Dynamics

24-351 Dynamics, 10 units, Fall 2001. URL: http://www.andrew.cmu.edu/course/24-451

Instructor

Professor Qiao Lin
Office: Scaife Hall 217
Phone: 268-3641
Email: qlin@andrew.cmu.edu
Office hours: Thursdays 4:20-6:00pm SH 217

Secretary: Kate McClintock
Office: Scaife Hall 317
Phone: 268-3050
Email: km63@andrew.cmu.edu

Teaching Assistants

Amrinder Nain
Office: Scaife Hall 311
Phone: 268-3658
Email: anain@andrew.cmu.edu
Office hours: Fridays 6:30-8:30pm, HH C101 MechE Computer Cluster

Shahab Shojaeizadeh
Office: Scaife Hall 311
Phone: 268-3658
Email: sshojaei@andrew.cmu.edu
Office hours: Thurdays 7:45-9:45pm, HH C101 MechE Computer Cluster

Grader

Bozhi Yang
Office: HH B127
Phone: 268-8850
Email: bozhi@andrew.cmu.edu

Lectures

Monday and Wednesday, 2:30-3:50 pm, HH B103

Recitations

There are three recitation sections: (A) Friday 10:30 am - 11:20 am, (B) Friday 11:30 am - 12:20 pm, and (C) Friday 12:30 pm - 1:20 pm. Recitation will be held in SH 206. You are expected to attend recitation each week. The recitation will provide an excellent opportunity to get help on the homework, which is due the Monday after recitation.

Course Description

Dynamics is the branch of mechanical engineering that deals with motion and the forces that produce it. 24-351 (10 units) covers: the kinematics of motion in rectangular, polar, and intrinsic coordinates; relative motion analysis with multiple reference frames; planar kinetics through Newton's second law, the work-energy and impulse-momentum methods; motion of engineered systems modeled as particles, systems of particles, and rigid bodies; and free and forced mechanical vibration.

Course Objectives

Through this course you will gain the following skills:

Kinematics: You will be able choose an appropriate coordinate system and analyze the motion - position, velocity, and acceleration - of the parts of a device.
Equations of Motion: You will be able to derive the equations of motion for a system using the direct momentum method, the work-energy method, and the impulse-momentum method.
Modeling: You will gain the ability to transform a physical system into a mathematical representation, allowing you to accurately predict the system?s behavior.
Graphical Techniques: You will learn how to use a variety of graphical representations that greatly facilitate the solution of dynamics problems including free-body diagrams, kinetic diagrams, and vector polygons.
Computing Skills: You will learn how to use computational tools to solve dynamics problems.

Prerequisites

33-106: Physics for Engineering Students I
24-261: Statics
21-259: Calculus in Three Dimensions, which may be taken concurrently

Required Text

Reading and problems will be assigned each week from: R. C. Hibbeler, Engineering Mechanics: Dynamics, Ninth edition, Prentice-Hall, 2001. Also, quiz problems will usually be taken from the problems in the text.

References

The required textbook will be generally adequate for the purpose of this course. However, for those who wish to pursue additional reading, the following books have been placed on reserve in the Engineering and Science (E&S) Library, which is located on the fourth floor of Wean Hall:

F.P. Beer and E.R. Johnston, Vector Mechanics for Engineers: Statics and Dynamics, Fifth edition, McGraw Hill.
D.J. McGill and W.W. King, Engineering Mechanics: an Introduction to Dynamics, Third edition, PWS Publishing.
J.L. Meriam and L.G. Kraige, Engineering Mechanics: Dynamics, Fourth edition, Wiley.
W.F. Riley and L.D. Sturges, Engineering Mechanics: Dynamics, Second edition, Wiley.
A. Bedford and W. Fowler, Engineering Mechanics: Dynamics, Addison-Wesley.

Software

Adams is a commercial dynamic simulation package that is widely used in industry. Some of your homework problems will require the use of this software. Adams will allow you to explore problems that would be too complicated or time consuming to solve by hand. As a side-benefit, you will gain experience that is highly sought-after in industry. Adams is available in the Mechanical Engineering cluster in HH C101. There are a limited number of machines (currently 17), and thus the cluster may be full the night before the homework is due. You should start on the Adams homework problems early to ensure that you get access to a computer.

Here is an online tutorial for Adams that will allow you to get started with the software. Additional online tutorials will be available soon.

Homework Schedule and Policy

Homework will be assigned every Monday and will be due the following Monday in class. Graded homework will be returned the Friday following the due date. Students are encouraged to discuss assignments, but material submitted for grading must be the product of individual effort.

Requests for homework extensions are considered only if they are received by the instructor via email BEFORE the due date. Do not attempt to obtain an extension on or after a due date. If an extension is granted by the instructor, a note indicating the amount of the extension should be turned in lieu of the homework on the normal due date. In addition, this same information should be attached to the homework when it is eventually turned in.

Homework turned in late without an extension granted by the instructor will incur the following grade reductions:

up to one day - a 5% grade reduction
two days late - a 10% grade reduction
three days late - a 20% grade reduction
four days late - a 40% grade reduction
five days late - an 80% grade reduction
six or more days late - a grade of zero will be given

Quizzes and Exams

Each week, at the beginning of the Monday class, there will be a quiz with one problem that lasts approximately 20-30 minutes. Each quiz will cover the same material as the homework assignment that is graded and returned the previous Friday. However, it should be noted that the quiz and homework problems may be significantly different in the way they are posed. The quizzes will be closed-book and closed-note. While numerical calculations involved in the quizzes will generally be minimal, it is recommended that you bring a caculator. There will be no quizzes on:

August 27, and September 3 and 10 (first three weeks of class)
October 22 (Mid-Semester Break)
November 26 (week following Thanksgiving)
December 10 (last day of class for this course)

Requests for make-up quizzes will be considered in the event of illness or emergency. However, if possible, you must notify the instructor in advance. If you are sick, a note from the student health center is required. If you are on a CMU sports team, check your schedule now so that we can make arrangements for quizzes that will be missed due to away games. If there is a special (reasonable) circumstance that will cause you to miss a quiz, contact the instructor in advance to make arrangements. A quiz otherwise missed will receive a grade of zero.

There will be no midterm and final exams for this course.

Grading

Homework assignments will account for 40% and quizzes 60% in calculating the course grade. One (lowest) quiz score and one (lowest) homework score will be dropped from the calculations. The course grade will be given on the following absolute scale:

85-100 A
75-84   B
65-74   C
55-64   D
0-54     R

Feedback

Every group of students has a different technical background. Some things that you find easy, previous classes may have had trouble with, and vice versa. The best way to handle this is to give the instructor feedback. If there are things that don't make sense, ask questions. If the pace of the course seems too fast or too slow, let us know. If you don't tell us, homework and quizzes are the only means we have to judge how well the material matches your needs. You can help us, and yourselves, by giving us lots of feedback on all aspects of the course. Ask questions in lecture and recitation. Talk to the instructor or the TAs after class or during office hours. Send email. Drop a note. Use whatever means you find comfortable! We take your feedback very seriously. If you let us know about an issue, we will do everything possible to remedy it.