Energy Dissipation Behavior of an Autonomous Controller for Semi-Active Control Device

2009 ◽  
Author(s):  
Ming-Hsiang Shih ◽  
Wen-Pei Sung
Keyword(s):  
Control System ◽  
Energy Dissipation ◽  
Active Control ◽  
High Reliability ◽  
Structural Response ◽  
Control Device ◽  
Manufacturing Cost ◽  
Moving Direction ◽  
Control Order ◽  
The Right

In this research, autonomous controller is developed to provide the function of “Sensing-Computing-Transferring” for improving of energy dissipation capability of semi-active control device. This proposed controller has qualifications of detecting structural response under the excitation of earthquake; it depends on the control law to produce control order to adjust and control the action of semi-active control damper. The principle of this controller is: 1.) autonomous controller and damper-added stiffness element are parallel connection; 2.) the direction of pressure force and velocity moving direction of structure are changed simultaneously by this controller; 3.) the action of switching direction of damper has been finished when the tiny displacement of structure is happened by reverse process of moving direction of structure. Practically, this controller was simulated by connecting soft springs, damper and actuator in serial. The experimental results indicate that the function and energy-dissipating behavior of this proposed controller is similar to traditional semi-active controller except that this controller can switch the damper status at the right moment. This proposed controller can replace the detector, central control computer and damping controller included in original semi-active control system. The advantages of this developed autonomous controller are: 1.) low manufacturing cost; 2.) low requirement of system maintenance; 3) high reliability of control system.

Scheduling Strategy of Multiple Semi-Active Controllers With Information on the Disturbance and the Structural Response

2016 ◽  
Author(s):  
Kazuhiko Hiramoto ◽  
Taichi Matsuoka ◽  
Katsuaki Sunakoda
Keyword(s):  
Optimal Control ◽  
Control System ◽  
Active Control ◽  
Structural Response ◽  
Design Parameters ◽  
Control Law ◽  
Control Performance ◽  
Multiple Control ◽  
Control Laws ◽  
Scheduling Strategy

A scheduling strategy of multiple semi-active control laws for various earthquake disturbances is proposed to maximize the control performance. Generally, the semi-active controller for a given structural system is designed as a single control law and the single control law is used for all the forthcoming earthquake disturbances. It means that the general semi-active control should be designed to achieve a certain degree of the control performance for all the assumed disturbances with various time and/or frequency characteristics. Such requirement on the performance robustness becomes a constraint to obtain the optimal control performance. We propose a scheduling strategy of multiple semi-active control laws. Each semi-active control law is designed to achieve the optimal performance for a single earthquake disturbance. Such optimal control laws are scheduled with the available data in the control system. As the scheduling mechanism of the multiple control laws, a command signal generator (CSG) is defined in the control system. An artificial neural network (ANN) is adopted as the CSG. The ANN-based CSG works as an interpolator of the multiple control laws. Design parameters in the CSG are optimized with the genetic algorithm (GA). Simulation study shows the effectiveness of the approach.

Effect of Response Related Weighting Matrices on Performance of Active Control Systems for Nonlinear Frames

2017 ◽  
Vol 17 (03) ◽  
pp. 1750030
Author(s):  
Mohtasham Mohebbi ◽  
Abdolreza Joghataie ◽  
Hamed Rasouli Dabbagh
Keyword(s):  
Control System ◽  
Control Systems ◽  
Active Control ◽  
Structural Response ◽  
Control Law ◽  
Control Force ◽  
Online Measurements ◽  
Active Control System ◽  
Distributed Genetic Algorithm ◽  
Response Feedback

In this paper, the effect of various arrangements of displacement, velocity and acceleration related weighting matrices on the performance of active control systems on nonlinear frames has been studied. Different arrangements of weighting matrices and feedback combinations of the response have been considered to design the active controllers using a single actuator for reducing the response of an eight-storey bilinear hysteretic frame under white noise excitations. The nonlinear Newmark-based instantaneous optimal control algorithm has been used, where the distributed genetic algorithm (DGA) is employed to determine the proper set of weighting matrices. For each set of feedback and weighting matrices, the active control system has been designed with the optimal weights determined. Here, the objective is to minimize the maximum control force required to reduce the maximum structural drift to a value below the desired level. The numerical results of simulation show that, for the cases studied, the use of different arrangements of weighting matrices in the proposed method for the performance index of the active control law has no significant impact on the performance of the active control system. However, the type of response feedback combination included in the control law considerably affects the performance, and the controllers designed based on velocity feedback have been found to be more effective. It was also shown that for all the weight-cases, using the full feedback of response can lead to design controllers that require minimum control force to reduce the structural response with more online measurements. The robustness of the designed controllers for different weighting matrices arrangements and feedback combinations has also been tested under a number of real earthquake excitations with the results discussed.

Research on Automatic Control System of Suspended Access Platform Based on PIC16F877A

2010 ◽  
Vol 43 ◽  
pp. 147-150
Author(s):  
Xue Chen Jiang ◽  
Jia Sun ◽  
Ke Zhang ◽  
Hua Guo ◽  
Yu Hou Wu
Keyword(s):  
Control System ◽  
Data Processing ◽  
Automatic Control ◽  
Automatic Control System ◽  
High Reliability ◽  
Control Device ◽  
Time Data ◽  
Angle Sensor ◽  
Overload Protection ◽  
Real Time Data

The design of automatic control system mounted on the suspended access platform is put forward. With advantages of the microcontroller in real time data acquisition and data processing, PIC16F877A is applied as controller of the system. Angle sensor and pull sensor are applied as measuring elements of the system. The control system can implement functions of automatic leveling and overload protection. The new automatic control device is tested to be easy to operate and high reliability. It completely meets requirements and suits for multi-series specifications suspended access platforms, worth to be widely extended in applications.

Active control of compressor noise in the machinery room of refrigerators

2019 ◽  
Vol 67 (5) ◽  
pp. 350-362
Author(s):  
J. M. Ku ◽  
W. B. Jeong ◽  
C. Hong
Keyword(s):  
Control System ◽  
Active Control ◽  
Weighting Function ◽  
Reference Signal ◽  
Active Noise Control ◽  
Dominant Frequency ◽  
Time Signal ◽  
Frequency Noise ◽  
Sound Power ◽  
Fxlms Algorithm

The low-frequency noise generated by the vibration of the compressor in the machinery room of refrigerators is considered as annoying sound. Active noise control is used to reduce this noise without any change in the design of the compressor in the machinery room. In configuring the control system, various signals are measured and analyzed to select the reference signal that best represents the compressor noise. As the space inside the machinery room is small, the size of a speaker is limited, and the magnitude of the controller transfer function is designed to be small at low frequencies, the controller uses FIR filter structure converged by the FxLMS algorithm using the pre-measured time signal. To manage the convergence speed for each frequency, the frequency-weighting function is applied to FxLMS algorithm. A series of measurements are performed to design the controller and to evaluate the control performance. After the control, the sound power transmitted by the refrigerator is reduced by 9 dB at the first dominant frequency (408 Hz in this case) and 3 dB at the second dominant frequency (459 Hz here), and the overall sound power decreases by 2.6 dB. Through this study, an active control system for the noise generated by refrigerator compressors is established.

Active control of the scattered radiation with a reflecting surface

2019 ◽  
Vol 67 (3) ◽  
pp. 190-196
Author(s):  
Ning Han
Keyword(s):  
Control System ◽  
Active Control ◽  
Scattered Radiation ◽  
Sound Pressure ◽  
Sound Field ◽  
Control Area ◽  
Mirror Image ◽  
Three Dimension ◽  
Control Effect ◽  
Reflecting Surface

Based on a prediction method of the scattered sound pressure, an active control system was proposed in previous work for the three-dimension scattered radiation, where all the relevant simulations and experiments were implemented in three-dimensional free sound field. However, for practical applications, such as the anti-eavesdropping system or the stealth system for submarines, the sound field conditions are usually complex, and the most common case is the one with reflecting surface. It is questionable whether the previous control system is still effective in non-free sound field, or what improvements should be operated to ensure the control effect. In this article, based on the mirror image principle, two methods of calculating the control source strengths are proposed for the scattered radiation control, and numerical simulations with one-channel and multi-channel system are implemented to detect the corresponding control effect. It is seen that the local active control for the scattered radiation is still effective, and the reduction of the sound pressure level as well as the control area is extended with the increasement of the error sensors and control sources.

scholarly journals Research on an Improved Sliding Mode Sensorless Six-Phase PMSM Control Strategy Based on ESO

Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1292
Author(s):  
Hanying Gao ◽  
Guoqiang Zhang ◽  
Wenxue Wang ◽  
Xuechen Liu
Keyword(s):  
Control System ◽  
Control Strategy ◽  
Sliding Mode ◽  
High Reliability ◽  
Permanent Magnet Synchronous Motor ◽  
Torque Ripple ◽  
Estimation Accuracy ◽  
Switching Function ◽  
Motor Speed ◽  
Rotor Position

The six-phase motor control system has low torque ripple, low harmonic content, and high reliability; therefore, it is suitable for electric vehicles, aerospace, and other applications requiring high power output and reliability. This study presents a superior sensorless control system for a six-phase permanent magnet synchronous motor (PMSM). The mathematical model of a PMSM in a stationary coordinate system is presented. The information of motor speed and position is obtained by using a sliding mode observer (SMO). As torque ripple and harmonic components affect the back electromotive force (BEMF) estimated value through the traditional SMO, the function of the frequency-variable tracker of the stator current (FVTSC) is used instead of the traditional switching function. By improving the SMO method, the BEMF is estimated independently, and its precision is maintained under startup or variable-speed states. In order to improve the estimation accuracy and resistance ability of the observer, the rotor position error was taken as the disturbance term, and the third-order extended state observer (ESO) was constructed to estimate the rotational speed and rotor position through the motor mechanical motion equation. Finally, the effectiveness of the method is verified by simulation and experiment results. The proposed control strategy can effectively improve the dynamic and static performance of PMSM.

scholarly journals Intelligent Control Wheelchair Using a New Visual Joystick

2018 ◽  
Vol 2018 ◽  
pp. 1-20 ◽  
Author(s):  
Yassine Rabhi ◽  
Makrem Mrabet ◽  
Farhat Fnaiech
Keyword(s):  
Control System ◽  
Intelligent Control ◽  
Visual Recognition ◽  
Low Cost ◽  
Control Device ◽  
Control Technique ◽  
Hand Gesture ◽  
Functional Rehabilitation ◽  
Number Of Patients ◽  
Real Patients

A new control system of a hand gesture-controlled wheelchair (EWC) is proposed. This smart control device is suitable for a large number of patients who cannot manipulate a standard joystick wheelchair. The movement control system uses a camera fixed on the wheelchair. The patient’s hand movements are recognized using a visual recognition algorithm and artificial intelligence software; the derived corresponding signals are thus used to control the EWC in real time. One of the main features of this control technique is that it allows the patient to drive the wheelchair with a variable speed similar to that of a standard joystick. The designed device “hand gesture-controlled wheelchair” is performed at low cost and has been tested on real patients and exhibits good results. Before testing the proposed control device, we have created a three-dimensional environment simulator to test its performances with extreme security. These tests were performed on real patients with diverse hand pathologies in Mohamed Kassab National Institute of Orthopedics, Physical and Functional Rehabilitation Hospital of Tunis, and the validity of this intelligent control system had been proved.

Structural Control Considering Time Delay Effect

1985 ◽  
Vol 9 (4) ◽  
pp. 224-227 ◽  
Author(s):  
Mohamed Abdel-Rohman
Keyword(s):  
Time Delay ◽  
Active Control ◽  
Theoretical Consideration ◽  
Structural Control ◽  
Control Mechanism ◽  
Structural Response ◽  
Delay Effect ◽  
Numerical Example ◽  
Control Forces ◽  
Time Delay Effect

The time delay between measuring the structural response, and applying the designed active control forces may affect the controlled response of the structure if not taken into consideration. In this paper it is shown how to design the control forces to compensate for the delay effect. It is also shown that the time delay effect can be used as a criterion to judge the effectiveness of the proposed control mechanism. As an illustration of the theoretical consideration, a numerical example in which a tall building is controlled by means of active tendons is presented.

Application of PID in Controllable Pitch Propeller of a Multipurpose Ocean Tug

2013 ◽  
Vol 464 ◽  
pp. 253-257
Author(s):  
Hui Fang Chen
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Automatic Control System ◽  
High Reliability ◽  
Control Process ◽  
Good Control ◽  
Control Performance ◽  
Hardware Configuration ◽  
Design Idea ◽  
And Control

This paper takes the automatic control system of controllable pitch propeller in a multipurpose ocean tug as an example to describe the application of the S7-200 series PLC in the control system of 4500 horse power controllable pitch propeller in detail. The principle of control system is addressed, as well as the hardware configuration, the design idea of the main software and control process. The system shows high reliability, accuracy and good control performance in practical in practical running.

Seismic Control Effect for Nonlinear Benchmark Building Using Passive or Semi-Active Damper

2002 ◽  
Author(s):  
Akira Fukukita ◽  
Tomoo Saito ◽  
Keiji Shiba
Keyword(s):  
Active Control ◽  
Passive Control ◽  
Feedforward Control ◽  
Electrical Power ◽  
Control Device ◽  
Control Effect ◽  
Damping Force ◽  
Active Device ◽  
Seismic Control ◽  
Control Forces

We study the control effect for a 20-story benchmark building and apply passive or semi-active control devices to the building. First, the viscous damping wall is selected as a passive control device which consists of two outer plates and one inner plate, facing each other with a small gap filled with viscous fluid. The damping force depends on the interstory velocity, temperature and the shearing area. Next, the variable oil damper is selected as a semi-active control device which can produce the control forces by little electrical power. We propose a damper model in which the damping coefficient changes according to both the response of the damper and control forces based on an LQG feedback and feedforward control theory. It is demonstrated from the results of a series of simulations that the both passive device and semi-active device can effectively reduce the response of the structure in various earthquake motions.

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