Mass Soil Movements in the H. J. Andrews Experimental Forest

849 Pages·2018·20.09 MB·English

by  Dyrness, C T

Pearson New International Edition

Kinematics and Dynamics of Machinery

Charles E. Wilson J. Peter Sadler
Third Edition
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ISBN 10: 1-292-04005-X
ISBN 13: 978-1-292-04005-9
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ISBN 10: 1-292-04005-X
ISBN 10: 1-269-37450-8
ISBN 13: 978-1-292-04005-9
ISBN 13: 978-1-269-37450-7
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P E A R S O N C U S T O M L I B R AR Y
Table of Contents
Symbols
Charles E. Wilson, J. Peter Sadler 1
Chapter 1. Mechanisms and Machines: Basic Concepts. 
Charles E. Wilson, J. Peter Sadler 5
 Chapter 2. Motion in Machinery. 
Charles E. Wilson, J. Peter Sadler 103
 Chapter 3. Velocity Analysis of Planar and Spatial Mechanisms. 
Charles E. Wilson, J. Peter Sadler 165
 Chapter 4. Acceleration Analysis of Planar and Spatial Mechanisms. 
Charles E. Wilson, J. Peter Sadler 264
 Chapter 5. Design and Analysis of Cam and Follower Systems. 
Charles E. Wilson, J. Peter Sadler 339
 Chapter 6. Spur Gears: Design and Analysis. 
Charles E. Wilson, J. Peter Sadler 405
 Chapter 7. Helical, Worm, and Bevel Gears: Design and Analysis. 
Charles E. Wilson, J. Peter Sadler 471
 Chapter 8. Drive Trains: Design and Analysis. 
Charles E. Wilson, J. Peter Sadler 515
 Chapter 9. Static-Force Analysis. 
Charles E. Wilson, J. Peter Sadler 613
Chapter 10. Dynamic-Force Analysis. 
Charles E. Wilson, J. Peter Sadler 689
Chapter 11. Synthesis. 
Charles E. Wilson, J. Peter Sadler 779
Partial Answers to Selected Problems
Charles E. Wilson, J. Peter Sadler 821
Index 837
I
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Symbols
Vectors and matrices are shown in boldface,scalar magnitudes in lightface.
A-1 Inverse of matrix A hp Horsepower
#
A B Dot (scalar) product of vectors Aand B I Mass moment of inertia
A * B Cross (vector) product of vectors Aand B i,j,k Cartesian unit vectors
a Gear tooth addendum j Cam follower jerk;1-1,the imaginary
unit used to represent quantities on the
a,a Acceleration
complex plane
ac, ac Coriolis acceleration
L Link length,sound level
an, an Normal acceleration
L Length of diagonal (of linkage polygon)
at, at Tangential acceleration d
l Lead of worm
bc Velocity of Crelative to B(velocity
difference) li Length of link i
C Cylinder pair;planet carrier Ms Shaking moment
C Force couple m Mass;module;slope;meters
C Inertia couple or inertia torque mn Normal module
i
c Center distance N Number of gear teeth;newtons
CAD Computer-aided design N Normal force
D Determinant n Rotational speed (revolutions per minute)
d Diameter of pitch circle nc Number of constraints
db Diameter of base circle nJ Number of joints
DF Degrees of freedom nL Number of links
e Instantaneous efficiency;cam-follower O1 Fixed bearing on link 1
offset;piston offset;eccentricity ob Absolute velocity of point B
eju Polar form of a complexnumber P Prism pair;planet gear;power;diametral
F Force pitch
F Axial or thrust gear tooth force component P Piston force
a
F External force Pn Normal diametral pitch
e
F Inertia force i P Position vector in frame i
i 5 6
F Force exerted by a member ion member j p Transverse circular pitch,pressure
ij
F Normal gear tooth force p Base pitch
n b
F Radial gear tooth force component pn Normal circular pitch
r
F Shaking force p Axial pitch of worm
s w
F Tangential gear tooth force component R Revolute pair;ring gear;length of crank
t
f frequency R Position vector
f Joint connectivity i[R] Rotational transformation matrix
i j
G Center of mass r Radius of pitch circle
H Helix pair r Position vector;vector representing a link
#
h Cam follower lift r Derivative of rwith respect to time
From Kinematics and Dynamics of Machinery, Third Edition. Charles E. Wilson, J. Peter Sadler.
Copyright © 2003 by Pearson Education, Inc. All rights reserved.
1
Symbols xxvii
r… Train value (speed ratio) for a planetary x,y,z Cartesian coordinates
train relative to the carrier * Cross product
ra Length of cam-follower arm; radius of a, A Angular acceleration
addendum circle
a Cam rotation angle;angle of approach
r Base circle radius; radius of back cone
b b Angle of recess
element
≠ Pitch angle
r Center distance between cam and fol-
c g Cam follower rotation;pitch angle;mass
lower pivots
density
r Radius of cam-follower roller;radius of
f df, dx Virtual displacements
friction circle
u Angular position of link;cam angle;
r Mean pitch radius
m
angle of action;connecting rod angle
r Velocity ratio
v
u Angular position of link i
ru Unit vector i
u Angular spacing of engine cylinders;
r xcomponent of vector r n
x joint angle about axis n
S Sphere pair;sun gear
l Lead angle of worm
s,s Displacement
m Coefficient of sliding friction
s Seconds
r Radius of curvature
s Axial spacing of engine cranks and cylin-
n
r Radius of curvature of pitch curve
ders;joint offset along axis n p
T,T Torque © Angle between shafts
Te External torque ti Link twist of member i
i[T] Transformation matrix from frame j to £ Heaviside step function
j
frame i f Transmission angle;pressure angle;
t Time;gear tooth thickness transverse pressure angle;friction angle
U Universal joint fi Angular position of link i
v Velocity fn Normal pressure angle
v Pitch line velocity c Involute angle;helix angle
p
W Work;watts c Angular spacing of engine cranks
n
w Gear tooth width;weight v, V Angular velocity
What You Will Learn and Apply in the Study of the Kinematics and
Dynamics of Machinery
The following is a partial list of the knowledge and skills you will acquire or enhance.In many
cases,you will be applying mathematics and scientific principles that you learned previously.
• Effective computer use an software selection
• Application of animation software to linkage design
• Application of mathematics software to mechanism design
• Computer-aided solutions to engineering problems using vector and matrix equations
• Mobility of planar and spatial linkages
• Determination of motion characteristics of linkages
• Design to avoid binding and interference
• Design and selection of mechanisms for specific applications
2
xxviii Symbols
• Analytical vector methods applied to linkage design
• Complex number methods applied to linkage design
• Analytical and graphical methods for finding linkage velocities
• Analytical and graphical methods for finding linkage accelerations
• Design and analysis of cams
• Design and analysis of spur gears
• Design and analysis of helical,worm,and bevel gears
• Arrangement of gears to produce desired input–output speed ratios
• Design of planetary speed changers
• Analysis of static forces in linkages and gear and cam mechanisms
• Analysis of dynamic forces in linkages
• Balancing of rotors and reciprocating machines
• Synthesis of linkages to produce predetermined motion
• Design and analysis of simple robotic manipulators
• Critical thinking applied to mechanism design.Critical thinking involves identification
of a problem,gathering of data,objective analysis,and an attempt at solving the prob-
lem by a scientific process.This skill should be honed throughout an engineer’s educa-
tion and practice.
• Engineering creativity.The text and problems are designed to foster creativity,but this
goal depends almost entirely on the student (with encouragement from an instructor).
3
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C H A P T E R 1
Mechanisms and Machines:
Basic Concepts
In this chapter,you will learn
• The terms we use to describe mechanisms
• The degrees of freedom of mechanisms
• How to design crank-rocker,double-rocker,drag link,and other mechanisms
• How to design linkages to prevent jamming and interference
• How to optimize a mechanism design
• Computer animation of linkages to check the validity of a design
• The design of quick-return mechanisms
• The design and selection of mechanisms for special applications
• Numerical solutions
• Other basic concepts.
Kinematics and dynamics are vital components of machine design.An understanding
of the kinematics and dynamics of machinery is important to the design of
• Production machinery,including robots and other programmable machines
• Consumer goods and office machines
• Aircraft and surface transportation vehicles
• Agricultural and construction machinery
• Many other items considered essential to modern living
1.1 INTRODUCTION
Kinematics and dynamics of machineryinvolve the design of machines on the basis of
their motion requirements. A combination of interrelated parts having definite
motions and capable of performing useful work may be called a machine.A mecha-
nism is a component of a machine consisting of two or more bodies arranged so that
From Chapter 1 of Kinematics and Dynamics of Machinery, Third Edition. Charles E. Wilson, J. Peter Sadler.
Copyright © 2003 by Pearson Education, Inc. All rights reserved.
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