Index 891
Motor torque constant, 95
Motorcycle suspension system, 87
Multiple-loop system, 458–59
N
N circles, 480–81
a family of constant, 481
Newton’s second law, 66
Nichols, 2, 11, 398
Nichols chart, 482–85
Nichols plots, 403
Nonbleed-type relay, 111
Nonhomogeneous state equation:
solution of, 666–67
Noninverting amplifier, 79
Nonlinear mathematical models:
linear approximation of, 43–45
Nonlinear system, 43
Nonminimum-phase systems, 300–01,
415, 417
Nonminimum-phase transfer function,
415, 488
Nonuniqueness:
of a set of state variables, 655
Nozzle-flapper amplifier, 110
Number-decibel conversion line, 404
Nyquist, H., 2, 11, 398
Nyquist path, 545
Nyquist plot, 403, 439–40, 443
of positive-feedback system, 535–37
of system defined in state space, 440–43
Nyquist stability analysis, 454–62
Nyquist stability criterion, 445–54
applied to inverse polar plots, 461–62
O
Observability, 675, 682–88
complete, 683–85
matrix, 653
Observable canonical form, 650, 692
Observation, 752
Observed-state feedback control system,
761
Observer, 753
design of control system with, 786–93
full-order, 753
mathematical model of, 752
minimum-order, 767–73
Observer-based controller:
transfer function of, 761
Observer controller:
in the feedback path of control system,
787, 790–93
in the feedforward path of control
system, 787–90
Observer-controller matrix, 762
Observer-controller transfer function,
761–62
Observer error equation, 753
Observer gain matrix, 755
MATLAB determination of, 773
Octave, 405
Offset, 258
On-off control action, 22–23
On-off controller, 22
One-degree-of-freedom control system,
593
op amps, 78
Open-loop control system, 8
advantages of, 9
disadvantages of, 9
Open-loop frequency response curves:
reshaping of, 493
Open-loop transfer function, 19
Operational amplifier, 78
Operational amplifier circuits, 93–94
for lead or lag compensator:
table of, 85
Optimal regulator problem, 806
Ordinary point, 861
Orthogonality:
of root loci and constant gain loci,
301–02
Output controllability, 681
Output equation, 31
Output matrix, 31
Overdamped system, 168–69
Overlapped spool valve, 146
Overlapped valve, 130P
Parallel compensation, 308–09, 342–43
Partial-fraction expansion, 867–73
with MATLAB, 871–73
PD control, 373
PD controller, 614–15
Peak time, 170, 172, 193
Performance index, 793
Performance specifications, 9
Phase crossover frequency, 467–69
Phase margin, 464–67
versuszcurve, 472
PI controller, 2, 614–15
PI-D control, 590–92
PID control system, 572–77, 583, 587,
617–21, 628–29, 642–43
basic, 590
with input filter, 629
two-degrees-of-freedom, 592–95
PID controller, 567, 577, 614–16, 620, 632
modified, 616
using operational amplifiers, 83–84