scholarly journals Sound Field Control in Surround Screen Speaker Array by WFS and CBT Algorithms

2022 ◽  
Vol 2148 (1) ◽  
pp. 012001
Author(s):  
Rui Huan ◽  
Xi Zhao
Keyword(s):  
Field Distribution ◽  
Control Algorithm ◽  
Sound Field ◽  
Control Algorithms ◽  
Sound Reproduction ◽  
Reproduction System ◽  
Field Control

Abstract This paper proposes a method to solve the problem that the sound reproduction system cannot work when the movie screen is made by a sound-proof material such as LED. It is demonstrated in an array of 192 speakers to surround a screen for sound reproduction, called surround screen speaker array. The speaker array is built in an actual cinema. The sound field control algorithms are implemented by mixers. In order to improve the uneven sound field distribution and sound field aliasing caused by the speaker array, two algorithms WFS and CBT are used in this paper. A new control algorithm is proposed and demonstrated to improve the uniformity of the sound field distribution and reduce the sound field interference.

scholarly journals Vibration Control of Buildings Using Magnetorheological Damper: A New Control Algorithm

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Aly Mousaad Aly
Keyword(s):  
Vibration Control ◽  
Control Algorithm ◽  
Fuzzy Logic Controller ◽  
Mr Damper ◽  
Maximum Energy ◽  
Magnetorheological Damper ◽  
Control Algorithms ◽  
Earthquake Loads ◽  
Building Model ◽  
Lyapunov Controller

This paper presents vibration control of a building model under earthquake loads. A magnetorheological (MR) damper is placed in the building between the first floor and ground for seismic response reduction. A new control algorithm to command the MR damper is proposed. The approach is inspired by a quasi-bang-bang controller; however, the proposed technique gives weights to control commands in a fashion that is similar to a fuzzy logic controller. Several control algorithms including decentralized bang-bang controller, Lyapunov controller, modulated homogeneous friction controller, maximum energy dissipation controller, and clipped-optimal controller are used for comparison. The new controller achieved the best reduction in maximum interstory drifts and maximum absolute accelerations over all the control algorithms presented. This reveals that the proposed controller with the MR damper is promising and may provide the best protection to the building and its contents.

The Use of Damping Based Semi-Active Control Algorithms in the Mechanical Smart-Spring System

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Wander Gustavo Rocha Vieira ◽  
Fred Nitzsche ◽  
Carlos De Marqui
Keyword(s):  
Active Control ◽  
Control Algorithm ◽  
Control Strategies ◽  
Vibration Reduction ◽  
Flow Analysis ◽  
Coupled Systems ◽  
Control Technique ◽  
Control Algorithms ◽  
Control Techniques ◽  
Spring Mechanism

In recent decades, semi-active control strategies have been investigated for vibration reduction. In general, these techniques provide enhanced control performance when compared to traditional passive techniques and lower energy consumption if compared to active control techniques. In semi-active concepts, vibration attenuation is achieved by modulating inertial, stiffness, or damping properties of a dynamic system. The smart spring is a mechanical device originally employed for the effective modulation of its stiffness through the use of semi-active control strategies. This device has been successfully tested to damp aeroelastic oscillations of fixed and rotary wings. In this paper, the modeling of the smart spring mechanism is presented and two semi-active control algorithms are employed to promote vibration reduction through enhanced damping effects. The first control technique is the smart-spring resetting (SSR), which resembles resetting control techniques developed for vibration reduction of civil structures as well as the piezoelectric synchronized switch damping on short (SSDS) technique. The second control algorithm is referred to as the smart-spring inversion (SSI), which presents some similarities with the synchronized switch damping (SSD) on inductor technique previously presented in the literature of electromechanically coupled systems. The effects of the SSR and SSI control algorithms on the free and forced responses of the smart-spring are investigated in time and frequency domains. An energy flow analysis is also presented in order to explain the enhanced damping behavior when the SSI control algorithm is employed.

Differences in speech intelligibility in noise between native and non-native listeners under ambisonics-based sound reproduction system

2021 ◽  
Vol 184 ◽  
pp. 108368
Author(s):  
C. T. Justine Hui ◽  
Eugena Au ◽  
Shirley Xiao ◽  
Yusuke Hioka ◽  
Hinako Masuda ◽  
...  
Keyword(s):  
Speech Intelligibility ◽  
Sound Reproduction ◽  
Reproduction System

Frequency Shaped Semi-Active Control for Magnetorheological Fluid-Based Vibration Control Systems

2013 ◽  
Author(s):  
Young-Tai Choi ◽  
Norman M. Wereley ◽  
Gregory J. Hiemenz
Keyword(s):  
Vibration Control ◽  
Control Systems ◽  
Active Control ◽  
Control Algorithm ◽  
Active Vibration Control ◽  
Control Algorithms ◽  
Model Parameters ◽  
Mr Fluid ◽  
Control Current ◽  
Active Vibration

Novel semi-active vibration controllers are developed in this study for magnetorheological (MR) fluid-based vibration control systems, including: (1) a band-pass frequency shaped semi-active control algorithm, (2) a narrow-band frequency shaped semi-active control algorithm. These semi-active vibration control algorithms designed without resorting to the implementation of an active vibration control algorithms upon which is superposed the energy dissipation constraint. These new Frequency Shaped Semi-active Control (FSSC) algorithms require neither an accurate damper (or actuator) model, nor system identification of damper model parameters for determining control current input. In the design procedure for the FSSC algorithms, the semi-active MR damper is not treated as an active force producing actuator, but rather is treated in the design process as a semi-active dissipative device. The control signal from the FSSC algorithms is a control current, and not a control force as is typically done for active controllers. In this study, two FSSC algorithms are formulated and performance of each is assessed via simulation. Performance of the FSSC vibration controllers is evaluated using a single-degree-of-freedom (DOF) MR fluid-based engine mount system. To better understand the control characteristics and advantages of the two FSSC algorithms, the vibration mitigation performance of a semi-active skyhook control algorithm, which is the classical semi-active controller used in base excitation problems, is compared to the two FSSC algorithms.

Interface for barge-in free spoken dialogue system using adaptive sound field control

2004 ◽  
Author(s):  
Tatsunori Asai ◽  
Shigeki Miyabe ◽  
Hiroshi Saruwatari ◽  
Kiyohiro Shikano
Keyword(s):  
Sound Field ◽  
Dialogue System ◽  
Spoken Dialogue ◽  
Spoken Dialogue System ◽  
Field Control

Normalized Adaptive Hybrid Control Algorithms for Helicopter Vibration with Variable Rotor Speed

2021 ◽  
Author(s):  
Kai Lang ◽  
Pinqi Xia ◽  
Edward C. Smith ◽  
Lina Shang
Keyword(s):  
Control Algorithm ◽  
Hybrid Control ◽  
Active Vibration Control ◽  
Frame Structure ◽  
Control Algorithms ◽  
Flight Performance ◽  
Rotor Speed ◽  
Frequency Tracking ◽  
Harmonic Control ◽  
Active Vibration

Variable rotor speed technology implemented in a helicopter can improve the flight performance, reduce the required power, and increase the flight speed. However, variable rotor speed changes the frequencies of rotor vibratory loads and may produce helicopter fuselage resonance under the excitation of the rotor vibratory loads. Active vibration control (AVC) has been effectively used in vibration reduction of helicopter fuselages. However, the frequency domain control algorithms that are currently used have poor adaptability in controlling vibration with variable frequencies (i.e., during time varying rotor speeds). In order to effectively improve control convergence, adaptability, and effectiveness, the normalized adaptive hybrid control algorithms containing both the normalized adaptive harmonic control algorithm and the normalized frequency tracking algorithm have been presented in this paper. Simulations of AVC with variable frequencies on a dynamically similar frame structure of a helicopter fuselage driven by piezoelectric stack actuators installed on the gearbox support struts show that the normalized adaptive hybrid control algorithms can accurately track the changes in rotor load frequencies and can be effectively used in the AVC of a helicopter with variable rotor speed.

scholarly journals Smooth Tracking Trajectory Generation of Large Antenna

2016 ◽  
Vol 53 (1) ◽  
pp. 24-33 ◽  
Author(s):  
S. Upnere ◽  
N. Jekabsons ◽  
U. Locans
Keyword(s):  
Pid Control ◽  
Control Algorithm ◽  
Case Analysis ◽  
Control Algorithms ◽  
Control Methods ◽  
Antenna Feed ◽  
Feed Forward Control ◽  
Order Polynomial ◽  
Smooth Tracking ◽  
Tracking Trajectory

Abstract The current paper presents an engineering approach for studies of the control algorithm designed for a mechanically robust large antenna. Feed-forward control methods with the 3rd-order polynomial tracking algorithm are supplemented to the original feed-back PID control system. Dynamical model of the existing servo system of 32m radio telescope has been developed to widen a case analysis of observation sessions and efficiency of the control algorithms due to limited access to an antenna. Algorithms along with the results from the system implemented on a real antenna as well as model results are presented.

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