Adaptive Vibration Control of an Axially Moving String

1999 ◽  
Vol 121 (1) ◽  
pp. 41-49 ◽  
Author(s):  
M. S. de Queiroz ◽  
D. M. Dawson ◽  
C. D. Rahn ◽  
F. Zhang
Keyword(s):  
Control Strategies ◽  
Adaptive Controller ◽  
String Tension ◽  
Control Force ◽  
Control Laws ◽  
Axially Moving String ◽  
Model Based ◽  
Parameter Field ◽  
Axially Moving ◽  
Mechanical Guide

In this paper, the displacement of an axially moving string is regulated using a control force and a control torque applied to the string via a mechanical guide. Given the hybrid model of the string system (i.e., distributed parameter field equation coupled to discrete actuator equations), Lyapunov-type arguments are utilized to design model-based and adaptive control laws that exponentially and asymptotically stabilize the string displacement, respectively. The proposed control laws are based on measurements of the string displacement, velocity, slope, and slope rate at the mechanical guide. While the model-based controller requires exact knowledge of the actuator/string parameters (e.g., actuator mass and string tension), the adaptive controller estimates the parameters online. Dynamic simulation results demonstrate the vibration damping provided by the control strategies.

Vibration Control of a Distributed Axially Moving String Using Two Actuators

1997 ◽  
Author(s):  
M. S. de Queiroz ◽  
D. M. Dawson ◽  
C. D. Rahn ◽  
F. Zhang
Keyword(s):  
Control Strategy ◽  
Distributed Parameter ◽  
Control Force ◽  
Control Torque ◽  
Type Analysis ◽  
Control Laws ◽  
Parameter Field ◽  
Simulation Results ◽  
Axially Moving ◽  
Mechanical Guide

Abstract In this paper, we consider the problem of regulating the displacement of an axial moving string using a control force and a control torque applied to the string via a mechanical guide. Given the hybrid model of the web system (i.e., distributed parameter field equation coupled to a discrete actuator equation), a Lyapunov-type analysis is utilized to design exact model knowledge and adaptive control laws that exponentially and asymptotically stabilize the string displacement, respectively. Dynamic simulation results demonstrate the vibration damping provided by the control strategy.

Stabilization of an Axially Moving String by Nonlinear Boundary Feedback

1999 ◽  
Vol 121 (1) ◽  
pp. 117-121 ◽  
Author(s):  
Rong-Fong Fung ◽  
Jinn-Wen Wu ◽  
Sheng-Luong Wu
Keyword(s):  
Nonlinear Boundary ◽  
Mechanical Energy ◽  
Control Laws ◽  
Axially Moving String ◽  
Boundary Feedback ◽  
Boundary Velocity ◽  
Total Mechanical Energy ◽  
Axially Moving ◽  
The Right ◽  
Nonlinear Boundary Feedback

In this paper, we consider the system modeled by an axially moving string and a mass-damper-spring (MDS) controller, applied at the right-hand side (RHS) boundary of the string. We are concerned with the nonlinear string and the effect of the control mechanism. We stabilize the system through a proposed boundary velocity feedback control law. Linear and nonlinear control laws through this controller are proposed. In this paper, we find that a linear boundary feedback caused the total mechanical energy of the system to decay an asymptotically, but it fails for an exponential decay. However, a nonlinear boundary feedback controller can stabilize the system exponentially. The asymptotic and exponential stability are verified.

Active Vibration Control of the Axially Moving String Using Space Feedforward and Feedback Controllers

1996 ◽  
Vol 118 (3) ◽  
pp. 306-312 ◽  
Author(s):  
S. Ying ◽  
C. A. Tan
Keyword(s):  
Vibration Control ◽  
Feedforward Control ◽  
Active Vibration Control ◽  
Upstream Region ◽  
Control Force ◽  
Feedback Controllers ◽  
Axially Moving String ◽  
Downstream Region ◽  
Active Vibration ◽  
Axially Moving

Active vibration control of an axially moving string using space feedforward and feedback controllers is presented. Closed-form results for the transverse response of both the uncontrolled and controlled string are given in the s domain. The space feedforward controller is established by employing the idea of wave cancellation. The proposed control law indicates that vibration in the region downstream of the control force can be cancelled. With the space feedforward control, the mode shapes of the axially moving string are changed such that the free response tends to zero in the downstream region. An interesting physical interpretation is that the control force acts effectively as a holder (active support) which limits the vibration of the string to the upstream region and eliminates any vibration in the downstream region. Simulation results show that the response of the string to both sinusoidal and random excitations is suppressed by applying the space feedforward control. The feedback controller is introduced to attenuate the response of the string due to undesired disturbances in the downstream.

Adaptive Boundary Control of an Axially Moving String System

2002 ◽  
Vol 124 (3) ◽  
pp. 435-440 ◽  
Author(s):  
Rong-Fong Fung ◽  
Jinn-Wen Wu ◽  
Pai-Yat Lu
Keyword(s):  
Boundary Control ◽  
Tracking Error ◽  
Torque Control ◽  
Control Force ◽  
Unknown Parameters ◽  
System Equation ◽  
Axially Moving String ◽  
Coupling System ◽  
Axially Moving ◽  
Adaptive Boundary Control

This paper proposes an adaptive boundary control to an axially moving string system, which couples with a mass-damper-spring (MDS) controller at its right-hand-side (RHS) boundary. Unknown parameters appearing in the system equation are assumed constant and estimated on-line by using adaptation laws. The adaptive computed-torque control algorithm applied to robot manipulators of lumped systems is extended to design the adaptive boundary controller for the coupling system. It is found that the control force and update laws depend only on the displacement, velocity and slope of the string at the RHS boundary. Lyapunov stability guarantees the convergence of the tracking error to zero. Finally, the performance of the proposed controller is demonstrated by numerical simulations.

scholarly journals Model-based methodology for the design of optimal control strategies in MBR plants

2017 ◽  
Vol 75 (11) ◽  
pp. 2546-2553 ◽  
Author(s):  
Juan Odriozola ◽  
Sergio Beltrán ◽  
Montse Dalmau ◽  
Luis Sancho ◽  
Joaquim Comas ◽  
...  
Keyword(s):  
Optimal Control ◽  
Total Nitrogen ◽  
Conceptual Knowledge ◽  
Wastewater Treatment Plants ◽  
Control Strategies ◽  
Control Laws ◽  
Operational Strategies ◽  
Model Based ◽  
Different Temperatures ◽  
Input Variables

This paper proposes a model-based methodology that allows synthesising the most appropriate strategies for optimising the operation of wastewater treatment plants (WWTPs). The methodology is applied with the aim of maximising the nitrogen removal in membrane bioreactors (MBRs). The proposed procedure is based on a systematic approach composed of four steps. First, a sensitivity analysis of the input variables is carried out in order to obtain a first assessment of the potential for operational improvements. Then, the optimum input variable values are calculated by a model-based optimisation algorithm that minimises a cost function associated with the effluent total nitrogen at different temperatures. Then, the optimum operational strategies are identified. Finally, these operational strategies form the conceptual knowledge base for designing automatic control laws. The obtained optimal control strategies have shown a significant improvement in performance in comparison with fixed operation for the studied case, reducing the total nitrogen by 40%.

Model-based control of the substrate concentration in an aeration basin using the wastewater level

1998 ◽  
Vol 37 (12) ◽  
pp. 335-342 ◽  
Author(s):  
Jacek Czeczot
Keyword(s):  
Substrate Concentration ◽  
Consumption Rate ◽  
Least Square Method ◽  
Estimation Procedure ◽  
Adaptive Controller ◽  
Open Loop ◽  
Least Square ◽  
Substrate Consumption ◽  
Model Based ◽  
Effluent Flow Rate

This paper deals with the minimal-cost control of the modified activated sludge process with varying level of wastewater in the aerator tank. The model-based adaptive controller of the effluent substrate concentration, basing on the substrate consumption rate and manipulating the effluent flow rate outcoming from the aerator tank, is proposed and its performance is compared with conventional PI controller and open loop behavior. Since the substrate consumption rate is not measurable on-line, the estimation procedure on the basis of the least-square method is suggested. Finally, it is proved that cooperation of the DO concentration controller with the adaptive controller of the effluent substrate concentration allows the process to be operated at minimum costs (low consumption of aeration energy).

Characteristic model-based adaptive control for cryogenic wind tunnels

2020 ◽  
pp. 014233122096065
Author(s):  
Chenhui Yu ◽  
Fei Liao ◽  
Haibo Ji ◽  
Wenhua Wu
Keyword(s):  
Reynolds Number ◽  
Wind Tunnel ◽  
Flow Field ◽  
Control Problem ◽  
Mimo System ◽  
Adaptive Controller ◽  
Characteristic Model ◽  
Model Based ◽  
Field Control ◽  
Cryogenic Wind Tunnel

With the increasing requirement of Reynolds number simulation in wind tunnel tests, the cryogenic wind tunnel is considered as a feasible method to realize high Reynolds number. Characteristic model-based adaptive controller design method is introduced to flow field control problem of the cryogenic wind tunnel. A class of nonlinear multi-input multi-output (MIMO) system is given for theoretical research that is related to flow field control of the cryogenic wind tunnel. The characteristic model in the form of second-order time-varying difference equations is provided to represent the system. A characteristic model-based adaptive controller is also designed correspondingly. The stability analysis of the closed loop system composed of the characteristic model or the exact discrete-time model and the proposed controller is investigated respectively. Numerical simulation is presented to illustrate the effectiveness of this control method. The modeling and control problem based on characteristic model method for a class of MIMO system are studied and first applied to the cryogenic wind tunnel control field.

scholarly journals The Role of Trip Lengths Calibration in Model-Based Perimeter Control Strategies

2021 ◽  
pp. 1-11
Author(s):  
Sergio F. A. Batista ◽  
Deepak Ingole ◽  
Ludovic Leclercq ◽  
Monica Menendez
Keyword(s):  
Control Strategies ◽  
Model Based

Control Strategies for Semi-Active Lorry Suspensions

1996 ◽  
Vol 210 (2) ◽  
pp. 161-178 ◽  
Author(s):  
D Cebon ◽  
F H Besinger ◽  
D J Cole
Keyword(s):  
Linear Models ◽  
Control Strategies ◽  
Power Input ◽  
Optimum Level ◽  
Passive Damping ◽  
Control Laws ◽  
Body Acceleration ◽  
Performance Improvements ◽  
Full State Feedback ◽  
Active Damper

The optimum level of passive damping for minimizing the root mean square (r.m.s.) dynamic tyre force and r.m.s. body acceleration of a heavy vehicle is determined by testing a damper in a ‘hardware-in-the-loop’ (HiL) test rig. Two different control strategies [‘modified skyhook damping’ (MSD), and linear optimal control with full state feedback (FSF)] are investigated theoretically using linear models, and suspension force control laws are derived. These control laws, along with simple ‘on–off’ control, are then tested experimentally using a prototype semi-active damper which is controlled so as to follow the demanded force, except when power input is required. The achievable performance improvements are compared and differences between the linear theory, computer simulations and experimental performance are discussed. It is found that using FSF control, r.m.s. body acceleration and r.m.s. tyre force can be reduced simultaneously by 28 and 21 per cent of their values for optimal passive damping.

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