Hybrid Active and Semi-Active Control for Vibration Suppression in Flexible Structures

2016 ◽  
Author(s):  
Irfan Ullah Khan ◽  
David Wagg ◽  
Neil D. Sims
Keyword(s):  
Active Control ◽  
Vibration Suppression ◽  
Hybrid Control ◽  
Sliding Mode ◽  
Flexible Structures ◽  
Active System ◽  
Active Device ◽  
Hybrid Controller ◽  
System A ◽  
Simulation And Experiment

A new hybrid control methodology is presented for vibration suppression in flexible structures, where an active actuator is used to assist a nearby semi-active device to achieve a control performance close to that of a fully active system. The clipping phenomenon, typical of semi-active control, is reduced to a large extent by the proposed hybrid controller. The immersion and invariance methodology along with sliding mode control is used to create the hybrid controller. The result is that as the semi-active controller switches off in the hybrid controller, the active actuator injects the required energy into the system. A two degree of freedom system with cubic stiffness is used as an example system. Both simulation and experiment data are presented to demonstrate the usefulness of the proposed idea. The proposed hybrid controller shows robust results as compared to just using a semi-active controller.

Analysis of Vibration Control due to Strong Earthquakes

2010 ◽  
Vol 163-167 ◽  
pp. 4179-4184 ◽  
Author(s):  
He Len Wu
Keyword(s):  
Control System ◽  
Active Control ◽  
Base Isolation ◽  
Hybrid Control ◽  
Ground Motions ◽  
Isolation System ◽  
System A ◽  
Base Isolation System ◽  
Active Control System ◽  
Hybrid Control System

The paper proposes an aseismic hybrid control system to control the response of structures subjected to large ground motions caused by large magnitude earthquakes. The proposed hybrid control system consists of a base isolation system (laminated rubber bearings) connected to an active control system (a tuned mass damper and an actuator). The base isolation system is used to decouple the horizontal ground motions from the structure, whereas the active control system is used to protect the safety and integrity of the base isolation system. A 5-story benchmark building model is developed to study the effectiveness of the hybrid control system against different ground motions. It was found from the numerical results that rubber bearing system alone shows good performance and resists ground motion due to Hachinohe 1968, Kobe 1995, and Northridge 1994 earthquakes, but is somewhat unable to protect the model against El-Centro 1940 earthquake. After the installation of an active control system onto the rubber-isolated model, further improvements to earthquake resistance against these four earthquakes were observed, especially against the El-Centro earthquake. The merit of the hybrid control system lies in its capability to protect against different ground motions, with varying intensity and frequency content.

Two-stage sliding mode controller for vibration suppression of a flexible pointing system

2001 ◽  
Vol 215 (2) ◽  
pp. 155-166 ◽  
Author(s):  
J-H Park ◽  
K-W Kim ◽  
H-H Yoo
Keyword(s):  
Vibration Suppression ◽  
Sliding Mode ◽  
Sliding Mode Controller ◽  
Two Stage ◽  
Bending Vibrations ◽  
System A ◽  
Hydraulic Servo ◽  
Pointing Accuracy ◽  
Simulation Results ◽  
Tip Position

The performance of pointing systems mounted on top of a vehicle can be affectedby the bending vibrations as the vehicle runs on a bump course. In order to improve the pointing performance, the vibrations of the pointing structure should be suppressed. In this paper, a non-linear controller is designed to control the tip position of the pointing system while actively suppressing the vibrations. To cope with high-order dynamics and non-linearity of the plant and the hydraulic actuating system, a two-stage sliding mode controller is designed. The desired actuating pressure is obtained in the first stage and then the input current to the hydraulic servo system is computed to generate the pressure. The simulation results show the effectiveness of this scheme and the improvements obtained in pointing accuracy.

Control of a shimmy vibration in vehicle steering system using a magneto-rheological damper

2016 ◽  
Vol 24 (4) ◽  
pp. 797-807 ◽  
Author(s):  
Saikat Dutta ◽  
Seung-Bok Choi
Keyword(s):  
Dynamic Model ◽  
Degrees Of Freedom ◽  
Vibration Suppression ◽  
Sliding Mode ◽  
Steering System ◽  
Sliding Mode Controller ◽  
Control Logic ◽  
Adaptive Sliding Mode Controller ◽  
System A ◽  
Magneto Rheological

Vehicle stability largely depends on the vibration of the steering system. A four degrees of freedom dynamic model of an automotive steering system with a magneto-rheological damper is presented in this study. Firstly, an equivalent mathematical model of the steering system is developed. The nonlinear equation of motion obtained from the dynamic model is then linearized around its equilibrium point to make it suitable for the design of an appropriate controller for vibration suppression. In this work, a new type of adaptive sliding mode controller is designed for control of the magneto-rheological damper and hence to control unwanted vibration. It is shown that the proposed control logic is very effective for settling steering motion near the equilibrium position. The shimmy vibrations of the wheels are reduced by a considerable amount and the steering system becomes stable. In addition, a comparative work is undertaken between the proposed controller and an ordinary sliding mode controller to demonstrate the advantage of the proposed methodology.

Hybrid Robust Control for Gantry Crane System

2010 ◽  
Vol 29-32 ◽  
pp. 2082-2088 ◽  
Author(s):  
Zhi Mei Chen ◽  
Wen Jun Meng ◽  
Ming Hui Zhao ◽  
Jing Gang Zhang
Keyword(s):  
Sliding Mode Control ◽  
Hybrid Control ◽  
Sliding Mode ◽  
Gantry Crane ◽  
Input Shaping ◽  
Transient Vibration ◽  
Shaping Technique ◽  
Mode Control ◽  
System A ◽  
Accurate Position

A new hybrid control scheme combining input shaping technique with robust sliding mode control is proposed for a gantry crane system. A cascade sliding-mode controller is designed to control the trolley position and eliminate the sway of load. The transient vibration is reduced further for safety problems by the input shaping technique which utilizes zero-vibration-derivative (ZVD) robust input shapers. This method can not only realize the accurate position of the trolley and eliminate the sway of the load and residual vibration, but also completely eliminate the chattering of conventional sliding mode control and improve the robustness of system. The simulation results proved its effectiveness.

Experiments in Robust Active Vibration Control Design for Slewing Flexible Structures

1999 ◽  
Author(s):  
D. G. Wilson ◽  
G. P. Starr ◽  
G. G. Parker ◽  
R. D. Robinett
Keyword(s):  
Control System ◽  
Vibration Suppression ◽  
Sliding Mode ◽  
Flexible Structures ◽  
Large Angle ◽  
Sensor Data ◽  
Flexible Structure ◽  
Control Effort ◽  
Active Vibration ◽  
Tip Mass

Abstract In this paper we present a hybrid Sliding Mode Control (SMC) and Constant Amplitude Feedback Control (CAFC) architecture for slewing flexible structures. The SMC controller is used to servo the flexible structure and the CAFC is used to suppress residual vibrations of the flexible structure. A single-axis encoder/DC motor/harmonic drive assembly is used for large angle slewing. A graphite/epoxy composite structure with embedded strain sensors/actuators is used for active vibration suppression. The results of this study include the analytical dynamic and control system development with experimental verification. The hybrid control algorithm uses the output sensor data from the encoder and strain sensor along with filters to derive velocity information to compute the control effort for the motor and strain actuators. Near-minimum time maneuvers based on an equivalent rigid structure are used to slew the flexible active structure. The tip mass was varied to evaluate control system robustness. Experimental slewing studies were performed to compare the benefits of using active rather than passive structures. For the active case the experimental results showed a reduction in residual vibration and settling time.

scholarly journals Robust Adaptive Control for an Aircraft Landing Gear Equipped with a Magnetorheological Damper

2020 ◽  
Vol 10 (4) ◽  
pp. 1459 ◽  
Author(s):  
Quoc Viet Luong ◽  
Dae-Sung Jang ◽  
Jai-Hyuk Hwang
Keyword(s):  
Hybrid Control ◽  
Sliding Mode ◽  
Landing Gear ◽  
Robust Adaptive Control ◽  
Magnetorheological Damper ◽  
Parametric Uncertainties ◽  
Active System ◽  
Damping Force ◽  
Passive Damper ◽  
Robust Adaptive

A landing gear of an aircraft is required to function at touchdown in different landing scenarios with parametric uncertainties. A typical passive damper in a landing gear has limited performance in differing landing scenarios, which can be overcome with magnetorheological (MR) dampers. An MR damper is a semi-active system that can adjust damping force by changing the amount of electric current applied to it. This paper proposes a new robust controller based on model reference sliding mode control and adaptive hybrid control to improve the efficiency of absorbing landing impact energy, not only considering the variables of aircraft weight and sink speed but also managing uncertainties, such as ambient temperature and passive damping coefficient. To verify the effectiveness of the proposed controller, comparative numerical simulations were performed with a passive damper, a skyhook controller, and the proposed controller under various landing scenarios. The simulation results show that the proposed controller improves the total energy absorber efficiency by up to 10% higher than that of the skyhook controller. In addition, the proposed controller is demonstrated to have better adaptability and robustness than the other control algorithms in the differing landing scenarios and parametric uncertainties.

scholarly journals Independent Modal Variable Structure Fuzzy Active Vibration Control of Cylindrical Thin Shells Laminated with Photostrictive Actuators

2013 ◽  
Vol 20 (4) ◽  
pp. 693-709 ◽  
Author(s):  
R.B. He ◽  
S.J. Zheng ◽  
H.T. Wang
Keyword(s):  
Vibration Control ◽  
Vibration Suppression ◽  
Sliding Mode ◽  
Active Vibration Control ◽  
Flexible Structures ◽  
Variable Structure ◽  
Structure Control ◽  
Coupling Equations ◽  
Active Vibration ◽  
Control Forces

Photostrictive actuator, which can produce photodeformation strains under the activation of ultraviolet lights, is a new promising non-contact photoactuation technique for active vibration control of flexible structures. Generally, the membrane control action plays a major role in vibration control of flexible thin shell structures. However, it is unfortunate that the existing photostrictive actuator configuration can not induce negative membrane control forces. In this paper, a novel multi-layer actuator configuration is first presented to remedy this deficiency, followed by presenting the photostrictive/shell coupling equations of thin cylindrical shells laminated with the proposed multi-layer actuator configuration. Moreover, considering the time-variant and nonlinear dynamic characteristics of photostrictive actuator, variable structure self-adjusting parameter fuzzy active controller is explored to overcome disadvantages of conventional control schemes, in which off-line fuzzy control table is adopted. The optimal switching surface is derived to increase the range of sliding mode to facilitate vibration suppression. A continuous function is used to replace the sign function for reducing the variable structure control chattering. Finally, two case studies are carried out to evaluate the effectiveness of the proposed actuator configuration and the control scheme. Numerical simulation results demonstrate that the proposed actuator configuration is effective in shell actuation and control. It is also suggested that the proposed control strategy could give better control responses than the proportional velocity feedback.

Distributed Hybrid Vibration Absorbers for Shock and Forced Vibrations

2012 ◽  
Vol 166-169 ◽  
pp. 1709-1712
Author(s):  
Lei Chen
Keyword(s):  
Steady State ◽  
Forced Vibration ◽  
Vibration Suppression ◽  
Hybrid Control ◽  
Control Strategies ◽  
Flexible Structures ◽  
Experimental Studies ◽  
Integrated System ◽  
Transient Vibration ◽  
Hybrid Control System

The control methods used for free/shock vibration suppression are normally different from those used for forced vibration cancellation, because shock vibration is regarded as a type of transient vibration that is different in nature from steady-state forced vibration. However, both steady-state and shock excitations may occur in flexible structures, so there is a need to control both types of vibrations. To show the integration of the two different vibration control strategies, a hybrid control system based on adhesive strain gauges and PZT patches is proposed to construct a distributed resonant absorber and shock absorber together. The hybrid system is governed by a control arbitrator that decides which absorber should be active according to the different excitation conditions. The effectiveness of the integrated system is shown through simulation and experimental studies.

Sign in / Sign up

Export Citation Format

Share Document