6. EGR 352: Kinematics and Dynamics

6.1 Philosophy

• The best way to learn kinematics and dynamics analysis is by solving problems.

• A project will be used to enforce the design aspects of the course.

6.2 Resources

6.2.1 The Web

The Web site ‘http://claymore.engineer.gvsu.edu’ should be used as an active reference for all students. Up to date information will be stored here, and can be printed. At the beginning of the term each student will be given an account on this machine, and will have a basic web page set up. During the term all work that is done will be added to these web pages. You are welcome to add additional information in this form. Note: assignments will be submitted by adding them to the web pages.

6.2.2 Software

Working Model: A very powerful software package for modeling the dynamics of mechanical systems. This will allow simulation of mechanical systems quickly and easily. It can import dxf files from autocad for geometry, and export numbers to other packages, such as excel. A tutorial guide will be provided, and students are welcome to purchase a student edition. There is also a free (but limited) demo version available that will basically allow practice and viewing of other working model files.

MathCAD: This package will do symbolic and numerical analysis of mathematics. This package will also produce graphs. Each student is expected to be familiar with all aspects of this package. Manuals are available.

AutoCAD: A primary tool for generation of drawings and geometry. This will be used to produce drawings (note: use dxf formats working model applications and gif for web applications).

Netscape Communicator: this package will allow web browsing, and it also has a built in editor so that you may update files for home pages. This can be obtained on-line at no cost.

Excel: This or another spreadsheet may be used to produce better plots than what has been obtained in working model. It is also possible to do some calculations with it.

FTP/Telnet: FTP will allow you to download and upload files to the web server. When updating web pages you must download the ‘html’ file, edit it locally, then upload it to the remote machine. This utility should be available on all networked PCs.

6.2.3 References/Bibliography

6.12 Chironis, N.P., Sclater, N., Mechanisms and Mechanical Devices Sourcebook, 2nd Edition, McGraw-Hill, 1996

6.13 Erdman, A.G. and Sandor, G.N., Mechanism Design Analysis and Synthesis, Vol. 1, 3rd Edition, Prentice Hall, 1997.

6.14 Jones, F.D., Ingenious Mechanisms for designers and inventors, Industrial Press Inc., Volumes 1-4, 1930.

6.15 Shigley, J.E., Uicker, J.J., Theory of Machines and Mechanisms, 2nd Edition, McGraw-Hill, 1995.

6.3 Assignments

• The assignments are to be done individually from beginning to end. My experience shows that study groups are of great help, and will help a student get by many small problems quickly. But students who never do any problems individually (i.e., assignments) always do poorly when they must solve problems themselves on exams.

• Stassen’s Ten Commandments for Assigned Calculations

The following format requirements must be met before an assignment will be accepted or given credit.

1. The problem must be clearly identified at the top left of the page. The name of the author must be placed at the upper right-hand corner of the front page.

2. All calculations must be shown and a clear “heading” must be given with each step of the calculations.

3. All units must be attended to properly in balanced equations. Answers without units are not valid, except 0, variables, or unitless values such as ratios.

4. Where applicable, references must be given for all uncommon relationships or empirical values obtained from textbooks.

5. Clear diagrams must be provided where necessary.

6. Do not use unnecessary terms like “I” or verbose terms such as “to find”, etc. It is expected that proper and concise statements are made where needed.

7. At the conclusion of each problem the final result must be clearly summarized and indicated.

8. Where necessary a conclusion should be drawn or a final comment made. Sometimes a recommendation is necessary and should be included in the report.

9. Reports must be written on one side of letter size paper. Only in the case of graphic solutions can “odd” paper sizes be used, but these must be folded to size. Computer based work should print nicely on letter size paper.

10. Calculations should progress in a logical and sequential manner to the final result.

6.4 Project

• The project will be discussed in class, but basically a complex mechanism of some sort will be designed and constructed on a competitive basis. Students are encouraged to present the results of their work at the student research day in April. Potential topics include,

a large catapult, or equivalent device, that is capable of projecting a payload of at lead 10 pounds a distance greater than 100 feet. This device should be easy to move, and can be recharged without special power sources. This is a team project.

write programs in Java to do various elements of kinematic design. This would be an individual project(s).

an autoloader for a keytag rounder

other project ideas will be entertained

6.4.1 Previous Project Topics

Disc Brake Redesign: Beard, J.: A novel disc brake will be designed using a linkage to actuate the callipers. The design will be simulated, and a model will be built to test the concept.

Catapult: Cummings, J., Freeman, T. and Ramsdell, S.: A catapult or equivalent mechanism will be designed for general use in the department. The design will be portable and capable of launching a 10 pound projectile up to 100 feet. A design will be selected, simulated, built and tested.

Java Applets: Jamison, D.: Applets will be written in Java to help some aspect of kinematics. This will include learning Java, selecting a program objective, writing code, and debugging.

Light Vehicle Loader: Jezewski, C.: To load a snow mobile or waterski onto a pickup truck a mechanism will be designed that can be operated by hand. This mechanism should be lightweight, but allow easy operation. The definition of requirements, design. simulation, construction and testing will be done.

Auto Pitcher: Maxim, J.: The machine will lob balls straight up from a base so that a child may practice batting skills. The balls will be thrown to variable heights to accommodate different batter sizes. The machine will be designed, analyzed, simulated, built and tested.

Stamped Parts Sorting: Mead, M.: To sort good and bad parts that have just been stamped, a mechanism will be designed for ejecting bad parts.

Java Applets: Stehouwer, C.: Applets will be written in Java to help some aspect of kinematics. This will include learning Java, selecting a program objective, writing code, and debugging.

Prosthetic Knee: Wiersma, J.: The motion of a knee is complex, but can be approximately modeled with a mechanism. A mechanism will be designed, simulated, constructed and tested. Final data values will be compared to physiological data.

6.5 Problems and Reading

6.5.1 Erdman and Sandor

• The following section, and problems are suggested in the text,

Chapter 1: Introduction to Kinematics and Mechanisms

Read Sections: 1-9
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 2, 4, 11, 19, 25, 36, 52
Required Problems: 16(MC), 27(MC), 61(MC), 16(WM)

Chapter 2: Design and Computer Aids

Read Sections: 1-6
CDRom: N/A
Suggested Problems: N/A
Required Problems: N/A

Chapter 3: Displacement and Velocity

Read Sections: 1-11 (only skim 2), appendix
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 1, 3, 6, 9(use complex method), 12, 23c), 36b), 63b), 71(wm)
Required Problems: 8(MC), 24c)(MC), 24c)(WM), 52c)(MC)

Chapter 8: Mechanisms Synthesis

Read Sections: 1-3, 13-15
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 10, 17, 20b)
Required Problems: 21 b)(MC), 21(WM)

Chapter 4: Acceleration

Read Sections: 1-5
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 5, 9, 37, 58
Required Problems: 13(MC), 13(WM), 42(MC)

Chapter 5: Mechanism Dynamics

Read Sections: 1-7 (only skim sections 2-5)
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 1, 19, 23
Required Problems: 8 e)f)(MC), 8 e)f)(WM)
Chapter 6: Cams

Read Sections: 1-6, 8-10

CDRom: Look at the sample problems for the chapter.
Suggested Problems: 1, 7, 37
Required Problems: 35 (Develop the geometry for the cam in Mathcad. Export the geometry to Autocad via a text file. Export the geometry in DXF format to Working Model and simulate the motion.)

Chapter 7: Gears

Read Sections: 1-9
CDRom: Look at the sample problems for the chapter.
Suggested Problems: 1, 2, 3, 16
Required Problems: 6 (Design matching gears. Create the geometry in Autocad. Export this geometry to Working Model and simulate their operation.)
6.6 Professional Presentations

• Presentations will be a maximum length of 5 minutes, and will be followed by questions. Topics can be based on suggested problems, or on selected topics.

One source of topics might be, the Mechanisms and Mechanical Devices Sourcebook: pgs: 13, 36, 73, 81, 108, 116, 212, 260, 267, 272, 280, 284, 366, 416.

presentations should use overheads or be web based.

presentations should be made as if you are presenting to your peers on a design teams. The presentations don’t need to be elaborate, but they should be enlightening.