Machine Design Courses
Many users of my textbooks have requested syllabi, handouts and information on my courses. This note and folder contains information on three courses that I teach at WPI: ME3310-Kinematics of Mechanisms, ME3311-Dynamics of Machinery, and ME3320-Design of Machine Elements. These are Junior level and are each given in a 7-week term with 3 or 4 hours of lecture per week plus 1 or 2 recitation hours per student per week. Each student gets about 5 contact hours a week for a total of 35 hours per term-course. The student is expected to spend at least 15-20 hr./wk outside of class on assignments for each course. Many report (complain) that they spend twice that amount or more on each of these courses.
The kinematics and dynamics courses together give a 14 week exposure to the topics in my book Design of Machinery, McGraw-Hill 3ed, 2004. I cover chapters 1-9 in ME3310-Kinematics (syllabus) and 10-16 in ME3311-Dynamics (syllabus). Thus, the combined syllabi for these two courses can be compared to a regular 14 week -semester offering. I give quizzes but no formal exams in either of these courses, preferring to give open-ended design projects of about 2-weeks duration instead. I assign 3 such projects in ME3310 and two projects in ME3311, one 2-wk and one 4-wk group project. Students are required to keep a contemporaneous design notebook and to document their project work in a professional engineering report according to my supplied report specifications.
The Design of Machine Elements course (ME3320 syllabus) uses my book Machine Design: An Integrated Approach 2ed, Prentice Hall 2002. In 7 weeks I cannot cover anywhere near all the material in this book. I start with Chaps 4, 5 and 6, covering fatigue failure in detail. Then I pick and choose from the elements chapters in the 2nd half of the book based on the character of the term-long design project that I assign, e.g., if it involves shafts, gears and springs, I will lecture on those chapters. I also give weekly quizzes in this course as the one assigned project is a group activity. See syllabus for more detail.
I rely heavily on equation solver solutions and force the students to use either TKSolver or Mathcad for that purpose. All the examples and case studies are done in both Mathcad and TKSolver. These files can be downloaded by professors who have adopted the book Machine Design for a course by registering online.
I realize that this computerized approach to machine design is somewhat controversial, based on feedback from some users of this book, but I strongly believe that it is both necessary and desirable to expose students to as many of these engineering tools that they will have to use in their practice. After all, we no longer use slide rules even though they did reinforce the student’s ability to make engineering estimates and order of magnitude calculations quickly.
My prior and current experience in industry convinces me that we should be using the latest engineering tools with our students. I am not convinced that this takes anything away from a student’s ability to understand the concepts. Quite the contrary, the more the engineering tools do the "scut work" of laborious calculations, the more mental energy the student has to expend on understanding the theory and application of the necessary principles. Also, I can cover much more in the way of realistic and challenging project assignments in the 7 weeks I have available if I unload as much of the busywork from the students as possible.
Included in folders herewith are copies of syllabi for each course and many projects assigned over several past years. The five projects given in sequence in the two courses ME3310 and ME3311 in any year provide a carefully crafted set of increasingly difficult and more structured problems designed to take the student through the design process as described in Chapter 1 of Design of Machinery. This sequence roughly parallels the way a real engineering project progresses, based on my industrial experience.
Project 1 is a very unstructured mechanism design problem involving only position synthesis, and trivial analysis such as DOF, Grashof, transmission angle, etc. (Chaps 1 -3). (cf.: Stroller, Standup, Dumpster, Boatlift) It attempts to force the student to thoroughly define a deliberately ill-stated problem through background research, rediscover his creativity and ideate multiple potential solutions to the redefined problem. This is assigned before any significant analysis topics have been lectured on. No computer programs are needed. This is usually an individual project assignment.
Project 2 is a slightly more structured linkage design and analysis problem that requires the student to both synthesize multiple possible solutions and analyze them for position, velocity, and acceleration. (Chaps 4, 5, 6, 7). (cf.: Grandma2, Tennis, Horseback) Often, human factors are brought in by requiring the device to carry humans at high speeds or accelerations. Programs Fourbar, Fivebar, and Sixbar (included with the text) are used for this project to allow the student to quickly iterate to a viable solution. If conscientiously done this can result in the student attaining an improved understanding of the theory and analytical techniques involved. This is usually an individual project assignment.
Project 3 is a more structured cam design problem and requires use of program Dynacam (included with the text). These projects are often actual industrial problems and allow the student to do some realistic analysis including forces and torques when designing a cam and follower system. (cf.: Cannoli, PBJ, PickPlc1) This is usually a group project assignment.
Project 4 in the sequence (actually Project 1 in ME3311) is similar to project 2 but adds the requirement of force, torque and balancing analysis to the design of a linkage mechanism to solve an unstructured problem. (cf.: Chopper, Antigrav, Paintshk) Minimization of shaking forces and torques is often sought. Program Fourbar and Dynafour are the tools used. This is usually an individual project assignment.
Project 5 in the sequence (actually Project 2 in ME3311) requires the design of some set of IC engines wrt their mechanical dynamics aspects. (cf.: Aircar, Boateng, Outboard) This is quite structured as the desired engine configuration is specified (inline, vee, opposed, etc.) but requires and develops a good understanding of the dynamics topics. This is usually a group project assignment.
The term project in ME3320, Design of Machine Elements, is designed to cover 6 weeks of the 7 week course. It poses a comprehensive design problem such as those outlined in Chapter 8 of the book, Machine Design. That chapter describes actual projects given in this course, some of which are also described herewith. (cf.: Bulbspray, Compress, Cycle.) This is usually a group project assignment.
I hope that this description gives the reader some idea of how my courses are organized. Please see the syllabi and project descriptions attached as well as the report specifications. The latest versions of the programs Fourbar, Fivebar, Sixbar, Slider, Dynacam, Engine and Matrix are also available to instructors who have adopted the book Design of Machinery for a course by registering online.