Lecture No. 1

Introduction

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Course Offering

ME 553 - Kinematics and Dynamics of MachineryFall, 2008

Call Number:14915 Instructor: G.L. KinzelE-Mail: kinzel.1@osu.edu Office: E345 Scott LaboratoryPhone: 292-6884 (O), 459-5125 (H) Office Hours: Monday 1:30-2:30

TR 10:00-11:00

Class times: Tue and Thurs 12:00 - 1:48 Location: E001 Scott LabPrerequisites: ME 430, 250, 561 & Eng Major or Permission of InstructorWeb Page: www.carmen.osu.edu

Required Text: Kinematics, Dynamics, and Design of Machinery, 2ed. by K Waldron and G. Kinzel, John Wiley and Sons, Inc., 2004.

Required Equipment: drafting triangles, compass, protractor, scale

Prerequisite for: ME 563 Design of Selected Machine Elements IIME 751 Application of Computer Graphics to Kinematic

h i d l i ( ff d i )

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Synthesis and Analysis (offered Winter Quarter)

Mechanism Overview

OVERVIEW ME 553 d l ithOVERVIEW: ME 553 deals with:a) The kinematics and rigid-body dynamics of machine

components. pb) The motion and force analysis in mechanisms (Cams

and linkages) c) Design of planar linkages and simple cam systemsc) Design of planar linkages and simple cam systems

BACKGROUND: ) St ti d d i (410 & 430) l i ita) Statics and dynamics (410 & 430) are real prerequisites

b) Need to know solid modeling from somewhere (ME 561)c) Review topics if not comfortable with them.

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Important Dates

Tuesday January 5 First Class MeetingFriday January 22 Last Day to Drop Without a “W” or Add

Without PetitioningThursday February 11 Midterm ExamTh d F b 18 Will t t h idt d dThursday February 18 Will try to have midterms gradedFriday February 19 Last Day to Drop Without Petitioning (contact

me first though)Thursday March 11 Project Presentations 5:30 – 9:00 p mThursday March 11 Project Presentations, 5:30 – 9:00 p.m.Tuesday March 16 Final Exam, 1:30-3:18 p.m.

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Grading

GRADING: The course grade will be based on the following:Midterm 30% 94-100 A 73-75.9 CFi l 25% 90 93 9 A 70 72 9 CFinal 25% 90-93.9 A- 70-72.9 C-Homework 15% 86-89.9 B+ 65-69.9 D+Attendance 10% 83-85.9 B 60-64.9 DProject 20% 80 82 9 B 0 59 9 EProject 20% 80-82.9 B- 0-59.9 E

100% 76-79.9 C+

In addition, I reserve the right to add up to 5 points to a student’s finalaverage if I do not believe that the average reflects accurately the student’soverall performance in the class. However, I will never add points if thest dent’s pe fo mance on the home o k and/o p oject is poo o if thestudent’s performance on the homework and/or project is poor or if thestudent’s attendance record is poor. Also, I will not add points to the finalaverage if it raises the final score above the homework average.

5The class average is typically around 2.8.

Exams

EXAMS: If you do not appear for a scheduled exam, you will bei d f th t F b t b dgiven a zero grade for that exam. For an absence to be excused, you

will need a written explanation signed by a physician specifying that youwere medically unable to attend. Standardized forms (such as issued by thehealth center) will not be accepted All exams will be closed bookhealth center) will not be accepted. All exams will be closed book.However, an 8.5 x 11 inch sheet of equations (no worked problems) may bebrought to each exam. These equation sheets will be handed in with theexams The midterm will be given on Thursday, February 22 fromexams. The midterm will be given on Thursday, February 22 from2:30 to 4:18, and the final exam will be given on Tuesday March 16from 1:30 - 3:18 pm.

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Attendance

Attendance will be taken at random times during the quarter. I have found that on average, students who attend class perform significantly better on the exams than those who do not. In general, I will present the theory in g p ythe class using slides and work examples on the chalkboard. It will benefit all of the students to see the examples. I expect to take attendance approximately 10 times during the quarter so each class missed will mean a d d f f f l f h ldeduction of one point from your final average for the class.

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Homework

a) Homework problems will be assigned during almost every class meeting.

b) U l th i t t d h k i d i l k f thb) Unless otherwise stated, homework is due in class one week from the day it was assigned.

c) All assigned homework problems will be collected, but only one problem in each set will be graded by my graderin each set will be graded by my grader.

d) An effort will be made to post solutions to the problems that are not graded.

e) Late homework will not be accepted.e) Late homework will not be accepted. f) Students are encouraged to work together on the homework

assignments; however, every student must individually submit a homework assignment that consists of his/her own work. g /

g) Submitting homework that is copied in any portion from another source, including another student’s work, constitutes academic misconduct and will be reported as such.

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h) The homework must be written according to the homework format. One point will be subtracted for each major step omitted. You can receive a zero even though your method and answer are nominally correct.

Extra Accommodations

Any student who feels that he/she may need and ti b d th i t f di bilit h ldaccommodation based on the impact of a disability should

contact the instructor privately to discuss his/her specificneeds. The instructor will work with the student and theOffice of Disability Services at (614) 292-3307 in 150Pomerene Hall to coordinate reasonable accommodations forstudents with documented disabilitiesstudents with documented disabilities.

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Course Objectives

Each student will learn to:1. To model real mechanisms for mobility, position, velocity, and

acceleration.2. To design linkages for rigid-body guidance, rocker amplitude,2. To design linkages for rigid body guidance, rocker amplitude,

path generation, and function generation.3. To analyze and design cam/follower mechanisms.4 To use both graphical and analytical approaches to mechanism4. To use both graphical and analytical approaches to mechanism

analysis.5. To perform force analysis of mechanisms using energy-based

methods.6. To work as a team employing computer-based productivity

tools in a project setting.

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tools in a project setting.

Tentative Schedule

DATE TOPIC TEXT

Tuesday, January 5 Introduction, joints, planar linkages 1.1 – 1.6

Thursday, January 7 Mobility, idle degrees-of-freedom 1.7 – 1.9

Tuesday January 12 I i G h f i i i li i i f 1 10 1 19Tuesday, January 12 Inversion, Grashof criterion, motion limits, interference 1.10 – 1.19

Thursday, January 14 Design for motion generation 6.1 - 6.3

Tuesday, January 19 Design for motion generation, continued 6.3

Tuesday, October 21 Design for function generation 6.4

Tuesday, January 26 Design for rocker amplitude, cognate linkages 6.5 – 6.6

Thursday, January 28 Cam design, motion programs 8.1 – 8.9

Tuesday, February 2 Graphical and analytical methods in cam profile layout 8.10

Thursday February 4

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Thursday, February 4 Analytical four-bar analysis 5.1 – 5.4

Tuesday, February 9 Analytical slider-crank analysis 5.5 – 5.6

Tentative Schedule (Cont’d)

Thursday, February 11Midterm Examination

Tuesday February 16 Vector loop method of analysis 5.7 – 5.13Tuesday, February 16 p y

Thursday, February 18 Velocity & acceleration polygons 2.1 – 2.4

Tuesday, February 23 Polygon examples, image theorems, inversion 2.5 – 2.9

Thursday, February 25 General velocity/acceleration equations 3.1 – 3.4

Tuesday, March 2Special applications of velocity and acceleration equations 3.5 – 3.8

Thursday, March 4 Instant centers 4.1 – 4.14

Tuesday, March 9 Instant centers, energy methods in force analysis 13.9 – 13.10

Thursday, March 11Static force analysis of mechanismsProject Presentations 5:30 – 9:00 p.m.

13.1 – 13.8

Tuesday, March 16 Final Examination, 11:30 a.m.

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Homework Format

GENERAL1. All homework must be written neatly on straight lines. If necessary, use lined y g y,

paper. 2. Use only one side of the paper.3. The first page should be left blank except for the following information: student's

name class section date due and the homework numbername, class section, date due, and the homework number.4. Start each long problem on a new page (it is not necessary to do this for each

part of a question, however) unless the problem is very brief. If more than one problem is included on a given page, separate the problems with a horizontal dividing line.

5. Number the pages consecutively6. Staple all pages together in the proper order.7 Ample margins (about 1 inch) should be provided at all four edges of the sheets7. Ample margins (about 1 inch) should be provided at all four edges of the sheets.

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Homework Format (Cont’d)

NUMERICAL PROBLEMS1. Write down the problem statement complete with sketches.2 E l i l ti i d2. Explain your solution sequence in words 3. Show details of your calculations and identify the answer(s) with a

surrounding box.4 Never show a calculation without the algebraic form of the equation4. Never show a calculation without the algebraic form of the equation

given first.5. Actual calculated results should be shown to only sufficient decimals to

indicate the expected accuracy of the computationsindicate the expected accuracy of the computations.

DRAWINGS1. Use a sharpened pencil and make accurate sketches/drawings.p p / g2. Use a ruler or straight edge to draw straight lines and a compass or

template for circles.*************************************************************

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Note: 10% will be deducted for each applicable step which is neglected

MATLAB Programs Available (1st Edition)

Location DescriptionFootpump Analysis Files for analyzing a footpump mechanismFour Bar Analysis Four bar linkage analysis routinesFour Bar Analysis Four-bar linkage analysis routines Rigid Body Analysis Analysis of rigid body is two points are knownSlider Crank Analysis Slider-crank linkage analysis Six Bar Mechanism MATLAB program for analyzing a six bar linkageInverted Slider Crank Inverted slider crank analysisInverted Slider Crank Inverted slider-crank analysis RPRP Analysis RPRP mechanism analysis with either slider or crank as driverRRPP Analysis RRPP mechanism analysis with either slider or crank as driverElliptic Trammel Elliptic trammel mechanism analysis Oldham Analysis Oldham mechanism analysis with either slider or crank as driverOldham Analysis Oldham mechanism analysis with either slider or crank as driverRectangle & Frameline Programs for coordinates of rectangle and framelineRigid Body Guidance Program for design of linkage for 3 positions for rigid body guidanceFunction Generation MATLAB program for function generationCrank Rocker Design MATLAB program for crank rocker designCrank Rocker Design MATLAB program for crank rocker designCam Design MATLAB program for cam designInflection Circle Prog. MATLAB program computing the inflection circle for four bar linkageCentrode Plot MATLAB program computing centrode for four-bar linkage programSC Shaking Force Program for computing the shaking force for slider crank mechani

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SC Shaking Force Program for computing the shaking force for slider crank mechaniCoupler Curve Gen. Coupler curves for a four-bar linkage and slider crank programCognate Drawing Computes the cognates linkages for a four-bar linkage

MATLAB Programs Available (2nd Edition)

-See web on how to run programs-

Programs Under LinkageDesign1) Crank Rocker Design (CRDesign)1) Crank Rocker Design (CRDesign)2) Cognate determinations of a four bar linkage (CognateAnalysis)3) Design of double rocker linkage (DoubleRockerDesign)4) Simple four bar linkage analysis (FourbarAnalysis)5) Simple slider crank linkage analysis (SliderCrankAnalysis)6) Six bar analysis program (SixbarAnalysis)7) Simulation of Hrones & Nelson coupler curve atlas for four-bar linkages (HR CrankRockerAnalysis)8) Simulation of Hrones & Nelson coupler curve atlas for slider-crank linkages (HRSliderCrankAnalysis)9) Display of four-bar linkage centrode curves (CentrodeDesign)10) Display of four-bar linkage inflection circle and calculation of center of curvature (Inflection4barAnalysis)11) Analysis of shaking forces in slider-crank mechanism (ShakeAnalysis).

Programs Under Cam Design1) One program, Cam2.

Programs Under Rigid Body Guidance Design1) Rigid-body guidance or motion generation using a four-bar linkage (RBG4barDesign)1) Rigid body guidance or motion generation using a four bar linkage (RBG4barDesign)2) Rigid-body guidance or motion generation using a crank-slider mechanism (RBGCrankSliderDesign)3) Rigid-body guidance or motion generation using a slider-crank mechanism (RBGSliderCrankDesign)4) Rigid-body guidance or motion generation using a double slider or elliptic trammel mechanism (RBGElTrammelDesign)

Programs Under Gear Design

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1) Arb2ThDesign) will compute and draw the tooth profile conjugate to an arbitrarily specified tooth form2) GeardrDesign) will draw an involute profile given the parameters of the hob used to generate the gear form

Student Grievances

Process:1) The student should first talk to faculty member or instructor involved2) If the difficulty is not resolved, the student may make an appointment with the department’s

Coordinator of Undergraduate Academic Advising. g g3) If satisfactory resolution does not occur, the student may take the grievance to the department’s

Associate Chair.

4) If satisfactory resolution does not occur, the student should notify the department’s Chair.

Information can be obtained from the Office of Undergraduate Academic Advising (Faculty Rule 3335-7-23).

Grievances concerning graduate teaching and research associates should be submitted first to the supervising instructor, then to the Coordinator of Undergraduate Academic Advising, and if necessary, to the department’s Associate ChairAssociate Chair.

Coordinator of Undergraduate Academic Advising: Rosie Quinzone-Bonello (N250D Scott Laboratory)Quinzon-bonello.1@osu.edu614-292-0515

Associate Chair Gary Kinzel (E345 Scott Laboratory)Associate Chair Gary Kinzel (E345 Scott Laboratory)kinzel.1@osu.edu614-292-6884

Chair Krishnaswamy Srinivasan (N350C Scott Laboratory)srinivasan.3@osu.edu

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614-292-0503

This information is given on the web site: http://www.mecheng.ohiostate.edu/docs/undrgrad/Procedure_ Grievance%20and%20Solving%20Problems.pdf

Academic Misconduct

1) The use of University Computing Resources for expressly committing or facilitating the commission of Academic Misconduct is prohibited by the Policy of the Office of Information Technology: http://cio.ohio-state.edu/policies/use_policy.html

2) Academic Misconduct is described as "any activity that tends to compromise the academic integrity 2) Academic Misconduct is described as any activity that tends to compromise the academic integrity of the university, or subvert the educational process." Pertinent examples include, but are not limited to:

• Knowingly providing or using assistance in the laboratory, on field work, or on a course assignment unless such assistance has specifically been authorized;such assistance has specifically been authorized;

• Submitting plagiarized work for an academic requirement. Plagiarism is the representation of another's work or ideas as one's own; it includes the unacknowledged word-for-word use and/or paraphrasing of another person's work, and/or the inappropriate unacknowledged use of another person's ideas;

• Submitting substantially the same work to satisfy requirements for one course that has been submitted in satisfaction of requirements for another course, without permission of the instructor of the course for which the work is being submitted;

• Engaging in activities that unfairly place other students at a disadvantage, such as taking, hiding or altering resource material, or manipulating a grading system.

In particular, website posting, using University Computing Resources, solution manuals, worked problems (whatever the source), laboratory reports, or any material which may be turned in as an assignment for an offered course is expressly prohibited.

Any violations of the above policy will be reported to the University Committee on Academic

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Any violations of the above policy will be reported to the University Committee on Academic Misconduct. Students who violate the policy may also be denied access to University Computing Resources.

This information is given on the web site: http://www.mecheng.ohio-state.edu/students/comppolicy.html

Project Description

Project DescriptionThe project will be completed by a team of 4-6 students. The objective is to design p j p y j gand build a linkage that will solve one of the problems detailed below. The linkage must be a one-degree-of-freedom device and consist of all rigid members (unless explicitly stated otherwise). Also, the linkage must incorporate at least one 4-bar linkage slider crank or slider crank inversion You must build a physical model of thelinkage, slider-crank, or slider-crank inversion. You must build a physical model of the linkage that can fit on a 2-ft x 2-ft board.

Deliverables:1) A functioning prototype2) A written report describing the design and fabrication of the linkage3) A Powerpoint presentation giving an overview of the design4) An animation of the linkage using a solid modeling program4) An animation of the linkage using a solid modeling program5) A CD with all written material and supporting documentation

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Project Dates

Proposal Date:On February 16, submit a 3-page proposal identifying the problem on which your team will be working. In the proposal, give dimensions for the frame mounted joints and any other parameters that are relevant to the problem. The first page of the proposal must be blank except for the project name, date, and the names and pictures of the team members. On the second and third pages, describe at least one design concept and give details about the design constraints and how you plan to solve the problem.

Completion Date:You will demonstrate your design on Thursday, March 11, between 5:30 and 9 p.m. in E100. If you have a conflict during part or all of this time, include an explanation of the conflict as an extra page in your proposalas an extra page in your proposal.

Task Details:On March 11, you will have 10 minutes to explain your design and to demonstrate that it solves the problem identified At the beginning of your team's demonstration one person from thethe problem identified. At the beginning of your team s demonstration, one person from the group will give a brief presentation using PowerPoint on the design while the rest of the team sets up the mechanism. I will select the person who will give the presentation immediately before it is your team's turn. Therefore, each person in the team must be prepared to give the presentation.

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Report, Animation, and CD

Written ReportThe final report for the project must be in both hard copy and electronic form (.doc or .pdf format), and all text and equations must be typed. All drawings, photographs, and textformat), and all text and equations must be typed. All drawings, photographs, and text must be contained in the report. Do the solid models and animation with SolidEdge. For the animation, show the motion of the linkage in general. Draw additional figures using a program like AutoCAD or the draft feature in SolidEdge.

AnimationFor the animation, show the motion of the linkage in general using a solid modeling program. Change the color of the individual links so that they stand out. Use the motion feature under the environment tab and create an AVI movie of the animation If you do not know how to do thisenvironment tab and create an AVI movie of the animation. If you do not know how to do this, see the tutorials provided with the solid modeling programs. The procedure is simple, and the tutorials are informative.

CD C t tCD Contents1) Report in MS Word or pdf format. .2) Solid-modeling files for, parts, drafts, assembly, and movie. Provide an IGES file for the assembly.3) “R d " fil l i i h t bl th h i i th lid d li d

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3) “Readme" file explaining how to assemble the mechanism in the solid modeling program and how to conduct the animation.

Design Procedure and Extra Credit

Design ProcedureYou are expected to use one of the formal design procedures covered in class. Significantly reduced credit will be given for designs based on trial and error.

Bonus PointsBonus Points5 bonus points will be awarded for the best linkage as determined by a majority of the class.

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Project Options

1) Walking machine: Design a mechanism to serve as the leg of a walking machine such that it drives the foot through a typical walking stride. See www.strandbeest.com for inspiration.

2) Vehicle roof rack assist: Design a mechanism to assist an individual in loading objects such as luggage, canoes, skis, etc., onto the roof of a vehicle.

3) Design of Trenching Attachment for a Farm Tractor: Design a trenching device that will attach to the three-point hitch on a tractor and can be powered using the power takeoffwill attach to the three point hitch on a tractor and can be powered using the power takeoff.

4) Rocking-Chair Simulator: Design a rocking chair simulator that takes up the same floor space as a normal Boston Rocker and moves with the same motion.

5) Efficient Windshield Wiper: Design a new wiper system that can be retrofit on existing d ill l l 95 f h i d hi ldcars and will clean at least 95 percent of the windshield.

6) Shoe Tester: Design a machine that will wear test shoe soles for a typical walking cycle. 7) Spring-Linkage Counterbalance: Design a mechanism to counterbalance a tool that

weights 50 pounds over a length of 2 feet in the vertical direction so that an assembly line g p g yworker does not have to strain him/herself to use the tool.

8) Solar Panel Tracking Mechanism: Design a linkage with a constant velocity input that will track the north-south movement of the sun at noon from winter to summer.

9) Team Defined Mechanism: Your team may also come up with a project of your own

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9) Team Defined Mechanism: Your team may also come up with a project of your own choosing as long as it is at least as involved as the ones above, and it requires one of the design procedures covered in class

Project Final Report

1) The final report will be approximately 15 pages long. The reports should contain the following:2) The front page of the report should contain the project title, date, picture of device, and pictures and names

of the team members.3) The main report follows the title page. The report must contain the following sections that will be separated) p p g p g p

by headings.a) Introduction - This should explain the purpose of the device and should detail the constraints. Note that

these constraints will include the ones given on the problem sheet along with others that the team identifies. Include a problem statement with a good photograph of the linkage environment, a scale drawing or photograph of your linkage model and a description of the linkagedrawing or photograph of your linkage model, and a description of the linkage.

b) Description of design process and design. Tell how you arrived at the design and describe in detail your design. Identify the subsystems in the device and explain what each subsystem does. Note that you are expected to use one of the formal design procedures covered in class. Reduced credit will be given for trial and error designs.

c) Show the design process using either graphical or analytical procedures. Show design details on howyou determined the link lengths and pivot locations. Be specific and not descriptive.

d) Write a conclusions section telling the good and bad aspects of the design.4) When writing the report, include a figure caption below each figure. Also, refer to every figure in the text

In general use figures when describing physical aspects of the designIn general, use figures when describing physical aspects of the design.5) Include a caption above any tables. Refer to the tables in the text.6 )The report must be produced using MS Word (or .pdf format) and delivered in both written and electronic

form.7 )Type any equations used in the report, and assign equation numbers to any equations that you refer to in

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the text.8) On the final page of the report, indicate the contributions of each team member to the project. Write 2-3

lines for each team member.9) Be sure to use page numbers.

Project Grading

Grading:Design proposal: 5%R 20%Report 20%Design quality 35%Presentation 15%Animation 5%Animation 5%Peer review 20% (You will provide this information

on the final exam)

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Project Web Page

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Project Web Page (cont’d)

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