E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Science as Inquiry: As a result of activities in grades 5-8, all students should develop • Understanding about scientific inquiry. • Abilities necessary to do scientific inquiry: identify questions, design an investigation, collect and interpret data, use evidence, think critically, analyze and predict, communicate, and use mathematics. Source: National Science Education Standards NSES Standards for Grades 5-8: Science and Technology •Technology influences society through its products and processes. Technology influences the quality of life and the ways people act and interact. Technology changes are often accompanied by social, political, and economic changes that can be beneficial or detrimental to individuals and to society. Social needs, attitudes, and values influence the direction of technological development. •Science and technology have advanced through contributions of many different people in different cultures, at different times in history. Science and technology have contributed enormously to economic growth and productivity among societies and groups within societies. •Scientists and engineers work in many different settings, including colleges and universities, businesses and industries, specific research institutes, and government agencies. ISTE Standards: Critical thinking, problem solving and decision making. Students: •Identify and define authentic problems and significant questions for investigation. •Plan and manage activities to develop a solution or complete a project. •Collect and analyze data to identify solutions and/or make informed decisions. AAAS (2061) Benchmarks for Grades 3-5 and 6-8: •Clear communication is an essential part of doing science. It enables scientists to inform others about their work, expose their ideas to criticism by other scientists, and stay informed about scientific discoveries around the world. •No matter who does science and mathematics or invents things, or when or where they do it, the knowledge and technology that result can eventually become available to everyone in the world. •Systems fail because they have faulty or poorly matched parts, are used in ways that exceed what was intended by the design, or were poorly designed to begin with. NCTM Expectations: •Solve problems that arise in mathematics and in other contexts. •Apply and adapt a variety of appropriate strategies to solve problems. •Develop fluency in adding, subtracting, multiplying, and dividing whole numbers. •Select appropriate methods and tools for computing with fractions and decimals from among mental computation estimation, calculators, and paper and pencil according to the context and nature of the computation and use the selected method or tools. •Factors such as cost, safety, appearance, environmental impact, and what will happen if the solution fails must be considered in technological design. •Scientific laws, engineering principles, properties of materials, and construction techniques must be taken into account in designing engineering solutions to problems. •Models are very useful for communicating ideas about objects, events, and processes. When using a model to communicate about something, it is important to keep in mind how it is different from the thing being modeled. •Different models can be used to represent the same thing. What model to use depends on its purpose. •Use multiple processes and diverse perspectives to explore alternative solutions. NETS for Teachers: Teachers promote student reflection using collaborative tools to reveal and clarify students’ conceptual understanding and thinking, planning, and creative processes. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 1 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Science Process Skills: • • • • • • • Observing Comparing Inferring Predicting Communicating Designing Constructing Math Process Skills: • Analyzing • Comparing • Computing Objective: The learner will recognize the engineering design process is a method of problem solving used to create a system, a product, or a process that meets an identified need. Time: 40–60 Minutes Materials: • Launch Apparatus: 15–20 feet of string or fishing line, cinder block or brick, one roll of duct tape, large trash bag or tarp. • 2 wire hangers • Ladder • Eggbert Glider (this can be either the manufactured glider or wooden glider) • Eggbert Seats (1 per team) (1” × 2” piece of pine, drill, hammer, nails, glue) • Eggs (1 per team) • Materials for students to purchase for designing restraint system: Plastic bags, rubber bands, string, cotton balls, clay, foam pads, toilet paper, masking tape. • Student booklet • Pencil • Markers E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 2 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Instructor Preparation : Eggbert Activity Make the glider and seats. This can be either the manufactured glider or a wooden glider. Set up the launcher apparatus by tying the glide path line to the ceiling and the top of the cinder block or brick. Place the block on the floor across the room so that the line descends at approximately a 45° angle. Put plastic tarp or large trash bag under and around the block. Prepare materials for each group to purchase when designing the restraint system. You might want to put materials in bags for each team so they can decide what to purchase. Or, you may choose to set up a store where teams can purchase materials. Have eggs available for distribution. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 3 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Instructor Background Information: Key Vocabulary Inertia—the tendency of an object to resist a change in motion. An object at rest, will remain at rest unless a force acts on it. An object in motion, will continue in the same direction at the same speed, unless an outside force acts on it. Newton’s First Law of Motion deals with inertia. Momentum—the product of an object’s mass and velocity, which determines how difficult it is to stop the object’s motion. What Is the Engineering Design Process? The Engineering Design Process is a series of steps that aid in the design of an effective solution for a given problem. Engineers use different versions of the steps. Here is one example of the steps of the process: • Define • Research • Develop • Choose • Create • Test and Evaluate • Communicate • Redesign Define the Problem Force—a push or a pull that gives energy to an object, sometimes causing a change in the motion of the object. Engineering Design Process—a cyclical method of problem solving used to create a system, a product, or a process that meets an identified need. Potential Energy—energy that is stored within an object, not in motion but capable of becoming active. 2 8 Acceleration—a change in velocity (speeding up or slowing down). Research Redesign the Problem 3 7 Communicate Develop Possible Solutions 1. 2. 3. 4. 5. Option One O p t i o n Tw o Option Three Option Four Option Five 6 4 Test & Evaluate Choose the Best Solution 5 Create Kinetic Energy—energy in motion. a Prototype E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 4 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Define: The Engineering Design Process always begins with a need, or a problem that must be solved. It may also involve an improvement to an existing design. The main challenge at this point is to define exactly what the need is, including any specific requirements. A complete understanding of the need will make the solution easier to design. Research: Once a need has been established, the next step is to ask questions about the nature of the problem and to do any necessary background research. Other people may have tried to solve a similar problem in the past. Engineers may incorporate past work into their own design process, but they must be careful to not use someone else’s idea without permission. Develop: This is essentially the brainstorming phase of the process, which gives engineers a chance to be creative. It’s important to remember that there may be more than one solution to a problem, and, in many cases, there are multiple solutions. Once a list of ideas has been generated, the engineers can select the most promising idea to work on. Choose: Planning involves taking an idea and filling in all the details that will bring the idea to life. While developing the idea, engineers will break the design into smaller parts to determine exactly how each part will function, draw diagrams, and compile a list of necessary materials. As they develop their solutions, engineers often call on their own knowledge of math and science, but they may have to do additional research to complete their design. Create: After the planning stage is complete, engineers build a prototype of their design, then come up with effective ways to test it. Test and Evaluate: Once the design has been tested, they use the results as a basis for possible improvements. Engineers examine what worked, what didn’t work, and what could work better. Communicate: In this stage, engineers use this data from their tests to make improvements on their design. This is also a good time for peer review and feedback. Redesign: Upon receiving feedback, engineers may make further improvements on their design until they are satisfied with the final version. The process seems linear, but in practice, the steps may blend into each other, occur out of order, or repeat several times. Engineering is the process of trying, creating, testing, and then re-trying until the design works. It can be a lengthy and drawn-out process, and it is rare that a design works perfectly the first time. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 5 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Vehicle Restraint Systems For this activity, students will be designing restraint systems to keep Eggbert from cracking. These systems may (or may not!) be similar to some of the current restraint systems that are commonly used in modern vehicles, such as airbags, seat belts, and harnesses. Airbag = passive restraint system Seat belt = active restraint system Airbags are known as a “passive restraint” system, which may sound confusing since most people do not think of airbag deployment as a “passive” event. They are designated as “passive” because airbag deployment requires no action on the part of the user. Airbags will deploy automatically in the event of a collision that meets a pre-programmed set of specifications (speed, deceleration, angle of impact). Many modern cars contain front and side airbags for both the driver and front passenger of the vehicle. Airbags were originally designed as an alternative to seat belts, but in reality, they do not provide the same protection. In a collision, the airbag can cause as much injury as other parts of the car to those who do not wear seat belts. Airbags deploy and deflate faster than the blink of an eye (about 1/20 of a second). Occupants should always wear seat belts, and drivers should sit at a reasonable distance from the steering wheel. Some modern airbags have sensors that detect the size and weight of an occupant and adjust the force of the airbag deployment accordingly. However, many vehicle manufacturers recommend that small occupants, such as children, remain in the back seat. Seat belts, the primary restraint system in most vehicles, are still regarded as the most effective form of restraint. Unlike airbags, seat belts are “active restraint” systems, because they require the user to actively attach the seatbelt before driving. There are three main types of seat belts in modern cars: • lap belts • shoulder belts • three-point belts Three-point belts combine the best features of lap and shoulder belts, and they are generally considered the safest form of restraint, because they hold the occupant securely in the seat and, in the event of a collision, evenly distribute the force between the occupant’s chest and hips. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 6 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Many seat belts also have additional features to increase safety. A common feature is the inertial lock, which automatically locks the seat belt if it is jerked forward quickly (as in a crash). Another feature (designed for forgetful drivers) is the automatic seatbelt. In most of these cases, the occupant is still required to manually put on the lap belt, but the shoulder belt will move along a track and fasten into place once the car is turned on. Some variations on the seat belt include the five-point belt, which is usually used in infant car seats, and the six- and sevenpoint belts, which are often used by race car drivers. Other variations can be found in vehicles other than cars. Planes, for example, still use only lap belts for their passengers. Roller coasters usually use either over-the-shoulder restraints (for inverted rides), or lap bars, which are designed to be loose restraints so as to increase the sense of “danger.” E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 7 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Lesson Mission Eggbert has volunteered for the first egg-head mission to the Moon. The dilemma Eggbert faces is that the landing on the Moon’s surface will be very quick, and the glider will crash. To ensure the success of this mission, your engineering team will need to design a safety restraint device that will withstand the crash. Note: Explain to the students that in real life, cost is a factor that engineers must take into account as they work on solutions. For this activity, they must restrain Eggbert using only limited supplies in their budget. Your team has a budget of $800.00 to spend on the materials for the design. Each item has a limit (x) and a cost. You must discuss what materials you will purchase, keeping within your budget, and record the items in a spreadsheet. You must also ALL agree on a team design. If Eggbert does not survive your first attempt, you may have time to redesign the restraint system. You might want to consider saving some money for a redesign. Happy Designing! Introduction: Engineering Design Process Strategic Questions: What does an engineer do? What steps does an engineer take to solve a problem? Lead students to define an engineer as someone who solves problems by developing new or improving existing products or ways of doing things. Someone who solves problems for a living must have a problem-solving method. Engineers have followed the same basic method or process for thousands of years. The process is: a. Define the problem b. Research the problem c. Develop possible solutions d. Choose the best solution e. Create a prototype f. Test and evaluate the prototype g. Communicate results h. Redesign if necessary * Go through process again (Repeat) E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 8 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Walk students through an example of engineering a product —such as a toothbrush—so they can understand the steps in action. PTC software designed the Braun toothbrush. Define the problem: People need to have a device to apply toothpaste to their teeth to remove plaque and germs. Research the problem: Look up what other people use, study other toothbrushes, study plaque accumulation on teeth, etc. Develop possible solutions: Brainstorm everything you can think of related to brushing teeth; every bristle configuration, construction material, length, width, etc. Choose the best solution: Out of all the ideas, choose one or a combination of several that you think would work the best. Create a prototype: Make a model of the design you have chosen. Test and Evaluate: Use the model and complete several tests. Use the model several times and assess the results. What worked well and what needs improvement? Communicate: Discuss the results with others and brainstorm solutions to problems and possible improvements. Perhaps the tests showed that your back teeth were not getting clean enough, but it was difficult to position your hand in a way that the toothbrush could reach those teeth adequately. You decide to bend the handle of the toothbrush to angle it to reach your back teeth better. Redesign: You decide to start the process all over again to make a new prototype with the angled handle. *Define the problem: Now you have a new problem: How do I angle the toothbrush to get maximum cleaning of the back teeth? The process continues. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 9 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Note: As students discuss various kinds of seat restraints, encourage them to think about how the restraints they have seen are different. Have them consider why a restraint might have been designed a certain way. Explain that the Department of Defense has hundreds of engineers working on devices to make military equipment safer. The students will apply their knowledge of the engineering design process to design a safety restraint device for Eggbert’s glider, just like a DoD engineer would do. Have students discuss their prior knowledge of seat restraints, whether in cars, planes, amusement park rides, or child seats. Remind them that this knowledge may be useful to them as they complete their designs. The Design Process Steps A through E Strategic Questions: What forces can you identify that will be in operation and will act on the glider? (potential energy, kinetic energy, gravity, friction, the cinder block) What forces can you identify that will be in operation and will act on Eggbert? (potential energy, kinetic energy, gravity, friction, the cinder block, and the restraint system if designed properly) Introduce students to Eggbert and display his glider and seat. Demonstrate how the glider will be traveling and crashing, where the seat will be located, and how the seat attaches to the glider. Pass out an egg, a seat, and a bag of materials to each group of four students (or have students purchase from store after design is completed). Give the groups 5 to 10 minutes to discuss their design plans, working through Steps A to E in the Engineering Design Process. Students must also write their purchases in the spreadsheet. After groups decide on prototype designs, allow them several minutes (determined by your number of groups and schedule) to construct their restraint systems. Remind them that, time permitting, it may be necessary to redesign. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 10 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Items: Plastic bag (2) $120.99 ea. Rubber band (2) $99.35 ea. String (3) $49.12 ea. Cotton ball (2) $101.26 ea. Clay (1) $98.98 ea. Foam (1) $96.03 ea. Square of toilet paper (3) $48.05 ea. Sample spreadsheet: Item Cost Quantity Total Every team gets one free 30-cm piece of masking tape E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 11 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert The Design Process Steps F through H Test each crew’s system by sending the glider down the wire. Check for understanding by discussing the results of each landing. 4 Check for Understanding: Which restraint systems were successful in protecting Eggbert from injury? Which systems were not? Why or why not? Have students discuss possible improvements to their designs. 4 Check for Understanding: What is the next step in the Engineering Design Process? (redesign) How can the unsuccessful design be altered to ensure Eggbert’s safety? (answers will vary) How can the successful designs be improved? (make more comfortable, make design more appealing, use fewer materials to reduce cost, etc.) After the discussion and debrief, challenge the design team to redesign the prototype to get better results. Distribute achievement certificates to the groups that were able to successfully keep the egg from breaking. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 12 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Suggested Final Assessment Questions Apply knowledge 1. Why are airbags not meant to replace seat belts? Possible answer: Air bags are dangerous. If a person in a crash wasn’t wearing a seat belt, inertia would cause the person to fly into the airbag, which could cause injury. Evaluate 2. Imagine you are designing a restraint system for a real person (not an egg). What are additional factors that you would have to consider? Possible answer: The restrained person would still have to have some freedom of movement. Analyze information 3. Why is it important to plan a design carefully before you build it? Possible answer: If you build without planning, the design is more likely to have problems. Planning first can save time and money. Knowledge Application 4. A car manufacturer designs, builds, and sells a car model. What step of the design process has the manufacturer forgotten? Why is this step important? Possible answer: The manufacturer forgot to test the car model. Without testing, there is no way to know if the car will work properly, or if it is safe. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 13 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Suggested Final Assessment Questions 1. Why are airbags not meant to replace seat belts? 2. Imagine you are designing a restraint system for a real person (not an egg). What are additional factors that you would have to consider? 3. Why is it important to plan a design carefully before you build it? 4. A car manufacturer designs, builds, and sells a car model. What step of the design process has the manufacturer forgotten? Why is this step important? E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 14 Eggbert Activity Assessment Activity Log 1. Sketch and label the parts of your team’s design. 2. How well did your design work? Circle the condition of Eggbert after launch. Survival (no damage) Living…with cracked skull (shell cracked) Unconscious with brain damage (yolk broke) Totally scrambled (everything is broken) 3. How could your group modify your design to make it better? 4. How did your group work as a team? What was the most difficult part? Eggbert Activity Answer Key This space should contain a drawing of the group’s seat design, including labels of the parts where appropriate. 2. How well did your design work? Circle the condition of Eggbert after launch. Survival (no damage) Living…with cracked skull (shell cracked) Unconscious with brain damage (yolk broke) Totally scrambled (everything is broken) Students should circle the relevant condition of the egg after their first launch. 3. How could your group improve or modify your design? 1. Sketch and label the parts of your team’s design. Activity Log Students should include suggestions of modifications they could make to their design. 4. How did your group work as a team? What was the most difficult part? Students should include comments evaluating their work as a team. The answer should include what they thought was the most difficult part. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Making the Manufactured Glider To make the glider 1.Individually load the four STL files for the Eggbert Glider (GliderFuselage, GliderNose, GliderSeat, and GliderTail) in the Catalyst software. 2.Make certain to set the layer Resolution to 0.010 and the Printer Interior Style to Solid-Normal. 3.Orient the model onto the base. 4.Print the models. Making the Wooden Glider To make the glider 1.To construct Eggbert’s glider, begin by photocopying the Eggbert glider template. 2.Cut out the patterns, arrange them on the 12” x 13” pinewood board, and trace their outlines. When arranging the “Base” and “Nose (Part A)” patterns, align the pieces by putting them together at the dashed lines. 3.With a jigsaw, cut the patterns from the board. 4.To attach part B of the nose, apply glue to one side of part B and match it up with part A of the nose. (You can use either side of the glider’s base, but whatever side you select, this will be the topside of the lander.) Strengthen the fit by driving two nails through parts A and B of the nose. (Again, to prevent wood splits, it is worth taking the time to drill the holes for the nails first.) 5.Smear glue along the bottom edge of the tail and align it along the center of the base. Reinforce the attachment by driving two nails from the underside of the base into the tail. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 17 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert 6.Check the fit of the seat assembly between the tail and part B of the nose section. If the fit is too tight, shorten the seat base by sanding or cutting its front edge. Once you establish a good fit, mark the location of the hole for the bolt onto the glider’s base. Drill a hole through the base of the glider with the same bit used to drill the hole through the seat. 7.Cut two 6-inch lengths from the wire coat hanger. Fashion a hook-like loop on one end of each wire and bend the hook to a 90-degree angle. (The #12 x 1” wood screw will fix the wire to the underside of the glider’s base. The loop, therefore, should be large enough to accommodate the screw’s shaft but, at the same time, small enough to keep the head of the screw from slipping through.) 8.Drill two narrow holes for these wires. Drill the first through the tail and glider base, and the second through parts A and B of the nose. 9.Entering from the underside of the base, slip the wires through the holes. Anchor the wires to the base using the #12 x 1” wood screws. 10. Twist the top of the hanger wires into a loop as shown on page 22. This will prevent the glider from skipping off the fishing line at impact. You can easily make the twist using a pair of regular or needle-nose pliers. 11. As a bumper to preserve the longevity of the glider, glue or nail the plastic strip along the front edge of the nose. 12. Slip the 5/16” x 2” bolt through the hole in the seat base. Apply a generous amount of wood glue over the head of the bolt and allow it to dry thoroughly before use. 13. To improve the attractiveness of the glider, you may elect to paint or decorate it. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 18 E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert To make the seats 1.Use the templates to cut two pieces from the 1” × 2” pine wood. The base of the seat should be significantly longer than the back. 2.Glue the end of the base to the bottom edge of the back, forming a seat. Hammer nails through the other side of the back to secure the base. 3.Drill a large hole 1” from the far edge of the base. This should correspond to the large hole you drilled in the main glider piece. 4. To attach the chair to the glider, insert a bolt through the large holes in the seat and base (the two holes should line up), and secure it from the other side with a wing nut. Each individual seat can be attached and removed from the glider this way. 5.Make enough seats for each group in the class to have one. 6.Set up the launcher apparatus. Use a ladder to tie the upper end of the glide path line (string or fishing line) high enough so that the line runs at about a 45° angle down to the cinder block on the floor. The length of the string should be about 15 to 20 feet, so the upper end should be tied between 10 and 14 feet off the floor. Modify height as needed for lower ceilings. 7.Set up a large trash bag or two under the cinder block, as this activity may become messy. 8.Prepare a complete set of supplies for each group to use to use in its restraint system. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 19 Glue 1/4” aluminum rod cut to 22-mm length EGGBERT‛S GLIDER Insert seat into slot and push forward to lock into place Glue nose onto fuselage Good Luck! Glue tail onto fuselage Develop a hanging system of your own. These holes are designed to accept a #8 eye bolt. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 20 Base (Part B) Nose (Part A) Nose EGGBERT‛S GLIDER (wooden version) Tail apply glue to underside and nail base to tail drill hole through tail and glider base for wire anchor wire loop with screw drill holes for bolt 6” length of clothes hanger wire form a loop on the wire hanger affix to nose apply glue to underside and nail to nose drill hole through nose for wire EGGBERT‛S GLIDER (wooden version) nail seat back to base bend loop to 90° angle and anchor to base with screw drill hole 1.5” from edge E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 22 Eggbert Certificate Helped save Eggbert by using the Engineering Design Process. The team designed a restraint system within budget that allowed Eggbert to land safely. Eggbert Certificate Helped save Eggbert by using the Engineering Design Process. The team designed a restraint system within budget that allowed Eggbert to land safely. E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) Activity: Eggbert Resources Sources: Eggbert is copyrighted by Melko, 1989. http://www.iihs.org/research/qanda/airbags.html http://www.nhtsa.dot.gov/people/injury/airbags/airbags03/page3.html http://auto.howstuffworks.com/seatbelt.htm http://inventors.about.com/library/inventors/bl_seat_belts.htm http://www.nationmaster.com/encyclopedia/Automatic-seat-belt http://science.howstuffworks.com/roller-coaster9.htm http://www.ptc.com E 3.1.1.4 Engineering: A. Engineering Design Process (EDP) 24