Supervisory cascaded controller design: experiment test on a remotely operated vehicle

The article proposes a cascaded multi-controllers switching scheme for stabilization and pipeline tracking of a remotely operated vehicle (ROV) under hydrodynamic uncertainties. The ROV is inherently non-linear, highly coupled in motions, and vulnerable to hydrodynamic uncertainties. With controllers that cancel the non-linear dynamics, the system is robust against the pre-defined perturbations on the hydrodynamic added mass and the damping terms. The values used in these perturbed terms were obtained numerically using the WAMITTM software. Compared with other controllers such as proportional-integral and backstepping methods, the pool test showed that the proposed method gives better time domain response and robustness against the perturbed terms.

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Conceptual Analysis of the Non-Linear Forced Response of Aerodynamically Unstable Bladed-Discs

Volume 7A: Structures and Dynamics ◽

10.1115/gt2013-94851 ◽

2013 ◽

Cited By ~ 3

Author(s):

Roque Corral ◽

Juan Manuel Gallardo ◽

Rahul Ivaturi

Keyword(s):

Time Domain ◽

Linear Response ◽

Harmonic Excitation ◽

Friction Model ◽

Forced Response ◽

Response Analysis ◽

Non Linear ◽

Aerodynamic Instability ◽

Time Domain Response ◽

The Time Domain

The response of aerodynamically unstable tuned bladed-discs with non-linear friction dissipation at blade-root attachments due to harmonic external excitation is studied. The bladed-disc is modeled using a simple mass-spring system and the effect of friction is modeled using a micro-slip friction model. The response is computed in time domain using a Runge-Kutta scheme. The time domain response is decomposed to obtain the evolution of traveling waves in the bladed-disc. Parametric studies have been conducted to study the non-linear response at different vibration amplitudes at high and low engine orders of excitation. It is seen that the non-linearity due to friction gives rise to a complicated interaction between the synchronous response of the system due to harmonic excitation and the non-synchronous response of the system due to aerodynamic instability. For low excitation levels the system behaves as in the pure flutter regime where a single, or at most a few, aerodynamically unstable modes may be found in the final state when a limit cycle is reached. When the forcing is large enough the aerodynamic instability is suppressed and only the non-linear response of the excited mode may be seen. It is concluded that the superimposition of the flutter and forced response analysis in terms of vibration amplitude is not valid and leads to prediction of vibration amplitudes significantly larger than that obtained when both phenomena are simulated together.

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Novel Non-Linear Transient Path Energy Method for the Analytical Analysis of the Non-Periodic and Non-Linear Dynamics of Electrical Machines in the Time Domain

IEEE Access ◽

10.1109/access.2019.2905856 ◽

2019 ◽

Vol 7 ◽

pp. 37833-37854 ◽

Cited By ~ 5

Author(s):

Nikita Gabdullin ◽

Jong-Suk Ro

Keyword(s):

Time Domain ◽

Energy Method ◽

Electrical Machines ◽

Linear Dynamics ◽

Analytical Analysis ◽

Non Linear ◽

The Time Domain

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Active Vibration Suppression Control Algorithm in Gyroscopic System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.2490 ◽

2010 ◽

Vol 139-141 ◽

pp. 2490-2493

Author(s):

Zhi Huan Zhang ◽

Sultan A.Q. Siddiqui

Keyword(s):

Strong Coupling ◽

Control Algorithm ◽

Natural Frequencies ◽

Vibration Suppression ◽

Control Method ◽

Controller Design ◽

Gyroscopic System ◽

Linear Dynamics ◽

Linear Coupling ◽

Non Linear

A new control method for suppressing vibration in a rotating beam system of a helicopter has been presented. The method used a non-linear dynamics equation to compute actual natural frequencies using FFT, not based on nominal natural frequencies of linear dynamics. A design based on linear coupling may not take account of the effect of non-linear coupling in the system, so a conceptual controller design has also been presented, and a detailed control algorithm has been developed. In fact, this is a non-linear dynamics optimization problem. In a gyroscopic system, tuning of the flywheel allows a commensurable relationship to be established between the natural frequencies of the system, resulting in a strong coupling between the vibrating modes. Having established a strong coupling within the system, damping was introduced in the flywheel via an actuator, resulting in rapid vibration suppression. Numerical simulation demonstrated the efficiency of the modification.

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Non-Linear Dynamics And The Biological Basis Of Neglect And Attachment Behaviors

PsycEXTRA Dataset ◽

10.1037/e627982011-001 ◽

2000 ◽

Author(s):

Susan Mirow

Keyword(s):

Linear Dynamics ◽

Biological Basis ◽

Non Linear

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Low pressure hydrocephalus and ventriculomegaly: hysteresis, non-linear dynamics, and the benefits of CSF diversion

British Journal of Neurosurgery ◽

10.3109/02688690209168360 ◽

2002 ◽

Vol 16 (6) ◽

pp. 555-561 ◽

Cited By ~ 12

Author(s):

M. S. Lesniak ◽

R. E. Clatterbuck ◽

D. Rigamonti ◽

M. A. Williams

Keyword(s):

Low Pressure ◽

Linear Dynamics ◽

Non Linear ◽

Csf Diversion

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Forecasting Cnx-500 Index: Using Non-Linear Dynamics Threshold Model

SSRN Electronic Journal ◽

10.2139/ssrn.2618428 ◽

2015 ◽

Author(s):

Nishant Vats ◽

Rudra Prakash Pradhan

Keyword(s):

Threshold Model ◽

Linear Dynamics ◽

Non Linear

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Non-linear dynamics in DIS at NLO

10.22323/1.297.0066 ◽

2017 ◽

Author(s):

Giovanni Antonio Chirilli

Keyword(s):

Linear Dynamics ◽

Non Linear

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Non-Linear Dynamics and Endogenous Cycles

10.1007/978-3-642-58901-0 ◽

1998 ◽

Cited By ~ 1

Keyword(s):

Linear Dynamics ◽

Endogenous Cycles ◽

Non Linear

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A novel LSSVM-L Hammerstein model structure for system identification and nonlinear model predictive control of CSTR servo and regulatory control

Chemical Product and Process Modeling ◽

10.1515/cppm-2021-0020 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Akshaykumar Naregalkar ◽

Subbulekshmi Durairaj

Keyword(s):

Linear System ◽

Regulatory Control ◽

Hammerstein Model ◽

Support Vector ◽

Model Structure ◽

Linear Dynamics ◽

Vector Machines ◽

Non Linear ◽

Laguerre Filters ◽

Non Linear System

Abstract A continuous stirred tank reactor (CSTR) servo and the regulatory control problem are challenging because of their highly non-linear nature, frequent changes in operating points, and frequent disturbances. System identification is one of the important steps in the CSTR model-based control design. In earlier work, a non-linear system model comprises a linear subsystem followed by static nonlinearities and represented with Laguerre filters followed by the LSSVM (least squares support vector machines). This model structure solves linear dynamics first and then associated nonlinearities. Unlike earlier works, the proposed LSSVM-L (least squares support vector machines and Laguerre filters) Hammerstein model structure solves the nonlinearities associated with the non-linear system first and then linear dynamics. Thus, the proposed Hammerstein’s model structure deals with the nonlinearities before affecting the entire system, decreasing the model complexity and providing a simple model structure. This new Hammerstein model is stable, precise, and simple to implement and provides the CSTR model with a good model fit%. Simulation studies illustrate the benefit and effectiveness of the proposed LSSVM-L Hammerstein model and its efficacy as a non-linear model predictive controller for the servo and regulatory control problem.

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