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Chapter 7: Steady-State Errors1
Chapter 7
Steady-State Errors
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Chapter 7: Steady-State Errors2
Table 7.1Test waveforms for evaluating steady-state errors of position control systems
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Chapter 7: Steady-State Errors3
Figure 7.1Test inputs for steady-state error analysis and design vary with target type
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Chapter 7: Steady-State Errors4
Figure 7.2Steady-state error:a. step input;b. ramp input
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Chapter 7: Steady-State Errors5
Figure 7.3Closed-loop controlsystem error:a. general representation;b. representation forunity feedback systems
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Chapter 7: Steady-State Errors6
Figure 7.4System with:a. finite steady-stateerror for a step input;b. zero steady-stateerror for step input
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Chapter 7: Steady-State Errors7
Figure 7.5Feedbackcontrol system forExample 7.2
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Chapter 7: Steady-State Errors8
Figure 7.6Feedbackcontrol system forExample 7.3
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Chapter 7: Steady-State Errors9
Figure 7.7Feedbackcontrol systems forExample 7.4
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Chapter 7: Steady-State Errors10
Figure 7.8Feedback controlsystem for definingsystem type
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Chapter 7: Steady-State Errors11
Table 7.2Relationships between input, system type, static error constants, and steady-state errors
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Chapter 7: Steady-State Errors12
Figure 7.9A robot used inthe manufacturingof semiconductorrandom-accessmemories (RAMs)similar to those inpersonal computers.Steady-state error is an important design consideration for assembly-line robots.
© Westlight/ Charles O’Rear.
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Chapter 7: Steady-State Errors13
Figure 7.10Feedbackcontrol systemfor Example 7.6
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Chapter 7: Steady-State Errors14
Figure 7.11Feedback controlsystem showingdisturbance
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Chapter 7: Steady-State Errors15
Figure 7.12Figure 7.11 systemrearranged to showdisturbance as input and error as output,with R(s) = 0
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Chapter 7: Steady-State Errors16
Figure 7.13Feedback control system for Example 7.7
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Chapter 7: Steady-State Errors17
Figure 7.14System forSkill-AssessmentExercise 7.4
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Chapter 7: Steady-State Errors18
Figure 7.15Forming an equivalentunity feedbacksystem from ageneral nonunity feedback system
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Chapter 7: Steady-State Errors19
Figure 7.16Nonunity feedbackcontrol system forExample 7.8
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Chapter 7: Steady-State Errors20
Figure 7.17Nonunity feedbackcontrol system withdisturbance
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Chapter 7: Steady-State Errors21
Figure 7.18Nonunity feedbacksystem forSkill-AssessmentExercise 7.5
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Chapter 7: Steady-State Errors22
Figure 7.19Feedback controlsystem for Examples7.10 and 7.11
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Chapter 7: Steady-State Errors23
Figure 7.20Feedbackcontrol systemfor Example 7.12
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Chapter 7: Steady-State Errors24
Figure 7.21System forSkill-AssessmentExercise 7.6
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Chapter 7: Steady-State Errors25
Figure 7.22Video laser discrecording:control system forfocusing write beam
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Chapter 7: Steady-State Errors26
Figure 7.23Video disc laserrecording:a. focus detectoroptics;b. linearized transfer function for focus detector
© 1985, Prentice Hall, Inc.
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Nise/Control Systems Engineering, 3/e
Chapter 7: Steady-State Errors27
Figure 7.24Video laser discrecording focusingsystem
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Chapter 7: Steady-State Errors28
Figure P7.1
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Chapter 7: Steady-State Errors29
Figure P7.2
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Chapter 7: Steady-State Errors30
Figure P7.3
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Chapter 7: Steady-State Errors31
Figure P7.4
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Chapter 7: Steady-State Errors32
Table P7.1
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Chapter 7: Steady-State Errors33
Figure P7.5
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Chapter 7: Steady-State Errors34
Figure P7.6
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Chapter 7: Steady-State Errors35
Figure P7.7
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Chapter 7: Steady-State Errors36
Figure P7.8
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Chapter 7: Steady-State Errors37
Figure P7.9
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Chapter 7: Steady-State Errors38
Figure P7.10
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Chapter 7: Steady-State Errors39
Figure P7.11
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Chapter 7: Steady-State Errors40
Figure P7.12
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Chapter 7: Steady-State Errors41
Figure P7.13Closed-loop systems withnonunityfeedback
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Chapter 7: Steady-State Errors42
Figure P7.14
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Chapter 7: Steady-State Errors43
Figure P7.15
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Chapter 7: Steady-State Errors44
Figure P7.16
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Chapter 7: Steady-State Errors45
Figure P7.17
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Chapter 7: Steady-State Errors46
Figure P7.18System with input anddisturbance
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Chapter 7: Steady-State Errors47
Figure P7.19
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Chapter 7: Steady-State Errors48
Figure P7.20System with input anddisturbance
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Chapter 7: Steady-State Errors49
Figure P7.21Automobile guidance systema. displacementcontrol system;b. velocity control loop
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Chapter 7: Steady-State Errors50
Figure P7.22Block diagram of aparamagnetic oxygenanalyzer
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Chapter 7: Steady-State Errors51
Figure P7.23Space station Freedom:a. configuration(figure continues)
© 1992 AIAA.
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Chapter 7: Steady-State Errors52
Figure P7.23(continued)b. simplified blockdiagramc. alpha joint drivetrain and controlsystem
© 1992 AIAA.
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Chapter 7: Steady-State Errors53
Figure P7.24Position controlsystem
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Chapter 7: Steady-State Errors54
Figure P7.25Boat trackedby ship’s radar:a. physicalarrangement;b. block diagram of tracking system
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Chapter 7: Steady-State Errors55
Figure P7.26Simplified blockdiagram of a pilot ina loop
© 1992 AIAA.
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Chapter 7: Steady-State Errors56
Figure P7.27a. Force controlmechanical loopunder contact motion(©1996 IEEE);b. block diagram(©1996 IEEE)
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Chapter 7: Steady-State Errors57
Table 7.1Test waveforms for evaluating steady-state errors of position control systems
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Chapter 7: Steady-State Errors58
Table 7.2Relationships between input, system type, static error constants, and steady-state errors
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Chapter 7: Steady-State Errors59
Table P7.1