibilities § New parts not always good dbz 2016 STEM ED p - 11

Build your skills and knowledge Hands-on experience is a valuable part of a STEM education q Hands-on STEM opportunities abound § § § § § Electronic kit building Robotics (Fests & Competitions) Remotely Piloted Vehicles (Sea. Perch) “Green” projects Audio-Visual technologies Amateur Radio (Clubs) Computers Software “Apps” Math programs and challenges Other STEM activities dbz 2016 STEM ED p - 12

? Questions? Soldering next. . . dbz 2016 STEM ED p - 13

Soldering in electrical circuits The National Electronics Museum October 26, 2016 Dan Zeitlin dbz 2016 STEM ED p - 14

Solder Joint Properties Soldering provides electrical conductivity and protection A Good Solder Joint q Makes electrical contact between conductors q Provides minor mechanical support § Not the main support q Encapsulates the joint § Prevents oxidation of the conductors (it’s gas tight) dbz 2016 STEM ED p - 15

Physics of Soldering creates a metallurgical bond between pieces q Heat is applied to metal* parts to be connected § Wires, terminals, board tracks q Solder is applied to the parts § Heated parts melt the solder, not the iron q Alloys form between the solder and metals § Alloys bond the metal parts to the solder q Joint must not be cooled quickly or be disturbed § Otherwise solder crystallizes, losing bond strength * Usually copper, tin, steel, or noble metal dbz 2016 STEM ED p - 16

Soldering Process It’s important to let the work pieces melt the solder q Attach work pieces to each other mechanically § Don’t rely on the solder for strength § Exceptions are light parts through or on circuit boards q Use flux core solder § Flux helps clean the interfaces § May leave residue – can be cleaned q Heat iron to appropriate temperature § 370ºC (700ºF) is common for electrical solders Clean the iron’s tip q Lightly wet the tip with a little solder q § Will fill small gaps and help heat transfer to the metals Sometimes flux is added separately by brush or droplets dbz 2016 STEM ED p - 17

Soldering Process (continued) It’s important to let the work pieces melt the solder q Place iron tip so it heats all parts to be soldered § Make parts just hot enough to melt solder § Do not overheat by dwelling too long q Touch solder to opposite side of joint § Allow parts to melt the solder § Feed solder until the joint is filled or covered § Avoid applying excess solder q Remove iron smoothly and quickly § As soon as solder has flowed around it q A good joint will be shiny and well-wetted § Solder shape will be concave rather than convex (ball-like) Sometimes flux is added separately by brush or droplets dbz 2016 STEM ED p - 18

Solder Joint Examples The good, the bad, and the ugly Good Joint Just right Almost Too much Just right Bad Joint • • Cold joints • Shiny • Volcano-like concave shape • Attached 100% to wires and pads too much solder not enough wetting OK Not great Dull Ball-like convex shape Lumpy Only Partial attachment dbz 2016 STEM ED p - 19

Soldering Summary Electronic parts are connected using solder Soldering Process q q q Solder bonds metal together Usually copper wire and copper pads or terminals Metal must be hot enough to melt solder to make it “stick” Always heat the metals and let them melt the solder Simply melting the solder alone makes a poor “cold joint” Soldering temperatures are around 700 degrees F! Be Careful Wear safety glasses. Solder and flux may sputter Only touch the soldering iron’s insulated handle Never set the iron down anywhere but in its holder Wires will get hot. Hold them with a tool or not at all. dbz 2016 STEM ED p - 20

Questions? dbz 2016 STEM ED p - 21