Theory of Mechanism and Machines I

Course Objectives:
To make students understand about different mechanism used in devices or machines and make them able to do complete analysis of mechanism (including linkages, gears,  gear trains,  cams and followers).

Course Outlines:

1. Introduction(2 hours)
1. Introduction to the study of mechanisms
2. Basic definitions  & descriptions
3. Mechanism configurations, links, chains, inversions
4. Transmission of motion
5. Mobility, Degree of freedom


2. Linkages and Mechanisms(4 hours)
1. Position Analysis of the four-bar mechanism
2. Four-bar linkage motion and Grashoff’s law
3. Linkage position analysis; loop closure equations & iterative methods
4. Introduction to different mechanism :  Slider crank, Scotch Yoke,Quick return,toggle,Oldham coupling & Hooke’s Coupling, Straight line,  Chamber wheel,constant velocity universal joint, intermittent motion,  mechanical computing, etc. mechanisms.
5. Synthesis concepts


3. Cams and Followers(6 hours)
1. Classification of cams and nomenclature
2. Graphical cam layout;
3. Disk cam with flat-faced follower
4. Disk cam with Radial or Offset follower
5. Standardized Follower Displacement  or Lift curves
6. Analytical Cam Design; Disk cam with flat-faced follower: Disk cam with Radial or Offset follower: Disc cam with Oscillating Roller follower
7. Other cam layouts
8. Cam production methods


4. Spur Gears (6 hours)
1. Introduction to Involute spur gears
2. Geometry of Involutes
3. Characteristics of Involute Tooth Action
4. Standardization of Gears; Metric system
5. Interference of Involute Gears
6. Numbers of teeth to avoid interference
7. Determining backlash in  Involute gears
8. Non-standard Spur gears; extended center distance system
9. Methods of gear production


5. Bevel, Helical and Worm Gears(5 hours)
1. Theory of straight Bevel gears
2. Bevel Gear  tooth proportions and geometrical details
3. Spiral and Hypoid gears
4. Theory of helical gears & tooth geometry
5. Parallel and crossed shafts for helical gears
6. Worm gearing


6. Simple and Planetary gear trains (5 hours)
1. Theory of Planetary Gear Trains
2. Speed Ratios; Formula and Tabular Methods
3. Applications
4. Assembly of Planetary gear trains


7. Kinematic Analysis of Mechanisms(9 hours)
1. General Plane Motion Representation
2. Relative Motion Velocity Analysis; Velocity Polygons; Graphical or Vector algebra solutions
3. Instantaneous centers of velocity
4. Kennedy’s theorem
5. Velocities by Instantaneous centers
6. Relative motion acceleration analysis; Acceleration Polygons; Graphical or Vector algebra solutions; Corilis acceleration applications
7. Motion analysis by vector mathematics; Velocity analysis, Acceleration Analysis, Coriolis Acceleration Application
8. Analysis by Complex Numbers;  Loop Closure Equation for Geometrical Layout,  Kinematic Analysis by Complex Numbers Application


8. Force Analysis of Mechanisms(8 hours)
1. Centrifugal Force,  Inertia Force and Inertia Torque
2. Methods of Force Analysis – Introduction
3. Forces on Gear Teeth- spur/bevel &  helical gears
4. Force analysis on cams & followers
5. Superposition Force Analysis Methods,  Graphical or Analytical
6. Linkage Force by Matrix Methods
7. Linkage Force by Method of Virtual Work
8. Linkage Force by  Complex Number Method
9. Applications and Examples

References:

1. H.H. Mabie and C. F. Reinholtz, “ Mechanism and  Dynamics of Machinery”, Wiley. ( Latest in 2011)
2. Mechanisms and machine theory- J.S. Rao & R.V. Dukkipati (Latest in 2011)
3. J.E. Shigley and J.J. Uicker, Jr., “ Theory of Machines and Mechanisms”, McGraw Hill, ( Latest in 2011)
4. Text  Book  of  “ Theory of Machines  and  Mechanisms”  J.S.  Rao &
5. B. PauSl, “Kinematics and Dynamics of Planar Machinery”, Prentice Hall, (Latest in 2011)
6. C. E. Wilson, J.P. Sadler and W.J. Michels.  “ Kenematics and Dynamics of Machinery”, Harper Row, (Latest in 2011)

Evaluation Scheme:
There will be questions covering all the chapters of the syllabus. The evaluation scheme for the questions will be as indicated in the table below: