Lesson Plan Course Title: Engineering Mathematics Session Title: Mechanical Systems Performance Objective: At the end of this lesson, the students will learn about mechanical systems. They will learn about the most common used mechanical systems and how to calculate the mechanical advantage of the lever simple machine. Specific Objectives: Students will be able to understand the meaning of mechanical systems, identify the different types of mechanical systems, understand the mechanical advantage of the lever simple machine, understand the careers and educational opportunities available in the mechanical systems industry, and complete a mechanical advantage team project. Preparation TEKS Correlations: This lesson, as published, correlates to the following TEKS. Any changes/alterations to the activities may result in the elimination of any or all of the TEKS listed. Engineering Mathematics: 130.367 (c) (9) (A) (D) (E) (G) (H) . . .calculate the weight of an object for a given mass; . . .calculate the mechanical advantage of first-, second-, and third-class levers; . . .compare and contrast the advantages and disadvantages of the three classes of levers for different applications; . . .analyze and calculate mechanical advantage for simple machines using proper units of measurement; and . .. calculate the mechanical advantage of gear drive systems. Interdisciplinary Correlations: English: 110.44 (b) (6) (A) (B) . . .expand vocabulary through wide reading, listening and discussing; and . . .rely on context to determine meanings of words and phrases such as figurative language, connotation and denotation of words, analogies, idioms, and technical vocabulary. 110.44 (b) (7) (H) . . .use study strategies such as note taking, outlining, and using study-guide questions to Copyright © Texas Education Agency, 2012. All rights reserved. 1 better understand texts; Mathematical Models with Applications: 111.36 (c) (M.1) (A) (B) (C) . . .compare and analyze various methods for solving a real-life problem; . . .select a method to solve a problem, defend the method, and justify the reasonableness of the results. Physics: 112.39 (c) (2) (B) (C) (D) (E) . . .know that scientific hypotheses are tentative and testable statements that must be capable of being supported or not supported by observational evidence. Hypotheses of durable explanatory power which have been tested over a wide variety of conditions are incorporated into theories; . . .know that scientific theories are based on natural and physical phenomena and are capable of being tested by multiple independent researchers. Unlike hypotheses, scientific theories are well-established and highly-reliable explanations, but may be subject to change as new areas of science and new technologies are developed; . . .distinguish between scientific hypotheses and scientific theories; and . . .design and implement investigative procedures, including making observations, asking well-defined questions, formulating testable hypotheses, identifying variables, selecting appropriate equipment and technology, and evaluating numerical answers for reasonableness. 112.39 (c) (3) (A) . . .in all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, including examining all sides of scientific evidence of those scientific explanations, so as to encourage critical thinking by the student. Mathematics: calculation of mechanical advantage Liberal Arts: effective communication Copyright © Texas Education Agency, 2012. All rights reserved. 2 Occupational Correlation: (reference: O*Net – www.onetonline.org) 17-2141.00 - Mechanical Engineers Sample job description: Design and perform engineering duties in planning and designing tools, engines, machines, and other mechanically functioning equipment. Oversee installation, operation, maintenance, and repair of equipment such as centralized heat, gas, water, and steam systems. Sample of reported job titles: Engineer, Product Engineer, Mechanical Design Engineer, Process Engineer, Equipment Engineer, Design Maintenance Engineer, Systems Engineer, Chassis Systems Engineer, Commissioning Engineer Tasks: Read and interpret blueprints, technical drawings, schematics, or computer-generated reports. Assist drafters in developing the structural design of products using drafting tools or computer-assisted design (CAD) or drafting equipment and software. Research, design, evaluate, install, operate, and maintain mechanical products, equipment, systems and processes to meet requirements, applying knowledge of engineering principles. Confer with engineers or other personnel to implement operating procedures, resolve system malfunctions, or provide technical information. Recommend design modifications to eliminate machine or system malfunctions. Conduct research that tests or analyzes the feasibility, design, operation, or performance of equipment, components, or systems. Investigate equipment failures and difficulties to diagnose faulty operation, and to make recommendations to maintenance crew. Develop and test models of alternate designs and processing methods to assess feasibility, operating condition effects, possible new applications and necessity of modification. Develop, coordinate, or monitor all aspects of production, including selection of manufacturing methods, fabrication, or operation of product designs. Specify system components or direct modification of products to ensure conformance with engineering design and performance specifications. Soft Skills: Complex Problem Solving, Critical Thinking, Active Listening, Judgment and Decision Making, Reading Comprehension, Science, Operations Analysis, Active Learning, Speaking Copyright © Texas Education Agency, 2012. All rights reserved. 3 Teacher Preparation: Understand that students need to be creative with this lesson. Allow student teams to complete the contract spreadsheet and assign roles. Review the Microsoft PowerPoint and the Mechanical Systems Project. Provide student teams with handouts and materials. References: Slides 16-17 Levers – W&N created Slides 20, 26 First class lever – W&N created Slide 21, 27 Second class lever – W&N created Slide 22, 28 Third class lever – W&N created Slide 24 Mechanical Advantage video – http://www.youtube.com/watch?v=yfAdmRJDKIc; Science Online Slide 30 Linkages – http://commons.wikimedia.org/wiki/File:2008-04-24_Windshield_wiper_parts.jpg Slide 31 Cams – http://commons.wikimedia.org/wiki/File:Nockenwelle_2005.jpg Slide 32 Turnbuckles – http://commons.wikimedia.org/wiki/File:Turnbuckle.jpg Slide 33 Pulleys – http://commons.wikimedia.org/wiki/File:Polispasto2B.jpg Slide 34 Gears – http://commons.wikimedia.org/wiki/File:Gears_and_Stuff.png Slide 35 Key fasteners – http://commons.wikimedia.org/wiki/File:Hook_and_eye_clasp.JPG Slide 36 V-belt drives – http://commons.wikimedia.org/wiki/File:Keilriemen-V-Belt.png Slide 37 Chain drives – http://commons.wikimedia.org/wiki/File:Chain.gif Copyright © Texas Education Agency, 2012. All rights reserved. 4 Instructional Aids: 1. Mechanical Systems PowerPoint presentation 2. Mechanical Systems Project handout Materials Needed: 1. Engineering Notebook 2. Team Contract Spreadsheet 3. Calculators 4. Pen and Pencil Simple Machine Challenge: 1. Cardboard or cereal boxes 2. Soup cans or soda cans 3. Juice or sport drink lids 4. Various pieces of wood 5. Paint stirrers 6. Drinking straws 7. Dowel rods 8. String 9. Scotch tape 10. Duct tape 11. Glue 12. Modeling clay 13. Rulers 14. Measuring tape (cloth tape measure or tailor’s tape works best) 15. Other materials (to be determined by each student team) Lever and Pulley Challenge: 1. Cardboard or cereal boxes 2. Soup cans or soda cans 3. Juice or sport drink lids 4. Various pieces of wood 5. Paint stirrers 6. String 7. Scotch tape 8. Duct tape 9. Glue 10. Rulers 11. Measuring tape (cloth tape measure or tailor’s tape works best) 12. Other materials (to be determined by each student team) Mathematical Principles Challenge: 1. Newton spring scale 2. Mechanical systems/simple machines (levers, linkages, cams, turnbuckles, pulleys, gears, key fasteners, v-belt drives, chain drives) 3. Other materials (to be determined by each student team) Copyright © Texas Education Agency, 2012. All rights reserved. 5 Equipment Needed: 1. Computer 2. Overhead Projector Learner Preparation: None required Introduction Introduction (LSI Quadrant I): SAY: In this lesson, you are going to learn about the most common used Mechanical Systems, design these systems, and learn how to calculate the Mechanical Advantage for each of these systems. ASK: What are Mechanical Systems? SHOW: Mechanical Systems PowerPoint presentation. Outline Outline (LSI Quadrant II): Instructors can use the PowerPoint presentation, slides, handouts, and note pages in conjunction with the following outline. Class Period(s) Topic(s) • • • 1-2 Assignment Introduction Vocabulary Mechanical Engineering O*Net #1-Individual Write a one-page paper about the Mechanical Engineering Occupation. 3-10 • Simple Machines #2-In teams of 2-3, complete the Simple Machines Challenge. 11-15 • Levers and Pulleys #3-In teams of 2-3, complete the Lever and Pulley Challenge. 16-20 • Mathematical Principles Challenge #4-In teams of 2-3, complete the Mathematical Principles Challenge. MI Outline Notes to Instructor Introduction – 45 minutes & O*Net (www.onetonline.org) PPT presentation – 1 days (45 minutes) What are Mechanical Systems? Copyright © Texas Education Agency, 2012. All rights reserved. 6 Types of Mechanical Systems Careers and Educational Opportunities Mechanical Systems Projects Activities – 19 days (45 minutes) Team Contract Team Projects Team Presentations I. Mechanical Systems Introduction A. Information B. Schedule C. Introduction/Course Description D. Objectives and Results E. Vocabulary F. O*Net (www.onetonline.org) Slides 1-10 II. Simple Machines Challenge A. Lever B. Wheel and Axle C. Pulley D. Inclined Plane E. Wedge F. Screw Slides 11-13 III. Mechanical Advantage of Simple Machines G. First class levers H. Second class levers I. Third class levers J. Mechanical advantage of levers Slides 14-29 IV. Mechanical Systems and Mathematical Principles Challenge Slides 30-38 Assignment: Students write a one-page essay on the mechanical engineering profession. Assignment: Students will complete the Simple Machines Challenge. Assignment: Students will complete the Lever and Pulley Challenge. Copyright © Texas Education Agency, 2012. All rights reserved. 7 A. B. C. D. E. F. G. H. Verbal Linguistic Logical Mathematical Assignment: Students will complete the Mathematical Principles Challenge. Linkages Cams Turnbuckles Pulleys Gears Key Fasteners V-Belt Drives Chain Drives Visual Spatial Musical Rhythmic Bodily Kinesthetic Intrapersonal Interpersonal Naturalist Existentialist Application Guided Practice (LSI Quadrant III): Teacher will observe student teams as they work on the Mechanical Advantage Team Project. Independent Practice (LSI Quadrant III): Have student teams evaluate everyone’s Mechanical Advantage Team Project presentations and explain what they would change on their own for next time. Summary Review (LSI Quadrants I and IV): Question: What type of mechanical system do you use often? Answer: Answers will vary. One possible answer: Question: What is the mechanical advantage of a mechanical system? Answer: Again, answers will vary. Question: What is the Newton Spring Scale? Answer: Again, answers will vary. Question: What were the mechanical advantage units of measurement for simple machines? Answer: Again, answers will vary. Question: What is the mechanical advantage of the gear drives? Answer: Again, answers will vary. Evaluation Informal Assessment (LSI Quadrant III): The teacher will observe the students as they complete the mechanical advantage team project. Look for teamwork and professionalism. Copyright © Texas Education Agency, 2012. All rights reserved. 8 Formal Assessment (LSI Quadrant III, IV): 1. Establish Project Team Protocol, establishing roles and tasks. 2. Complete tasks listed on team contract and the Mechanical Advantage Team Project. 3. Presentation of teams Mechanical Advantage Team Project. Extension Extension/Enrichment (LSI Quadrant IV): For more enrichment, students should produce a formal write-up, including reflection questions asking them to apply what they’ve learned about the Mechanical Advantage Team Project. Copyright © Texas Education Agency, 2012. All rights reserved. 9 Mechanical Systems Vocabulary Mechanical Systems: machines that use energy to perform some activity Mathematical Principles: principles taught and learned in an equitable manner in a setting that ensures that problem solving, reasoning, connections, communication, and conceptual understanding are all developed simultaneously along with procedural fluency Simple Machines: mechanical systems that change the direction or magnitude of a force; the term refers to the six classical simple machines, which were defined by Renaissance scientists Lever: a simple machine consisting of a rigid bar that rests on a fulcrum, or pivot Wheel and Axle: a simple machine consisting of a wheel connected to an axle so that turning the wheel also turns the axle Pulley: a simple machine consisting of a grooved wheel that is turned by a rope or chain Inclined Plane: a simple machine consisting of a uniform sloped surface Wedge: a simple machine consisting of an angled object used to separate two objects, lift an object, or hold an object in place Screw: a simple machine consisting of an inclined plane wrapped around an axis Linkages: include garage door mechanisms, car wiper mechanisms, gear shift mechanisms Cams: rotating or sliding pieces in a mechanical linkage used especially in transforming rotary motion into linear motion or vice-versa Turnbuckles: devices for adjusting the tension or length of ropes, cables, tie rods, and other tensioning systems Gears: rotating machine parts having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque; two or more gears working in tandem are called a gear train or a gear drive Key Fasteners: any of various devices, as a snap or hook and eye, for holding together two objects or parts sometimes required to be separate, as two edges or flaps of a piece of clothing Copyright © Texas Education Agency, 2012. All rights reserved. 10 V-belt Drives: belts with a flat bottom and tapered sides, used to transmit motion between two pulleys Chain Drives: two or more gears connected with a chain that provide a way of transmitting mechanical power from one place to another Fulcrum: the center or axis of rotation of the system Moment Arm: the distance from any force or weight that produces torque to the fulcrum Force Arm: the distance from an applied force to the fulcrum (the moment arm of the force) Resistance Arm: the distance from the resistance to the fulcrum (the moment arm of the resistance) Copyright © Texas Education Agency, 2012. All rights reserved. 11 Team Contract Spreadsheet Name: Date Assigned Name: Date Assigned Name: Date Assigned Name: Date Assigned Date Due Assignment Date Complete Late? Date Due Assignment Date Complete Late? Date Due Assignment Date Complete Late? Date Due Assignment Date Complete Late? Team Signatures: _________________________ _________________________ _____________________________ _________________________ Copyright © Texas Education Agency, 2012. All rights reserved. 12 Misc. sketches and/or ideas: Team Member #1: Date: Team Member #2: Class: Team Member #3: Grade: _________/100 points Simple Machines Challenge Criteria Categories Criteria (Content/Skills To Be Addressed) Novice 0-16 pts Developing 17-19 pts Accomplished 20-22 pts Exemplary 23-25 pts Team contract was never completed. Team members did not work together. Team contract was incomplete. Each member was not clear on their role. The team members did not work together. Team contract was completed and roles assigned. Each member was not clear on their role. Team members did not work together all the time. Team contract was completed and roles assigned. Each member is clear on their role. Team members worked welltogether. There was no simple machine constructed or the team used none of the design principles in their simple machine design. The simple machine was poorly designed and lacked documentation. The team considered only a few of the design principles in their simple machine design. The simple machine was not welldesigned and documentation was lacking. The team considered most design principles in the simple machine design. Construction was adequate, but the team lacked documentation. The team considered the appropriate design principles in the simple machine design. Construction was welldocumented and could be easily replicated. The team did not examine another team’s simple machine. Thus, they made no effort to compare and contrast their machines. The team examined another team’s simple machine, but made no effort to compare and contrast their machines. The team examined another team’s simple machine. Most of the similarities and differences were documented. The team examined another team’s simple machine and documented similarities and differences. The team did not complete the calculations of the mechanical advantages of each team’s simple machines. The team calculated the mechanical advantage of each team’s simple machine. However, some calculations were incorrect. The team calculated the mechanical advantage of each team’s simple machine. They documented most of their calculations. The team calculated the mechanical advantage of each team’s simple machine. Documentation of all calculations was evident. Total: Team Contract Design and Construction Comparison Between Simple Machines Mathematical Calculations Teacher Notes: Points Earned Copyright © Texas Education Agency, 2012. All rights reserved. 13 Misc. sketches and/or ideas: Team Member #1: Team Member #2: Date: Class: Team Member #3: Grade: _________/100 points Lever and Pulley Challenge Rubric Criteria Categories Criteria (Content/Skills To Be Addressed) Research and Plan Technical Drawing of Design Novice 0-16 pts Developing 17-19 pts Accomplished 20-22 pts Exemplary 23-25 pts Research was not relevant to the problem. The research did not include the proper information. The plan had hardly any details and/or is not easy to follow. Research selected was sometimes relevant, but not always accurate and complete. The team did not explore any facets of lever and pulley design. The plan had limited details. Research selected was relevant and was mostly accurate and complete. The team explored some facets of the lever and pulley design. The plan included how they addressed design principles and was easyto-follow. Research selected was highly relevant to the problem. The team examined different facets of lever and pulley design. The plan included how they addressed design principles. The plan was detailed and easy-to-follow. No design drawing or reading and understanding drawing was difficult. Minimal idea development was evident. The plan had no key details or dimensions, or contained unrelated details. Drawing needed improvement. There was poor idea development and sequencing between sketch and drawing. There are unelaborated and/or repetitious details. Most key details and dimensions were missing. Drawing communicated design. Some idea development was supported by relevant details. Drawing details made major points easy to follow. Drawing contains most key details and dimensions. Drawing communicated design clearly. There is evidence of analysis, reflection and insight. Drawing contains all key details and dimensions. Points Earned Copyright © Texas Education Agency, 2012. All rights reserved. 14 Design and Construction Presentation There was no lever or pulley system constructed or the team used none of the design principles in their lever or pulley design. The lever or pulley was poorly designed and lacked documentation. The team considered only a few of the design principles in their lever or pulley design. The lever or pulley was not well-designed and documentation is lacking. The team considered most design principles in the lever or pulley design. The pulley or lever was welldesigned and the team lacked documentation. The team considered the appropriate design principles in the lever or pulley design. Design was welldocumented and could be easily replicated. Material was not related to the research and plan. Points are vague and the team could not explain why they chose a particular type or class of pulley or lever. Information is not presented in a logical sequence and makes it hard to follow. Poor visuals (if any) are not included and/or there are numerous misspellings or grammar errors. Material was not always related to the research. Few points supported why the team chose a particular type or class of lever or pulley. Information was not well presented. There are several misspellings and/or grammar errors. Material was clearly related to the research and plan. Most points supported why the team chose a particular type or class of lever or pulley. Information was supported in a logical manner, which the audience can follow. Good visuals were included, but the presentation had some misspellings and/or grammatical errors. An abundance of material was clearly related to the research was presented. Points are clearly made to describe why the team chose a particular type or class of lever or pulley system. Information was presented in a logical and interesting sequence, which the audience can follow. Good visuals were included. The presentation had no misspellings or grammatical errors. Teacher Notes: Total: Copyright © Texas Education Agency, 2012. All rights reserved. 15 Misc. sketches and/or ideas: Team Member #1: Team Member #2: Date: Class: Team Member #3: Grade: _________/100 points Mathematical Principles Challenge Rubric Criteria Categories Criteria (Content/Skills To Be Addressed) Mechanical Advantage Calculations Documentation Paper Spelling; Grammar; Conciseness Presentation Teacher Notes: Novice 0-16 pts Developing 17-19 pts Accomplished 20-22 pts Exemplary 23-25 pts Team members did not use a clear procedure to derive the mechanical advantage. Many calculations were incorrect and/or there was no documentation of how the calculations were derived. Team members utilized procedural fluency to perform the mechanical advantage calculations. Several calculations were incorrect or the team did not document how they were derived. Paper is not well-organized. The logic is sometimes not easy to follow. Team members utilized procedural fluency to perform the mechanical advantage calculations. Most calculations were correct and welldocumented on how they were derived. Team members utilized procedural fluency to perform the mechanical advantage calculations. All calculations were correct and welldocumented on how they were derived. Paper is coherently organized, but sometimes the logic is not easy to follow. The paper has 1-2 spelling or grammatical errors. Writing is clear and concise. Technical terms are not clearly defined. Paper is coherently organized and the logic is easy to follow. Presentation clearly demonstrates how the mechanical advantages are calculated. Documentation supports most of the conclusions. The presentation is between 7-8 minutes in length. Presentation clearly demonstrates how the mechanical advantages are calculated. Documentation supports all conclusions. The presentation is between 9-10 minutes in length. Total: There was no paper written and/or the paper is poorly organized and difficult to read. There was no paper written and/or it had numerous spelling or grammatical errors. Writing was not clear and concise. Technical terms are not clearly defined. There was no presentation or the presentation did not demonstrate how the mechanical advantages are calculated. Documentation of conclusions is lacking. The presentation was under 5 minutes. The paper has more than 2 spelling or grammatical errors. Writing is not always concise. Technical terms are not clearly defined. Presentation did not always demonstrate how the mechanical advantages are calculated. Documentation of conclusions is weak. The presentation is between 5-6 minutes in length. Points Earned The paper has no spelling or grammatical errors. Technical terms are clearly defined. Writing is clear and concise. Copyright © Texas Education Agency, 2012. All rights reserved. 16