Journal articles: 'Servo and regulatory control'

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Ahmad, A., and A. Wahid. "APPLICATION OF MODEL PREDICTIVE CONTROL (MPC) TUNING STRATEGY IN MULTIVARIABLE CONTROL OF DISTILLATION COLUMN." Reaktor 11, no. 2 (2007): 66. http://dx.doi.org/10.14710/reaktor.11.2.66-70.

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A model predictive control strategy is proposed for multivariable nonlinear control problem in a distillation column. The aim is to provide a solution to nonlinear control problem that is favorable in terms of industrial implementation. The scheme utilizes multiple linear models to cover wider range of operating conditions. Depending on the operating conditions, suitable model is used in control computations. Servo and regulatory controls of the system are examined. Comparisons are made to conventional controllers. The results confirmed the potentials of the proposed strategy.

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Zeng, Meng Xiong, and Wen Ouyang. "CNC Servo System Base on PMSM." Applied Mechanics and Materials 331 (July 2013): 267–70. http://dx.doi.org/10.4028/www.scientific.net/amm.331.267.

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The paper study object is the CNC servo system, and it presented three closed-loops control strategy based on PMSM. Through dynamic mathematical model of current loop, rotational speed loop and position loop were established and simplified. The closed-loop regulator was designed. The system was corrected by the controller. The simulation, tuning and calculation of the closed-loop were carried in MATLAB/SIMULINK. The results indicated that the system design was correct, and the desired effect of control was achieved.

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Ngadengon, R., Y. M. Sam, J. H. S. Osman, and R. Tomari. "Discrete Integral Sliding Mode Control for Motion Servo System." Applied Mechanics and Materials 793 (September 2015): 595–99. http://dx.doi.org/10.4028/www.scientific.net/amm.793.595.

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This paper presents a discrete integral sliding mode control (DISMC) to control motion servo system. In DISMC, the order of the motion equation is equal to the order of original system. The past value of the disturbance is taken as the estimate of its present value. The controller is designed to be capable to achieve tracking even for the uncertain system. The designed controller will be compared with Linear Quadratic Regulator (LQR) and discrete Proportional Integral derivative (PID) controller to observe the capability for controlling the system. Simulations demonstrate that the DISMC is highly robust to control although exist uncertainties in the system.

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Kuang, Zhi Quan. "Study on Spindle Servo Control of Four-Axis Vertical CNC Machining Center." Advanced Materials Research 317-319 (August 2011): 83–87. http://dx.doi.org/10.4028/www.scientific.net/amr.317-319.83.

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This paper studies swinging rule of the fourth spindle in Four-axis vertical CNC machining center relying on the vertical axis head. Through current regulator, the speed regulator and improved single neuron PID speed controller the servo control system model is realized. Test results show that good performance is reached according to design of servo control system. The best is to read these instructions and follow the outline of this text.

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Kano, Manabu, Shinji Hasebe, Iori Hashimoto, and Hiromu Ohno. "Extension of Model Predictive Control for Solving Servo and Regulator Problems." KAGAKU KOGAKU RONBUNSHU 23, no. 3 (1997): 421–27. http://dx.doi.org/10.1252/kakoronbunshu.23.421.

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Leonardi, Fabrizio, José Jaime Da Cruz, and Anselmo Bittar. "Multivarible Robust Control with Time-domain Specifications: Servo and Regulator Problems." Electrical Engineering 89, no. 6 (2006): 461–67. http://dx.doi.org/10.1007/s00202-006-0026-2.

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Govindan, Petchinathan. "Evolutionary algorithms based tuning of PID controller for an AVR system." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 3 (2020): 3047. http://dx.doi.org/10.11591/ijece.v10i3.pp3047-3056.

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In this paper, an evolutionary algorithm based optimization algorithm is proposed with new objective function to design a PID controller for the automatic voltage regulator (AVR) system. The new objective function is proposed to improve the transient response of the AVR control system and to obtain the optimal values of controller gain. In this paper, particle swarm optimization (PSO) and cuckoo search (CS) algorithms are proposed to tune the parameters of a PID controller for the control of AVR system. Simulation results are capable and illustrate the effectiveness of the proposed method. Numerical and simulation results based on the proposed tuning approach on PID control of an AVR system for servo and regulatory control show the excellent performance of PSO and CS optimization algorithms.

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Vijayalakshmi, S., and D. Manamalli. "LPV Modeling and Performance Analysis of Boiler Drum Using IMC-PI Controller." Applied Mechanics and Materials 415 (September 2013): 117–21. http://dx.doi.org/10.4028/www.scientific.net/amm.415.117.

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This paper presents the development of linear parameter varying model and control strategy for Industrial boiler drum. The Boiler drum is modeled using the fundamental mass and energy balance equations and data collected from the real time plant. Based on the open loop response of the Boiler drum, the whole non-linear process is split into 4 approximate linear regions and their respective transfer function models are formed from the input-output data. Since the process is nonlinear in nature, linear transfer function models are developed in each operating regions and they are interpolated to obtain the linear parameter varying model. The LPV model is validated using the real time data. Since a single PI controller for whole process does not satisfy both servo and regulatory performance, a multi-model approach with four PI controllers is implemented for the process. Internal Model Control ( IMC)-PI controller is designed to analysis the servo and regulatory performance of the developed LPV model.

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Matiskova, Darina, and Milan Balara. "Upgrade of the Function Quality of the Machine Tools by the Oscillations Compensation." Applied Mechanics and Materials 718 (December 2014): 116–21. http://dx.doi.org/10.4028/www.scientific.net/amm.718.116.

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The paper deals with the improvement of quality control system harmonic drive with servo applying the method of compensation torque oscillations. The method consists of applying the rejection block. Post documents the oscillatory nature of the system servo-harmonic transmission. Described the reduction block connected to this system suppresses the oscillation of torque, speed and position of the harmonic drive output shaft thereby improving the quality of the regulatory process.The papers solves the problem of torque oscillations of the system which consist of servomotor and harmonic drive. Described rejection filter connected to the input of the system damps oscillations and increases the quality of control.

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Prabhaker Reddy, Ginuga, G. Radhika, and K. Anil. "Control of Continuous Stirred Tank Reactor Using Artificial Neural Networks Based Predictive Control." Advanced Materials Research 550-553 (July 2012): 2908–12. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.2908.

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In this work, a Neural network based predictive controller is analyzed to a non linear continuous stirred tank reactor (CSTR) carrying out series and parallel reactions: A→B→C and 2A→D. In the first step, the neural network model of continuous stirred tank reactor is obtained by Levenburg- Marquard training. The data for the training the network is generated using state space model of continuous stirred tank reactor. The neural network model of continuous stirred tank reactor is used in model predictive controller design. The performance of present neural network based model predictive controller (NNMPC) is evaluated through simulations for servo & regulatory problems of CSTR. The performance of neural network based predictive controller is found to be superior than conventional PI controller for setpoint tracking problems.

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Li, Miao, and Hui Bin Gao. "Research on Servo Controller for High Speed Tracking System." Applied Mechanics and Materials 65 (June 2011): 88–91. http://dx.doi.org/10.4028/www.scientific.net/amm.65.88.

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To meet requirement of swiftness and minimization for the tracking system as well as realize horizontal high accuracy tracking measurement, the automatic servo tracking measurement system has been designed. The two closed loop control, bisection method and compound control have been applied into the system. Experimental results show that the maximum tracking error can be limited to less than 0.5°and the regulator time can be 0.04s. The control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. And these specific mechanical properties indexes are useful to mechanical working to make sure the design can be realization. So the research in this paper has important value to the engineering practice.

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Karthikeyan, R., K. Manickavasagam, Shikha Tripathi, and K. V. V. Murthy. "Neuro-Fuzzy-Based Control for Parallel Cascade Control." Chemical Product and Process Modeling 8, no. 1 (2013): 15–25. http://dx.doi.org/10.1515/cppm-2013-0002.

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Abstract This paper discusses the application of adaptive neuro-fuzzy inference system (ANFIS) control for a parallel cascade control system. Parallel cascade controllers have two controllers, primary and secondary controllers in cascade. In this paper the primary controller is designed based on neuro-fuzzy approach. The main idea of fuzzy controller is to imitate human reasoning process to control ill-defined and hard to model plants. But there is a lack of systematic methodology in designing fuzzy controllers. The neural network has powerful abilities for learning, optimization and adaptation. A combination of neural networks and fuzzy logic offers the possibility of solving tuning problems and design difficulties of fuzzy logic. Due to their complementary advantages, these two models are integrated together to form more robust learning systems, referred to as adaptive neuro-fuzzy inference system (ANFIS). The secondary controller is designed using the internal model control approach. The performance of the proposed ANFIS-based control is evaluated using different case studies and the simulated results reveal that the ANFIS control approach gives improved servo and regulatory control performances compared to the conventional proportional integral derivative controller.

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Zhi, Yongfeng, Gaoshang Li, Qun Song, Ke Yu, and Jun Zhang. "Flight control law of unmanned aerial vehicles based on robust servo linear quadratic regulator and Kalman filtering." International Journal of Advanced Robotic Systems 14, no. 1 (2017): 172988141668695. http://dx.doi.org/10.1177/1729881416686952.

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A new flight control law for unmanned aerial vehicles based on robust servo linear quadratic regulator control and Kalman filtering is proposed. This flight control law has a simple structure with high dependability in engineering. The pitch angle controller, which is designed based on the robust servo linear quadratic regulator control, is given to show the flight control law. Simulation results show that the pitch angle controller works well under noise-free conditions. Finally, Kalman filtering is applied to the pitch angle controller under noisy conditions, and the simulation results show that the proposed method reduces the influence of noise.

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Lu, Jun, Hai Xin Zou, Lie Shen, and Xiang Jun Zou. "Application of Adaptive Fuzzy-PID Control in Servo Spindle Rigid Tapping." Advanced Materials Research 301-303 (July 2011): 1477–81. http://dx.doi.org/10.4028/www.scientific.net/amr.301-303.1477.

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Rigid tapping of NC Tapping center is an electromechanical control system which is strongly nonlinear, uncertain and difficult to precise modeling. It is unavoidable to be affected by some nonlinear and uncertain factors such as friction and mechanical resonance. The traditional control method could not fundamentally solve the contradiction between rapid stability and high stable precision of the system response. As an intelligent control method, fuzzy control is actually a kind of PID regulator, and it exists a strong complementary to PID control in the system dynamic and static characteristics. This paper introduced fuzzy adaptive PID control applied to NC rigid tapping in engineering practice, the control method need not to build the controlled object, using mathematical model of fuzzy reasoning method for the online PID parameters auto-tuning, it met the system well for the rapidity and smoothness of comprehensive index requirement and technical realizability, finally through test platform test, numerical control machine tool actual tapping was validated.

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PARK, KIHEON, and JOSEPH J. BONGIORNO Jr. "Wiener-Hopf design of servo-regulator-type multivariable control systems including feedforward compensation." International Journal of Control 52, no. 5 (1990): 1189–216. http://dx.doi.org/10.1080/00207179008953590.

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Lima, Nádson Murilo Nascimento, Lamia Zuñiga Liñan, Flavio Manenti, Rubens Maciel Filho, Marcelo Embiruçu, and Maria Regina Wolf Maciel. "Advanced Control of a Continuous Solution Copolymerization Process." International Journal of Chemical Engineering 2011 (2011): 1–17. http://dx.doi.org/10.1155/2011/967198.

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A model-based predictive control system is designed for a copolymerization reactor. These processes typically have such a high nonlinear dynamic behavior to make practically ineffective the conventional control techniques, still so widespread in process and polymer industries. A predictive controller is adopted in this work, given the success this family of controllers is having in many chemical processes and oil refineries, especially due to their possibility of including bounds on both manipulated and controlled variables. The solution copolymerization of methyl methacrylate with vinyl acetate in a continuous stirred tank reactor is considered as an industrial case study for the analysis of the predictive control robustness in the field of petrochemical and polymer production. Both regulatory and servo problems scenarios are considered to check tangible benefits deriving from model-based predictive controller implementation.

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Peng, Fei, Zhi Zheng Wu, and Lu Wang. "Adaptive Regulation of Tracking Servo for Next Generation Optical Data Storage Systems." Applied Mechanics and Materials 236-237 (November 2012): 497–502. http://dx.doi.org/10.4028/www.scientific.net/amm.236-237.497.

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The tracking servo control has played an important role in the data storage servo systems. In the next generation optical data storage systems, i.e. the near-field recording system, the tracking error of the servo system should be below 10 nanometers under various unknown situations. However, higher data transfer rate and higher data density make it difficult to maintain the desired tracking precision during normal disk operation. It is proposed in this paper to use an adaptive regulation approach to maintain the tracking error below its desired value, despite unknown track eccentricity and external force disturbance. The performance of the proposed control approach is analyzed and simulation results are presented to illustrate the capability of the proposed adaptive regulator to achieve and maintain the desired tracking precision.

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Sarda, Parikshit, Elijah Hedrick, Katherine Reynolds, Debangsu Bhattacharyya, Stephen E. Zitney, and Benjamin Omell. "Development of a Dynamic Model and Control System for Load-Following Studies of Supercritical Pulverized Coal Power Plants." Processes 6, no. 11 (2018): 226. http://dx.doi.org/10.3390/pr6110226.

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Traditional energy production plants are increasingly forced to cycle their load and operate under low-load conditions in response to growth in intermittent renewable generation. A plant-wide dynamic model of a supercritical pulverized coal (SCPC) power plant has been developed in the Aspen Plus Dynamics® (APD) software environment and the impact of advanced control strategies on the transient responses of the key variables to load-following operation and disturbances can be studied. Models of various key unit operations, such as the steam turbine, are developed in Aspen Custom Modeler® (ACM) and integrated in the APD environment. A coordinated control system (CCS) is developed above the regulatory control layer. Three control configurations are evaluated for the control of the main steam; the reheat steam temperature is also controlled. For studying servo control performance of the CCS, the load is decreased from 100% to 40% at a ramp rate of 3% load per min. The impact of a disturbance due to a change in the coal feed composition is also studied. The CCS is found to yield satisfactory performance for both servo control and disturbance rejection.

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Bogen, D. K., Y. Ariel, T. A. McMahon, and W. H. Gaasch. "Measurement of peak systolic elastance in intact canine circulation with servo pump." American Journal of Physiology-Heart and Circulatory Physiology 249, no. 3 (1985): H585—H593. http://dx.doi.org/10.1152/ajpheart.1985.249.3.h585.

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Peak systolic elastance (Emax) was measured in the intact canine circulation by means of a new experimental technique. In this technique the heart is isolated from the circulation during a single systole and subjected to controlled ventricular loads. An electropneumatic aortic occluder is used to isolate the ventricle, and a servo-controlled syringe pump is used to control the ventricular load. Because the experimental load is applied for a single heartbeat only, ventricular function can be measured without the interference of regulatory feedback mechanisms. In eight dogs, weighing 17-42 kg, the relationship between changes in endsystolic pressure and volume was determined from the single-beat application of purely compliant loads. The end-systolic relations were linear, and their slope, Emax, was inversely related to weight. The observed relation between Emax and body weight allows comparisons to be made between different preparations in which Emax has been determined. Values of Emax obtained from the single-beat preparation were found to be 27-74% above those reported in isolated heart preparations and nearly identical to those reported for in vivo or denervated in situ preparations.

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Syahroni, Nanang, and Jae Weon Choi. "An Autonomous Underwater Vehicle Simulation Using Linear Quadratic Servo Based on Open Control Platform." Modelling and Simulation in Engineering 2012 (2012): 1–4. http://dx.doi.org/10.1155/2012/291318.

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This paper presents an optimal regulator for depth control simulation of an autonomous underwater vehicle (AUV) using a new approach of decentralized system environment called open control platform (OCP). Simulation results are presented to demonstrate performance of the proposed method.

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Salahuddin, Nazratul Fareha, Ahmad Shamiri, Mohd Azlan Hussain, and Navid Mostoufi. "Fuzzy-GMC Control of Gas-Phase Propylene Copolymerization in Fluidized Bed Reactor." MATEC Web of Conferences 156 (2018): 07002. http://dx.doi.org/10.1051/matecconf/201815607002.

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A modified two-phase model for gas phase propylene and ethylene copolymerization was chosen to represent the process in a fluidized bed reactor. This model considered the entrainment of solid particles in the reactor, as a modification to the original two-phase model assumptions. The non-linearity of this process makes it difficult to control just by using conventional controller such as PID. A hybrid control strategy (a simple designed fuzzy logic controller (FLC) integrated with generic model control (GMC)) is designed to control the temperature of the reactor. This advanced control system was compared with the GMC and conventional PID controller. The simulation results showed that the hybrid controller (Fuzzy-GMC) performed better than both GMC and PID in terms of both servo and regulatory control.

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Fontes, C. H., and M. J. Mendes. "Nonlinear predictive control of an industrial slurry reactor." Sba: Controle & Automação Sociedade Brasileira de Automatica 19, no. 4 (2008): 417–30. http://dx.doi.org/10.1590/s0103-17592008000400005.

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A nonlinear model predictive control (NMPC) is applied to a slurry polymerization stirred tank reactor for the production of high-density polyethylene. Its performance is examined to reach the required mean molecular weight and comonomer composition, together with the temperature setpoint. A complete phenomenological model including the microscale, the mesoscale and the macroscale levels was developed to represent the plant. The control algorithm comprises a neural dynamic model that uses a neural network structure with a feedforward topology. The algorithm implementation considers the optimization problem, the manipulated and controlled variables adopted and presents results for the regulatory and servo problems, including the possibility of dead time and multi-rate sampling in the controlled variables. The simulation results show the high performance of the NMPC algorithm based in a model for one-step ahead prediction only, and, at the same time, attests the strong difficulty to control polymer properties with dead time in their measurements.

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Ramelan, Agus, Arief Syaichu Rohman, and Allen Kelana. "Embedded Position Control of Permanent Magnet Synchronous Motor Using Model Predictive Control." MATEC Web of Conferences 198 (2018): 04007. http://dx.doi.org/10.1051/matecconf/201819804007.

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This paper presents an implementation embedded system for position control of Permanent Magnet Synchronous Motor (PMSM). The control system consists of raspberry pi 3 as a microcontroller, ASDA-A2 servo drive, and Delta Servo ECMA type. The software design includes simulation tool and Python included on Raspbian OS. Communication between Raspberry Pi 3 and ASDA-A2 drivers using the ASCII Modbus communication protocol. Raspberry Pi 3 processes the reference data and the actual reading result and calculates the resulting error. The control algorithm used in this research is Model Predictive Control (MPC). As a Linear Quadratic Regulator, MPC aims to design and generate an optimal control signal with the ability to anticipate saturation, receding horizon, future event and take control accordingly In the design of the MPC technique to adjust the speed of the PMSM to take action of reference tracking, performance index optimization is done by adjusting the value of weighting horizon N, Q and R. The simulation and implementation results showed that the PMSM can reach the stability point on each desired setpoint and result in a near-zero steady-state error.

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Begum, K. Ghousiya. "Performance assessment of controller designed for electrical systems with second order dynamics." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 39, no. 6 (2020): 1345–62. http://dx.doi.org/10.1108/compel-05-2020-0175.

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Purpose An assessment technique that analyzes the servo and regulatory characteristics of the proportional integral derivative controller is designed for time-delayed second-order stable processes. Design/methodology/approach The minimum theoretical error expression for integral of the absolute errors (IAE_o) is obtained from the preferred servo and regulatory transfer functions dependent on the step changes in reference and load variables. Findings The error-based index is outlined to estimate the controller that is derived using internal model-based control or direct synthesis method. The ratio between derived IAE_o and the IAE_actual gained from the loop response that experiences step input variations gives rise to a dimensionless error index. This error index measures the behaviour of the controller by considering the index value. If the error index value is larger than 0.8, then the effort taken by the controller is good or else retuning is expected. Originality/value The efficacy of the index to validate the controller is verified by applying on a few second-order electrical processes. The results are simulated for both reference tracking and load rejection tasks to demonstrate the rationality of the presented index.

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Siu, K. L., J. M. Ahn, and K. H. Chon. "Electrohydraulic pump-driven closed-loop blood pressure-regulatory system." American Journal of Physiology-Renal Physiology 296, no. 6 (2009): F1530—F1536. http://dx.doi.org/10.1152/ajprenal.90756.2008.

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In this paper, we describe our design for a new electrohydraulic (EH) pump-driven renal perfusion pressure (RPP)-regulatory system capable of implementing precise and rapid RPP regulation in experimental animals. Without this automated system, RPP is manually controlled via a blood pressure clamp, and the imprecision in this method leads to compromised RPP data. This motivated us to develop an EH pump-driven closed-loop blood pressure regulatory system based on flow-mediated occlusion using the vascular occlusive cuff technique. A closed-loop servo-controller system based on a proportional plus integral (PI) controller was designed using the dynamic feedback RPP signal from animals. In vivo performance was evaluated via flow-mediated RPP occlusion, maintenance, and release responses during baseline and ANG II-infused conditions. A step change of −30 mmHg, referenced to normal RPP, was applied to Sprague-Dawley rats with the proposed system to assess the performance of the PI controller. The PI's performance was compared against manual control of blood pressure clamp to regulate RPP. Rapid RPP occlusion (within 3 s) and a release time of ∼0.3 s were obtained for the PI controller for both baseline and ANG II infusion conditions, in which the former condition was significantly better than manual control. We concluded that the proposed EH RPP-regulatory system could fulfill in vivo needs to study various pressure-flow relationships in diverse fields of physiology, in particular, studying the dynamics of the renal autoregulatory mechanisms.

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Zhong, Chong-Quan, Lin Wang, and Chuan-Fang Xu. "Path Tracking of Permanent Magnet Synchronous Motor Using Fractional Order Fuzzy PID Controller." Symmetry 13, no. 7 (2021): 1118. http://dx.doi.org/10.3390/sym13071118.

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Permanent magnet synchronous motor (PMSM) AC servo system has the characteristics of uncertainty, time-varying, nonlinear and fractional order. Applying the traditional control method is difficult to achieve the desired control effect. The fuzzy control has strong adaptability to the parameter change, nonlinearity and imprecise model of the controlled object. The simulation model of permanent magnet synchronous motor three closed-loop systems is established. The control principle and the realization of space vector pulse width modulation (SVPWM) are studied by using a vector control strategy. Due to the fractional-order characteristic of the motor, a fuzzy logic algorithm is used to realize the parameter self-tuning of the fractional-order proportional integral differential (PID) controller. The controller is selected as the position regulator of the servo motor. It combines the precision of fractional-order PID controller with the adaptability of fuzzy control and adds feed-forward to improve the response speed. The path tracking experiments on several different paths are carried out, and the results show that the control method is effective and can meet the trajectory tracking requirements of servo control. Finally, the speed and position tracking test of the PMSM AC servo system is carried out on the test verification platform, which verifies the effectiveness of the control algorithm.

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Ning, Chen Xiao, Xu She Zhang, Fei Zhu, and Lan Li. "The Design of Flying-Sawing Machine Control System Based on Fuzzy Control." Applied Mechanics and Materials 201-202 (October 2012): 119–22. http://dx.doi.org/10.4028/www.scientific.net/amm.201-202.119.

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The traditional PID regulator can get a satisfactory control effect in many situations. But because of the welded pipe servo cutting system characteristics with not fixed the parameter, variable, strong nonlinear and coupling complex, it is difficult to obtain ideal response in different time, and it is also hard to adapt changes in the environment and the uncertainty of the system. In allusion to the defect of the traditional PID regulator in the welded pipe cutting machine, it is put forward the parameter self-setting fuzzy PID adjustment method and a kind of fuzzy reasoning control rule in this paper. According to the rule, a welded pipe cutting machine control system mathematical model is established and numerical simulation of tailing after the given order jump curve in adaptive fuzzy PID regulator is finished. The simulation results show that: the system response speed is faster than before, the system adjusting precision and stability become well. All of this is hard to realize from traditional PID.

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Sanko, A. A., A. A. Sheinikov, T. A. Tishchenko, and D. A. Smolskiy. "The use of the localization method for calculation of the robust PID regulator parameters for unmanned aircraft servo motor." Civil Aviation High Technologies 23, no. 1 (2020): 95–105. http://dx.doi.org/10.26467/2079-0619-2020-23-1-95-105.

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The problem of controlling a typical nonlinear servo motor of an unmanned aercraft with non-stationary parameters using a robust PID controller is considered. The procedure for calculating the parameters of a robust PID controller based on the localization method (further - LM PID controller) for continuous and discrete control systems is studied. The influence of disturbing factors (internal and external) acting on the servo motor is considered. It is established that the main perturbations acting on the servo drive include internal perturbations, which are changes in the time constant and its gain from the temperature of the environment and the quality of the supply voltage. The simulation in the class of linear and nonlinear continuous systems showed that a servo drive with a ML PID controller has the property of robustness in the working range of changes in both the input signal and the parameters of the servo drive and controller. Simulation results showing the research are presented. When describing a servo motor with an LM PID controller in the class of linear discrete systems, its robustness is limited by a narrow range of variation of both its parameters and the quantization period of the input signal. As the degree of uncertainty in the parameters of the servo motor increases (approaching the working range of their change), the discrete system loses stability. For the synthesis of robust control circuits of an unmanned aercraft with given characteristics, mathematical dependences of the settling time and static error of a typical servo motor with LM PID controller from the quantization period of the input signal and the degree of uncertainty in its parameters are presented.

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Shen, Liang Yuan, Hong Guang Wang, Rui Jun Zhang, and Peng Peng Liu. "Feedback Servo Pump Station Overflow Innovative Energy-Saving Design." Advanced Materials Research 341-342 (September 2011): 452–55. http://dx.doi.org/10.4028/www.scientific.net/amr.341-342.452.

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The usual hydraulic pump station pumps the general use of quantitative supply voltage level or constant pressure, using the corresponding control valve speed to adapt to work requirements, when the hydraulic system is intermittent or low-load condition, a large number of high-pressure oil through regulator overflow Back to the tank overflow valve, causing a great deal of energy consumption, when the hydraulic system requires a large flow of oil, it will result in a short time for the fluid system for liquid inadequate and under-voltage phenomenon. To solve this problem, we propose to improve the program, and conducted the analysis and comparison of several options to determine the source of energy-saving adaptive overall scheme of oil, its reasonable design, implementation of the automatic adaptive functioning, energy loss Small, the effect is significant.

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Goyal, Vishal, Puneet Mishra, Aasheesh Shukla, Vinay Kumar Deolia, and Aarti Varshney. "A fractional order parallel control structure tuned with meta-heuristic optimization algorithms for enhanced robustness." Journal of Electrical Engineering 70, no. 1 (2019): 16–24. http://dx.doi.org/10.2478/jee-2019-0002.

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Abstract This paper studies an improved fractional order parallel control structure (FOPCS) for enhancing the robustness in an industrial control loop having a first order process with dead time along with its tuning aspects. Since inclusion of fractional order calculus also increase the number of parameters to be determined for a particular control loops, tuning becomes an essential task. Four different tuning methods are considered to optimize the gains of parallel control structure (PCS) and FOPCS. Integral of time weighted absolute error for servo and regulatory problems along with overshoot value have been considered for performance evaluation. Extensive simulation studies including change in setpoint and mismatch in processmodel parameters have been carried out. On the basis of these studies, it was observed that FOPCS tuned by backtracking search algorithm, outperformed all other controllers in terms of considered performance measures.

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Zhu, Zhiying, Yukun Sun, and Ye Yuan. "Decoupling Control for Dual-Winding Bearingless Switched Reluctance Motor Based on Improved Inverse System Method." Mathematical Problems in Engineering 2017 (2017): 1–17. http://dx.doi.org/10.1155/2017/5853423.

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Dual-winding bearingless switched reluctance motor (BSRM) is a multivariable high-nonlinear system characterized by strong coupling, and it is not completely reversible. In this paper, a new decoupling control strategy based on improved inverse system method is proposed. Robust servo regulator is adopted for the decoupled plants to guarantee control performances and robustness. A phase dynamic compensation filter is also designed to improve system stability at high-speed. In order to explain the advantages of the proposed method, traditional methods are compared. The tracking and decoupling characteristics as well as disturbance rejection and robustness are deeply analyzed. Simulation and experiments results show that the decoupling control of dual-winding BSRM in both reversible and irreversible domains can be successfully resolved with the improved inverse system method. The stability and robustness problems induced by inverse controller can be effectively solved by introducing robust servo regulator and dynamic compensation filter.

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Manonmani, A., T. Thyagarajan, M. Elango, and S. Sutha. "Modelling and control of greenhouse system using neural networks." Transactions of the Institute of Measurement and Control 40, no. 3 (2016): 918–29. http://dx.doi.org/10.1177/0142331216670235.

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A greenhouse system (GHS) is a closed structure that facilitates modified growth conditions to crops and provides protection from pests, diseases and adverse weather. However, a GHS exhibits non-linearity due to the interaction between the biological subsystem and the physical subsystem. Non-linear systems are difficult to control, particularly when their characteristics change with time. These systems are best handled with methods of computation intelligence, such as artificial neural networks (ANNs) and fuzzy systems. In the present work, the approximation capability of a neural network is used to model and control sufficient growth conditions of a GHS. An optimal neural network-based non-linear auto regressive with exogenous input (NARX) time series model is developed for a GHS. Based on the NARX model, two intelligent control schemes, namely a neural predictive controller (NPC) and non-linear auto regressive moving average (NARMA-L2) controller are proposed to achieve the desired growth conditions such as humidity and temperature for a better yield. Finally, closed-loop performances of the above two control schemes for servo and regulatory operations are analysed for various operating conditions using performance indices.

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Miller, Susan M., Christopher Witko, and Neal D. Woods. "How the Unorganized Mass Public (Sometimes) Gets Represented in Regulatory Politics." Political Research Quarterly 71, no. 1 (2017): 88–101. http://dx.doi.org/10.1177/1065912917724005.

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Many scholars have argued that because consumers are poorly organized, regulatory enforcement will tend to be lax and serve the interests of industry. Considering, however, that elections are one of the main mechanisms by which the public exerts control over policy, surprisingly few studies have examined how electoral incentives may spur the government to regulate vigorously on behalf of consumers. We argue that when the threat of electoral accountability is greater, regulatory activities will serve the interests of the public, even if they impose costs on industry. We test this theoretical expectation by analyzing state regulatory activity in the wake of exogenous storms and natural disasters, which provide us with important theoretical and causal leverage. We find that a more “pro-regulation” electorate and elected chief regulators acting in close proximity to elections are associated with pro-consumer regulatory action.

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Derets, O., A. Sadovoi, and A. Derets. "OPTIMIZATION IN SPEED OF THE RELAY-MODAL CONTROL SYSTEM OF THE SERVO DRIVE BASED ON THE STUDY OF THE MATHEMATICAL MODEL." Collection of scholarly papers of Dniprovsk State Technical University (Technical Sciences) 2, no. 37 (2021): 43–48. http://dx.doi.org/10.31319/2519-2884.37.2020.8.

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Positional control systems are characterized by the limitation of intermediate coordinates in transients. Such restrictions are implemented by a system with cascading controllers. The N-i switching method provides optimization of the speed of such control systems. In this paper, we study the three-loop system of subordinate regulation. The parameters of the relay-modal controllers were varied based on a change in the calculated amplitude of the control action without changing its real value. The parametric synthesis of such a system is based on optimal trajectories in terms of speed. The study of the control system at various settings revealed a different degree of deviation of transitional trajectories from the calculated one. This effect is due to the replacement of optimal regulator settings with modal ones in order to give the system a margin of stability. The obtained families of transient characteristics make it possible to construct empirical dependences of the duration of regulation on the relative value of the calculated amplitude of the control action. Such dependencies have pronounced extremes, which makes it possible to tune the system to a near optimal speed by preventing the regulators from entering the sliding mode prematurely. The performed simulation of the positional system with extremal settings confirms the effectiveness of the proposed methodology for the correction of dynamic characteristics. The results of the study open up the prospects of the practical implementation of relay-modal control algorithms for cascading systems, the synthesis of which is based on the N-i switching method.

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Casaca, Ana, Gabriel M. Hauswirth, Heidi Bildsoe, Moisés Mallo, and Edwina McGlinn. "Regulatory landscape of the Hox transcriptome." International Journal of Developmental Biology 62, no. 11-12 (2018): 693–704. http://dx.doi.org/10.1387/ijdb.180270em.

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Precise regulation of Hox gene activity is essential to achieve proper control of animal embryonic development and to avoid generation of a variety of malignancies. This is a multilayered process, including complex polycistronic transcription, RNA processing, microRNA repression, long noncoding RNA regulation and sequence-specific translational control, acting together to achieve robust quantitative and qualitative Hox protein output. For many such mechanisms, the Hox cluster gene network has turned out to serve as a paradigmatic model for their study. In this review, we discuss current knowledge of how the different layers of post-transcriptional regulation and the production of a variety of noncoding RNA species control Hox output, and how this shapes formation of developmental systems that are reproducibly patterned by complex Hox networks.

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Srisuddee, Sura, Malinee Sriariyanun, Chanin Panjapornpon, and Atthasit Tawai. "Input/output Linearization Control Technique for Anaerobic Digestion Reactor with Recirculation." E3S Web of Conferences 141 (2020): 01007. http://dx.doi.org/10.1051/e3sconf/202014101007.

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Anaerobic digestion (AD) process has been generally applied in factories for wastewater treatment and energy recovery. For the AD processes, the continuously stirred tank reactor (CSTR) with recirculation are typically applied in industries for methane production from wastewater treatment. Since the recycle stream affects the inlet concentration of the reactor, the control performance of traditional PI and PID controllers used to manipulate control actuators may be limited. Additionally, the process control loops related to biochemical reactions are generally employed the operational experiences without process dynamic consideration. A control system based on input/output (I/O) linearization control technique for an anaerobic digestion (AD) process was developed in this work. The control system applied the concept of the I/O linearization technique, which followed dynamic behaviors of the reactor with a two-step (acidogenesis-methanogenesis) kinetic model. The volatile fatty acid (VFA) concentration was regulated by manipulation of the dilution rate to achieve the requested trajectories. Control performances of the closed-loop system were investigated by a simulation under servo and regulatory problems. The simulation results showed that the developed control scheme successfully forced the controlled output to achieve the desired set points and handled the introduced control problems.

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Almeida, Alexandre Marques de, Marcelo Kaminski Lenzi, and Ervin Kaminski Lenzi. "A Survey of Fractional Order Calculus Applications of Multiple-Input, Multiple-Output (MIMO) Process Control." Fractal and Fractional 4, no. 2 (2020): 22. http://dx.doi.org/10.3390/fractalfract4020022.

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Multiple-input multiple-output (MIMO) systems are usually present in process systems engineering. Due to the interaction among the variables and loops in the MIMO system, designing efficient control systems for both servo and regulatory scenarios remains a challenging task. The literature reports the use of several techniques mainly based on classical approaches, such as the proportional-integral-derivative (PID) controller, for single-input single-output (SISO) systems control. Furthermore, control system design approaches based on derivatives and integrals of non-integer order, also known as fractional control or fractional order (FO) control, are frequently used for SISO systems control. A natural consequence, already reported in the literature, is the application of these techniques to MIMO systems to address some inherent issues. Therefore, this work discusses the state-of-the-art of fractional control applied to MIMO systems. It outlines different types of applications, fractional controllers, controller tuning rules, experimental validation, software, and appropriate loop decoupling techniques, leading to literature gaps and research opportunities. The span of publications explored in this survey ranged from the years 1997 to 2019.

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Feng, Yong Jian, Ming Hong, and Xiao Wei Huo. "The Electric-Hydraulic Servo Equipment for the Real Force and Motion Simulation of Pumping Unit." Advanced Materials Research 346 (September 2011): 889–95. http://dx.doi.org/10.4028/www.scientific.net/amr.346.889.

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In this paper, new type electro-hydraulic servo equipment is given for testing the working feature on pumping unit. It is the key to get the real simulation of motion and loading of pumping unit. The equipment in paper can be used to repeat all kind of the real force and motion on pumping unit. In order to get better simulation results, the algorithm for self-adaptation control with Kalman filter, which is used for error-free estimate of motion state in order to obtain high accuracy, is applied to solve powerful motion error—surplus force in passive loading system . All algorithms can be used in computer. Last, the test results of pumping unit loading are given. By actual use，the results show that self-adaptation control model with Kalman filter are used for decreasing error by motion of loading system is feasible and the control model can automatically regulate coefficients of regulator.

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Alcántara, S., R. Vilanova, and C. Pedret. "PID control in terms of robustness/performance and servo/regulator trade-offs: A unifying approach to balanced autotuning." Journal of Process Control 23, no. 4 (2013): 527–42. http://dx.doi.org/10.1016/j.jprocont.2013.01.003.

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Kano, Manabu, Hiromu Ohno, Shinji Hasebe, Iori Hashimoto, Kazuro Kurihara, and Toshiyuki Sakamoto. "Extended Model Predictive Control Algorithm for Solving Servo and Regulator Problems and its Application to a Reverberating Furnace." IFAC Proceedings Volumes 30, no. 9 (1997): 697–702. http://dx.doi.org/10.1016/s1474-6670(17)43228-9.

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Irianto, Irianto, Suhariningsih Suhariningsih, and Viviana Ratna Dewanti. "Rancang Bangun Alat Pengering Pelepah Pisang(Menggunakan Metode Controller Chien Regulator I dan Chien Servo I Sebagai Tuning Kontrol PI)." JEEE-U (Journal of Electrical and Electronic Engineering-UMSIDA) 2, no. 1 (2018): 1–7. http://dx.doi.org/10.21070/jeee-u.v2i1.1091.

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Bananas provide many health benefits because they have enough vitamin A for daily body vitamins. Benefits of bananas are not only found in the fruit alone. Banana stem is rarely used because it is considered not to have more benefits and is only considered as waste. However, banana stem can be transformed into various forms of beautiful crafts and high economic value. Banana banana is dried first before being processed into various handicrafts. The process of drying banana is very dependent on the weather conditions and the heat of the sun. Conventional banana drying process takes approximately 70 hours with a solar temperature of about 40oC. The solution to this problem is, design and manufacture a microcontroller based banana bum dryer using PI control to regulate the temperature and utilize the heater as an alternative heat source. This PI control uses Chien Regulator I and Chien Servo I tuning methods. In this Final Project, temperature and banana moisture content is measured. The control will adjust the exhaust fan when the temperature read by LM35 is displayed on LCD 4x20 for temperature monitoring. To adjust the AC-AC voltage controller voltage on the heater, depending on the angle of ignition of the TCA785 IC. DAC of Microcontroller ATMega16 will convert the digital data released microcontroller into analog voltage. The Kp and Ki values used are Kp = 5 and Ki 0.625 using Chien Regulator I method and Kp = 4,126 and Ki 0.414 using Chien Servo I method The drying process takes 16 hours with water content of 4.76% at ± 65oC using Chien Servo I method because the temperature response is more stable.

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Ramasamy, Subramanian, and Sahjendra N. Singh. "Biology-Inspired Robust Dive Plane Control of Non-Linear AUV Using Pectoral-Like Fins." Applied Bionics and Biomechanics 7, no. 2 (2010): 153–68. http://dx.doi.org/10.1155/2010/140148.

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The development of a control system for the dive plane control of non-linear biorobotic autonomous underwater vehicles, equipped with pectoral-like fins, is the subject of this paper. Marine animals use pectoral fins for swimming smoothly. The fins are assumed to be oscillating with a combined pitch and heave motion and therefore produce unsteady control forces. The objective is to control the depth of the vehicle. The mean angle of pitch motion of the fin is used as a control variable. A computational-fluid-dynamics-based parameterisation of the fin forces is used for control system design. A robust servo regulator for the control of the depth of the vehicle, based on the non-linear internal model principle, is derived. For the control law derivation, an exosystem of third order is introduced, and the non-linear time-varying biorobotic autonomous underwater vehicle model, including the fin forces, is represented as a non-linear autonomous system in an extended state space. The control system includes the internal model of ak-fold exosystem, wherekis a positive integer chosen by the designer. It is shown that in the closed-loop system, all the harmonic components of order up tokof the tracking error are suppressed. Simulation results are presented which show that the servo regulator accomplishes accurate depth control despite uncertainties in the model parameters.

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Pan, Rui, Guiping Lin, Zhigao Shi, Yu Zeng, and Xue Yang. "The Application of Disturbance-Observer-Based Control in Breath Pressure Control of Aviation Electronic Oxygen Regulator." Energies 14, no. 16 (2021): 5189. http://dx.doi.org/10.3390/en14165189.

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The electronic oxygen regulator (EOR) is a new type of aviation oxygen equipment which uses electronic servo control technology to control breathing gas pressure. In this paper, the control method of EOR was studied, and the dynamic model of the aviation oxygen system was established. A disturbance-observer-based controller (DOBC) was designed by the backstepping method to achieve the goal of stable and fast breath pressure control. The sensitivity function was proposed to describe the effect of inspiratory flow on breath pressure. Combined with the frequency domain analysis of the input sensitivity function, the parameters of the DOBC were analyzed and designed. Simulation and experiment studies were carried out to examine the control performance of DOBC in respiratory resistance and positive pressurization process under the influence of noise and time delay in the discrete electronic control system, which could meet the aviation physiology requirements. The research results not only verified the rationality of the application of DOBC in the breath control of EOR, but also proved the effectiveness of the control parameters design method according to the frequency domain analysis, which provided an important design basis for the subsequent study of EOR.

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Aydogdu, Omer, and Mehmet Latif Levent. "State Estimation with Reduced-Order Observer and Adaptive-LQR Control of Time Varying Linear System." Elektronika ir Elektrotechnika 26, no. 2 (2020): 24–31. http://dx.doi.org/10.5755/j01.eie.26.2.25873.

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In this study, a new controller design was created to increase the control performance of a variable loaded time varying linear system. For this purpose, a state estimation with reduced order observer and adaptive-LQR (Linear–Quadratic Regulator) control structure was offered. Initially, to estimate the states of the system, a reduced-order observer was designed and used with LQR control method that is one of the optimal control techniques in the servo system with initial load. Subsequently, a Lyapunov-based adaptation mechanism was added to the LQR control to provide optimal control for varying loads as a new approach in design. Thus, it was aimed to eliminate the variable load effects and to increase the stability of the system. In order to demonstrate the effectiveness of the proposed method, a variable loaded rotary servo system was modelled as a time-varying linear system and used in simulations in Matlab-Simulink environment. Based on the simulation results and performance measurements, it was observed that the proposed method increases the system performance and stability by minimizing variable load effect.

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Olojede, Paul, Francis Iyoha, Ben-Caleb Egbide, and Olayinka Erin. "Regulatory agencies and creative accounting practices in Nigeria." Problems and Perspectives in Management 18, no. 3 (2020): 465–78. http://dx.doi.org/10.21511/ppm.18(3).2020.38.

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Regulation and regulatory agencies are to serve as external control mechanisms to ensure that the financial statements provide a fair view of the company’s operating performance and financial position, free of any unethical practice and suitable for all stakeholders’ needs. Despite the increasing importance of regulatory agencies in enforcing compliance with the standards and laws, it occupies a limited space in accounting research. This study, therefore, investigated the impact of regulatory agencies on creative accounting practices. The study used descriptive and survey research design to achieve its aim. It employed a multi-stage sampling technique, also questionnaires were distributed among 405 respondents consisting of preparers of accounts, users of accounts, and regulators. Out of the number distributed, the respondents returned 241 copies, and all of them were found suitable. The study used Ordinary Least Squares (OLS) to analyze the data and test the hypothesis. The empirical findings showed that the regulatory agencies jointly show a significant impact on creative accounting practices, but the level of contribution to the overall impact by each regulatory agency varies. The study concludes that Nigeria’s regulatory agencies are weak and inefficient in enforcing compliance with the relevant rules. The study recommends that the institutional capacity of the regulatory agencies should be strengthened by enforcing compliance with financial reporting rules and regulation. Most of these agencies should develop capacity in the areas of manpower, information technology infrastructures, and funding. Acknowledgment The authors acknowledge Covenant University who has solely provided the platform for this research and has also fully sponsored the research cluster search for data across the country.

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Lu, Wan Yin. "Fuzzy Controller of Voltage Regulator System BP Neural Network Model Design and Simulation." Applied Mechanics and Materials 331 (July 2013): 277–80. http://dx.doi.org/10.4028/www.scientific.net/amm.331.277.

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Voltage regulation control system is a typical position servo system, its often uses PID regulation control, the adjustment time is long, big overshoot. This research through the output signal and a given signal of the deviation and its differential data analysis, design of fuzzy controller to realize the fuzzy control of this system. Fuzzy controller of the thought and method in microcomputer realization difficulty is very great, the calculation is not easy.Consider BP network model is certain function relation, the exponential computation in microcomputer such as PLC in the corresponding instruction, BP network model is easy to through the programming realization, through the simulation BP network model control effect and the fuzzy controller control effect anastomosis.

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Taylor, Katarzyna, and Krzysztof Sobczak. "Intrinsic Regulatory Role of RNA Structural Arrangement in Alternative Splicing Control." International Journal of Molecular Sciences 21, no. 14 (2020): 5161. http://dx.doi.org/10.3390/ijms21145161.

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Alternative splicing is a highly sophisticated process, playing a significant role in posttranscriptional gene expression and underlying the diversity and complexity of organisms. Its regulation is multilayered, including an intrinsic role of RNA structural arrangement which undergoes time- and tissue-specific alterations. In this review, we describe the principles of RNA structural arrangement and briefly decipher its cis- and trans-acting cellular modulators which serve as crucial determinants of biological functionality of the RNA structure. Subsequently, we engage in a discussion about the RNA structure-mediated mechanisms of alternative splicing regulation. On one hand, the impairment of formation of optimal RNA structures may have critical consequences for the splicing outcome and further contribute to understanding the pathomechanism of severe disorders. On the other hand, the structural aspects of RNA became significant features taken into consideration in the endeavor of finding potential therapeutic treatments. Both aspects have been addressed by us emphasizing the importance of ongoing studies in both fields.

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Viteckova, Miluse, and Antonin Vitecek. "2DOF Controller Tuning." International Journal of Engineering Research in Africa 18 (October 2015): 57–64. http://dx.doi.org/10.4028/www.scientific.net/jera.18.57.

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At present the two degrees of freedom (2DOF) controllers are more often available. These controllers enable to tune both from point of view of the desired variable and the disturbance variable as well. It allows increase the overall quality of control. For the tuning of the 2DOF controllers to date there are only a few suitable methods. This paper is devoted to the tuning of the 2DOF PI and PID controllers by the multiple dominant pole method (MDPM) for first order plants and integrating plants with time delay. It is an analytical method and it is shown that by the corresponding tuning of the 2DOF controllers it is possible to obtain the non-oscillatory servo and regulatory step responses without overshoots. The use is demonstrated in the example.

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Giwa, Saidat Olanipekun, Abel Adekanmi Adeyi, and Abdulwahab Giwa. "Application of Model Predictive Control to Renewable Energy Development via Reactive Distillation Process." International Journal of Engineering Research in Africa 27 (December 2016): 95–110. http://dx.doi.org/10.4028/www.scientific.net/jera.27.95.

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Reactive distillation is a process that combines chemical reaction and separation in a single piece of equipment (distillation column). The process has a lot of benefits especially for those reactions occurring at conditions suitable for the distillation of the process components, and these result in significant economic advantages. However, owing to the complexities resulting from the integration of reaction and separation, its control is still a challenge to process engineers because it requires a control method that is robust enough to handle its complexities. Therefore, in this work, model predictive control (MPC) has been applied to a reactive distillation process used for developing a renewable energy known as biodiesel. The control algorithm of the MPC was formulated with the aid of MPC toolbox of MATLAB/Simulink in which the closed-loop models of the process were developed and simulated. The analysis of the results obtained from the simulations carried out for the optimization of the tuning parameters revealed that, among the tuning parameters considered, integral absolute error of the control system was less affected by the control horizon because its p-value was greater than 0.05 based on 95% confidence level. Furthermore, the simulation of the closed-loop system of the process using model predictive control tuned with control horizon of 11, prediction horizon of 18, weight on manipulated variable rate of 0.05 and weight on output variable of 2.17, which were the optimum parameters obtained using Excel Solver, showed that the system was well handled by the controller under servo control because it was able to get settled at desired mole fractions within 60 min. However, the settling time recorded in the case of regulatory control system of the process with the same controller was found not to be encouraging. Therefore, it is recommended that further work should be carried out on this subject matter in an attempt to obtain tuning parameters that will make the settling time of the closed-loop system of the process under regulatory control simulation very reasonable.

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Li, Siming, and Jiandie D. Lin. "Molecular control of circadian metabolic rhythms." Journal of Applied Physiology 107, no. 6 (2009): 1959–64. http://dx.doi.org/10.1152/japplphysiol.00467.2009.

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Circadian metabolic rhythms are fundamental to the control of nutrient and energy homeostasis, as well as the pathogenesis of metabolic disease, such as obesity, lipid disorders, and type 2 diabetes. This temporal organization of tissue metabolism is coordinated through reciprocal cross talk between the biological timing system and the metabolic regulatory networks. In this review, we discuss the signaling mechanisms that serve to couple metabolic regulation to the circadian pacemaker, in particular the role of the peroxisome proliferator-activated receptor-γ coactivator-1 transcriptional coactivators in integrating clock and energy metabolism.

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Journal articles on the topic 'Servo and regulatory control'

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