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ABSTRACT: The problem of discrete-time adaptive stabilization under full-state feedback control is considered under weaker assumptions than the prior literature. The main result is based on a gain update law involving a step-size function. The formulation generalizes and unifies prior results based on quadratic and logarithmic Lyapunov functions.
American Control Conference, 2003. Proceedings of the 2003; 07/2003
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ABSTRACT: In this paper we present a numerical and experimental
investigation of the properties of the ARMARKOV adaptive control (AAC)
algorithm with simultaneous identification. The underlying model
structure of AAC is the ARMARKOV model, which is a structurally
constrained ARMA model with explicit impulse response (Markov)
parameters. This algorithm requires a model of only the secondary path
(control input to performance variable) transfer function which is
identified online using the time-domain ARMARKOV/Toeplitz identification
technique. For a 5-mode acoustic duct model, we present numerical as
well as experimental results for single-tone, dual-tone, and broadband
disturbance rejection. In the simulations and experiments we assume no
knowledge of the disturbance signal
IEEE Transactions on Control Systems Technology 02/2001; · 1.77 Impact Factor
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ABSTRACT: An adaptive disturbance rejection algorithm is developed for the
standard control problem. The multiple input-multiple output (MIMO)
system and controller are represented as ARMARKOV/Toeplitz models, and
the parameter matrix of the compensator is updated online by means of a
gradient algorithm. The algorithm requires minimal knowledge of the
plant, specifically, the numerator of the ARMARKOV model of the transfer
function from the control inputs to the performance variables is
required. No knowledge about the spectrum of the disturbance is needed.
Experimental results demonstrating tonal and broadband disturbance
rejection in an acoustic duct are presented
IEEE Transactions on Control Systems Technology 04/2000; · 1.77 Impact Factor
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ABSTRACT: We perform numerical experiments involving the ARMARKOV adaptive
control algorithm. The performance of the algorithm is considered under
a diverse set of conditions representing plant and disturbance
uncertainty including perturbed disturbance spectrum, perturbed plant
model, additive measurement noise, control input saturation, and
feedback path sign inversion. These numerical experiments can be viewed
as only representative illustrations of the properties of this adaptive
control algorithm. Nevertheless, these simulations suggest that the
algorithm has significant ability to provide robust stability and
performance under diverse deteriorating conditions
American Control Conference, 1999. Proceedings of the 1999; 02/1999
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ABSTRACT: Karplus and Strong (1983) proposed a highly successful algorithm
for digital music synthesis. In this paper we describe this algorithm in
terms of a linear transfer function. Then we propose several extensions
and variations of this transfer function that produce interesting
synthetic musical sounds. The work is guided by experimental production
of the sounds and provides a satisfying application of linear systems
theory
American Control Conference, 1999. Proceedings of the 1999; 02/1999
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ABSTRACT: Active control of thermo-acoustic instabilities represents a
significant challenge and opportunity for feedback control technology.
In this paper, we experimentally apply ARMARKOV adaptive control to a
ducted flame with a servovalve actuator. This approach requires an
identified model of the transfer function from the control input
(modulated air stream) to the performance variable (microphone). This
identification was performed under fuel-burning conditions. No
analytical modeling was used for controller analysis or synthesis. The
ARMARKOV adaptive controller suppressed the fundamental component of the
limit cycle oscillation
Decision and Control, 1998. Proceedings of the 37th IEEE Conference on; 01/1999
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ABSTRACT: An adaptive algorithm is developed for the MIMO tracking problem.
The MIMO system and controller are represented as ARMARKOV/Toeplitz
models, and the parameter matrix of the compensator is updated online by
means of a gradient algorithm. The algorithm does not require any
knowledge of the plant. Simulation results on a fourth order system are
presented
American Control Conference, 1998. Proceedings of the 1998; 07/1998
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ABSTRACT: An adaptive disturbance rejection algorithm is developed for the
standard control problem. The MIMO system and controller are represented
as ARMARKOV/Toeplitz models, and the parameter matrix of the compensator
is updated online by means of a gradient algorithm. The algorithm
requires minimal knowledge of the plant, specifically, the numerator of
the ARMARKOV transfer function from control to performance is required.
No knowledge about the spectrum of the disturbance is needed.
Experimental results demonstrating tonal and broadband disturbance
rejection in an acoustic duct are presented
Decision and Control, 1997., Proceedings of the 36th IEEE Conference on; 01/1998
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ABSTRACT: With the success of adaptive cancellation methods developed largely within the active noise control community, it is of interest to understand these algorithms within a more traditional feedback control framework. This paper thus has two goals, namely, to systematically describe three such algorithms (two LMS algorithms and the recently developed ARMARKOV/Toeplitz algorithm) in standard feedback control terminology, and to experimentally compare the performance of the algorithms. For experimental purposes, we use an acoustic duct testbed with both tonal and broadband disturbances.
Control Applications, 1997., Proceedings of the 1997 IEEE International Conference on; 11/1997
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ABSTRACT: We develop an adaptive disturbance rejection algorithm formulated
in terms of an AR-MARKOV/Toeplitz matrix system representation. The
algorithm is applied to the problem of active noise suppression in an
acoustic duct, and experimental results demonstrating tonal and
broadband disturbance rejection are presented
American Control Conference, 1997. Proceedings of the 1997; 07/1997
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ABSTRACT: The wave motion of fluids in finite containers, called slosh, is
known to have adverse effects on the dynamics of aerospace vehicles and
tanker trucks as well as on large storage tanks during earthquakes. This
paper investigates slosh from an active feedback control perspective,
and considers two possible active control methods for attenuating the
response of the fluid to an external disturbance acceleration acting on
the tank. The first method uses surface pressure control, whereas the
second method uses a flap actuator on the surface of the fluid. In the
first part of the paper we derive a state space model of slosh in a tank
of rectangular cross section. This model is then used to design feedback
controllers using LQG synthesis, and simulation results are presented to
demonstrate the closed-loop performance
Control Applications, 1996., Proceedings of the 1996 IEEE International Conference on; 10/1996
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ABSTRACT: This paper develops a state space model of an acoustic duct with
end-mounted speakers. The initial model formulation introduces the
forcing term as a boundary condition. The shifted particle velocity is
then defined to transform the nonhomogeneous boundary condition to a
homogeneous boundary condition and thus develop the state space model.
It is shown that the speaker and acoustic duct interact by means of
feedback in which the speaker creates an acoustic field, which, in turn,
affects the motion of the speaker baffle. The interaction between the
speaker and acoustic dynamics is studied using positive real closed-loop
feedback analysis, and shifts in the modal frequencies of the duct due
to the presence of the end-mounted speaker are predicted
Control Applications, 1996., Proceedings of the 1996 IEEE International Conference on; 10/1996
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ABSTRACT: Although active noise control has been a subject of interest for
over 50 years, it has become feasible only with recent technological
advances. This paper formulates the problem of noise control in a
one-dimensional acoustic duct in a form that lends itself to the
application of feedback control theory. In contrast to most of the
literature on the subject which uses feedforward techniques, a feedback
approach is used. Inconsistencies that appear in previous feedback
control models are rectified, controllers are designed using
precompensated linear quadratic Gaussian (LQG) synthesis, and
experimental verification of the control designs is presented. The
experimental results show a reduction of about 5-12 dB over a frequency
range from 150-350 Hz
IEEE Transactions on Control Systems Technology 06/1996; · 1.77 Impact Factor
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ABSTRACT: We consider a single-input, single-output plant involving one
control actuator (speaker) and one control sensor (microphone).
Additional speakers and microphones are used to provide disturbances and
to assess closed-loop performance. To simplify matters, we confine our
consideration in this paper to the case of a collocated sensor and
actuator, that is, the control speaker and control microphone located at
the same position along the duct. This configuration has been studied in
the noise control literature under the name of tightly coupled monopole.
In designing feedback controllers for the acoustic duct, we apply modern
state space control techniques. The use of such techniques is
necessitated by the high order of the identified model, which, for a 400
Hz modeling bandwidth in our experiment, involves 30 states. Feedback
controllers designed for noise suppression were obtained by applying LQG
synthesis with suitable precompensation to assure robustness to high
frequency uncertainty
American Control Conference, 1995. Proceedings of the; 07/1995
