Experimental Control System Research Articles

Fusion power supply advances by the J-TEXT engineering team

To meet the stringent requirements of the fusion power supply for large-scale fusion devices, the J-TEXT engineering team has carried out key technology research and applications in several important directions of fusion power supply. This article presents the advances made by the J-TEXT engineering team in recent years in the following areas: (1) a high-voltage power supply for an auxiliary heating system; (2) a breakdown protection device for an auxiliary heating power supply; (3) magnetic field compatibility; (4) a high-voltage pulsed power supply for a field-reversed configuration; (5) a large physics experimental facility control system. The research backgrounds, technical progress, test results, applications, summaries and prospects are described in detail in each part. These innovative research results and valuable engineering experience can promote the progress of fusion power supply technology, and also lay a foundation for the development of power supplies with higher parameters in the future.

Development of experimental control system for regenerative heating process of high-speed cryo-adsorption pump

The vacuum system of the Negative-ion-based Neutral Beam Injector (NNBI) verification prototype of the China Fusion Engineering Test Reactor (CFETR) employs a built-in ultra-high-speed cryo-adsorption pump utilizing forced-flow cooling as the main pump, which functions through four major processes: cooling, stable operation, regeneration, and temperature rise. The research analyzes the key technical problems of engineering that must be solved,such as natural regeneration takes a longer time with temperature uncontrollable, lead to low experiment efficiency. An efficient and safe controllable technical method for the regeneration heating process was proposed,and regeneration heating experimental control system, including an equipment layer, control layer, data acquisition and monitoring layer, was designed to control the regeneration heating process of the cryo-adsorption pump. The signals collected by temperature sensors are processed and transmitted through signal isolators to the host computer for display and storage.The target temperature is manually set on the host computer. An improved generalized predictive control (GPC) algorithm and a fuzzy proportional integral derivative (PID) control algorithm are used in the control layer to control the heating process.The designed activation regeneration heating control experimental system was embedded in the comprehensive experimental test bench of cryo-adsorption pump for experimental verification, and the test experiment was carried out.The results show that the system can control the regenerative heating process in an efficient, safe and stable way. This lays the foundation for further development of control functions in the regeneration process of the cryo-adsorption pump equipped in the NNBI verification prototype, and provides a design basis for the vacuum system of fusion engineering experimental reactors.

Endüstriyel Sıvı Seviye Denetim Sisteminin Yapay Sinir Ağları ile Modellenmesi

System modeling is a scientific method that combines theory with experimental studies and has an important place in research activities. With the system model, the data to be obtained through real tests and experiments are provided more economically in terms of cost and the critical points of the system are provided with time savings. Some system models are very difficult to obtain using only analytical equations and methods. At this point, artificial neural networks are an alternative way to model complex, uncertain, nonlinear systems. Artificial neural network is an artificial intelligence system that takes the human brain as an example, learns from existing examples, can produce results with noisy, incomplete, non-linear data, and can make predictions and generalizations with high speed and accuracy after learning once. In this study, RT 512 liquid level control system produced by GUNT Hamburg, an experimental process control system for educational purposes, was modeled with an artificial neural network. In order to create the dynamic model, an input-output data set was created by operating the system in open-loop mode. In this set, the level change seen in the liquid level tube against the given control sign has been taken into account. For this process, a certain number of output data was obtained for a certain number of input data by using computer, Arduino, MCP4725 DAC, current/voltage, voltage/current converters. In the developed ANN model, the relationship between the regression curves and the model output and the test data taken from the system was observed and high accuracy was obtained.

Design and Simulation Experiment of Rigid-Flexible Soft Humanoid Finger

This paper is based on the “Fast Pneumatic Mesh Driver” (FPN) used to couple a silicone rubber soft body with a rigid skeleton. A rigid-flexible coupling soft-body human-like finger design scheme is proposed to solve the problem of low load on the soft-body gripping hand. The second-order Yeoh model is used to establish the statics model of the soft humanoid finger, and the ABAQUS simulation analysis software is used for correction and comparison to verify the feasibility of the soft humanoid finger bending. The thickness of the driver cavity and the confining strain layer were determined by finite element simulation. The mold casting process is used to complete the preparation of human-like fingers and design a pneumatic control system for experiments combined with 3D printing technology. The experimental results show that the proposed rigid-flexible coupling soft body imitating the human finger structure can realize the corresponding actions, such as the multi-joint bending and side swinging, of human fingers. Compared with the traditional pure soft-body finger, the fingertip output force is significantly improved. The optimal design and simulation analysis of the human gripper and the feasibility of the application have practical guiding significance.

Archiving System for EAST PF Power Supply

The poloidal field (PF) power supply is an important subsystem of the Experimental Advanced Superconducting Tokamak (EAST). The monitor system of the PF power supply is based on the Experimental Physics and Industrial Control System (EPICS), using Control System Studio (CSS) as the human-machine interface. Archive, which is for data archiving, is a plugin of CSS. This paper creates an archiving system, including archive engine, client, and relational database (RDB). The process variables that need to be archived are configured so that they can be stored to RDB when changed. Real-time archiving for all input signals is realized, and history data can be browsed at any time through CSS. The archiving system provides a data basis for analyzing the EAST PF power supply, applied to the EAST experiment for more than 5 years, showing stable performance.

The Design and Implementation of the Remote Control and Visualization System for Pulse Application Experiments

In order to meet the needs of pulse experiments in different environments, a remote control and visualization system (RCVS) is designed and implemented based on the conceptual design of COntrol, Data Access and Communication (CODAC). RCVS works on the web server and adopts the website deployment mode of LAMP (Linux + Apache + MySQL + PHP/Python) and the working mode of B/S architecture. It includes a remote data acquisition module, a remote real-time visualization module, a monitoring module, and a remote data access module. In the first one, to avoid system deadlock and other problems caused by concurrent operations between local and remote users and concurrent scheduling conflicts between remote users, we have improved the previous solution and adopted the Deterministic Finite Automaton (DFA) and the Two-Phase Locking (2PL) protocol to unify the state of RCVS and that of the overall system and to ensure the serializability of concurrent operations. With regard to real-time data visualization, RCVS adopts the technology of server push to obtain the needed data to minimize the pressure on the server and shun some problems such as server paralysis caused by network congestion in the case of large-scale concurrent request. In addition, RCVS provides a monitoring method based on a heartbeat mechanism and an Application Programming Interface (API) of the web end of the MDSplus database for system status monitoring and remote data retrieval and analysis. Moreover, thanks to the responsive design and the deployment model of B/S architecture, the system can be accessed on any terminal device. This system as part of the overall experimental system will be integrated into the Experimental Advanced Superconducting Tokamak (EAST) neutral beam injection master control system in the future and provide services of remote control and visualization for its long-pulse experiments.

Mu2e DAQ and slow control systems

The Mu2e experiment at the Fermilab Muon Campus will search for the coherent neutrinoless conversion of a muon into an electron in the field of an aluminum nucleus with a sensitivity improvement by a factor of 10,000 over existing limits. The Mu2e Trigger and Data Acquisition System (TDAQ) uses otsdaq as the online Data Acquisition System (DAQ) solution. Developed at Fermilab, otsdaq integrates both the artdaq DAQ and the art analysis frameworks for event transfer, filtering, and processing. otsdaq is an online DAQ software suite with a focus on flexibility and scalability and provides a multiuser, web-based, interface accessible through a web browser. The data stream from the detector subsystems is read by a software filter algorithm that selects events which are combined with the data flux coming from a Cosmic Ray Veto System. The Detector Control System (DCS) has been developed using the Experimental Physics and Industrial Control System (EPICS) open source platform for monitoring, controlling, alarming, and archiving. The DCS System has been integrated into otsdaq. A prototype of the TDAQ and the DCS systems has been built at Fermilab’s Feynman Computing Center. In this paper, we report on the progress of the integration of this prototype in the online otsdaq software.

A novel bearingless interior permanent magnet slice motor for pump*

A 2 pole bearingless interior permanent magnet (IPM) motor with slice rotor configuration is presented in this paper. A novel IPM rotor is designed considering various specifications such as force constant, torque constant and cogging torque. Cogging torque and resulting vibrations affects the motor and levitation operation significantly. Since the cogging torque is a result of the motor geometry, finite element (FE) simulation is used to simulate various rotor geometries to find the desired rotor configuration. FE simulations are also used to obtain other parameters like force and torque constant, and magnetic stiffness for designing control. The final design is fabricated and tested for closed loop levitation control and speed control. The simulation results and experimental control system performance is shown and explained in the paper.

Policy Iteration Reinforcement Learning-based control using a Grey Wolf Optimizer algorithm

This paper presents a new Reinforcement Learning (RL)-based control approach that uses the Policy Iteration (PI) and a metaheuristic Grey Wolf Optimizer (GWO) algorithm to train the Neural Networks (NNs). Due to an efficient tradeoff to exploration and exploitation, the GWO algorithm shows good results in NN training and solving complex optimization problems. The proposed approach is compared to the classical PI RL-based control approach using the Gradient Descent (GD) algorithm, and with the RL-based control approach which uses the metaheuristic Particle Swarm Optimization (PSO) algorithm. The experiments are conducted using a nonlinear servo system laboratory equipment. Each approach evaluated on how well it solves the optimal reference tracking control for an experimental servo system position control system. The policy NNs specific to all three approaches are implemented as state feedback with integrator controllers to remove the steady-state control errors and thus ensure the convergence of the objective function. Because of the random nature of metaheuristic algorithms, the experiments for GWO and PSO algorithms are run multiple times and the results are averaged before the conclusions are presented. The experimental results shows that for the control objective considered in this paper, the GWO algorithm represents a better solution compared to GD and PSO algorithms.

МЕТОДОЛОГИЧЕСКИЕ ОСНОВЫ ДИАГНОСТИКИ ТЕХНОЛОГИЧЕСКИХ СИСТЕМ МЕТАЛЛООБРАБОТКИ ПО ПАРАМЕТРИЧЕСКОЙ НАДЕЖНОСТИ ОБЕСПЕЧЕНИЯ ЗАДАННОГО КАЧЕСТВА ОБРАБАТЫВАЕМЫХ ПОВЕРХНОСТЕЙ

The paper presents the results of research justifying the need for diagnostics of metalworking technological systems on the reliability of ensuring the quality parameters of the surfaces of machine parts during machining. The fundamentals of the methodology of its implementation have been developed. Theoretical models of forming the quality parameters of parts surfaces during machining are considered and refined. This characterizes the scientific novelty of the results obtained. Circuitries for the construction of experimental control systems when conducting bench tests of machined surfaces of parts in conditions close to operational are of practical value. Circuitries are developed and computerized systems based on them for measuring the quality parameters of machined parts surfaces, including the working area of the technological system, are implemented. Recommendations on the rational choice of technological systems and the use of simulation methods in the study of parametric reliability of technological systems are presented. Mathematical and software analysis and processing of experimental results are developed and tested. These results will serve as a foundation for further development of research in the field of parametric reliability of technological systems, improving the quality of domestic engineering products and increasing their competitiveness at the world market.

Progress in Data Transmission and Storage for Long Pulse Data Acquisition System

Since the study in the field of fusion has gradually developed toward the long-pulse experiment mode, long-pulse data has gradually become one of the main data types for pulsed experiments in the field of fusion. For long-pulse data, which is a kind of pulse-type data, it will be more difficult to transmit and store than short-pulse data because of its significant characteristics. In addition, in the design of data acquisition and control system (DACS) in fusion field, Experimental Physics and Industrial Control System (EPICS) has now gradually become the main framework of experimental control system to meet the diversity of devices and complexity of subsystems in large experimental system. However, due to the limitation of EPICS, its effectiveness in handling data transmission and storage under high speed data acquisition is not satisfactory. To solve the data transmission and storage under high-speed sampling, this paper proposes a data transmission and storage solution based on TCP/IP protocol and MDSplus database, which is designed with the concept of segmentation, i.e., data generated from experiments longer than 100 seconds are uploaded and stored in a segmented form. Currently, this system has been tested and applied, and the test result shows that the solution is feasible and the overall test system operates stably and reliably.

Modeling and design of an re-configurable isolated remote for plasma experiments with hard-real-time synchronization

The purpose of this paper is to present the design and implementation of a reconfigurable remote control for performing plasma experiments with Hard-Real-Time (HRT) synchronization under jitter less than 1 microsecond. An additional requirement for a multichannel synchronization system is the use of high-speed optical converters to provide galvanic isolation between powerful modules of the setup and remote control in order to exclude any possibility of disruption of the physical experiment control system. Modeling and development of the software part of the maser remote control panel was performed in the LabVIEW application development environment with Real Time and FPGA modules. The hardware part of the control panel is implemented on a real-time controller working in conjunction with the Xilinx FPGA module. To ensure the optical isolation of synchronization signals, boards of electron-optical converters based on LED lasers with fiber-optic terminals were developed and manufactured. The control program is implemented in a two-module architecture with a HOST application and an FPGA application that exchange data over a 1000BASE-T Ethernet network.

Experiment Control and Monitoring System for LOG-a-TEC Testbed.

The LOG-a-TEC testbed is a combined outdoor and indoor heterogeneous wireless testbed for experimentation with sensor networks and machine-type communications, which is included within the Fed4FIRE+ federation. It supports continuous deployment principles; however, it is missing an option to monitor and control the experiment in real-time, which is required for experiment execution under comparable conditions. The paper describes the implementation of the experiment control and monitoring system (EC and MS) as the upgrade of the LOG-a-TEC testbed. EC and MS is implemented within existing infrastructure management and built systems as a new service. The EC and MS is accessible as a new tab in sensor management system portal. It supports several commands, including start, stop and restart application, exit the experiment, flash or reset the target device, and displays the real-time status of the experiment application. When nodes apply Contiki-NG as their operating system, the Contiki-NG shell tool is accessible with the help of the newly developed tool, giving further experiment execution control capabilities to the user. By using the ZeroMQ concurrency framework as a message exchange system, information can be asynchronously sent to one or many devices at the same time, providing a real-time data exchange mechanism. The proposed upgrade does not disrupt any continuous deployment functionality and enables remote control and monitoring of the experiment. To evaluate the EC and MS functionality, two experiments were conducted: the first demonstrated the Bluetooth Low Energy (BLE) localization, while the second analysed interference avoidance in the 6TiSCH (IPv6 over the TSCH mode of IEEE 802.15.4e) wireless technology for the industrial Internet of Things (IIoT).

Design, simulation, and experiment research on fast control system of steam turbine inlet valve

In this paper, a new fast control system of steam turbine inlet valve is designed, which is composed of the fast closing system and the fast opening system. For the first time, this paper proposes that the fast closing system is designed by means of the special structure of the slide valve in an oil servo motor on the basis of the transformation of the hydraulic control system of steam turbine inlet valve. For the first time, a differential oil discharge fast opening system is designed by use of two cartridge valves. The mathematical model of electro-hydraulic fast control system is presented. With the use of simulation software Advanced Modeling Environment for Simulation of engineering systems , the curves of parameters such as piston displacement, piston velocity, oil pressure of upper and nether cavities of oil servo motor, and flow flux of upper and nether cavities of oil servo motor are obtained. The fast closing time of the piston for whole journey from the simulation results is 0.36 s. The fast opening time of the piston for whole journey from the simulation results is 1.55 s. According to the designed structure of the fast control system, the fast control experiment system is built. The fast closing time of the piston for whole journey from the experiment results is 0.22 s. The fast opening time of the piston for the whole journey from the experiment results is 1.97 s. The simulation and experimental results show that the designed fast control system can realize the fast closing and fast opening of the inlet valve. The fast closing time of the fast control system is <0.5 s, and the fast opening time of the fast control system is <3 s, which meets the fast control time requirement of the steam turbine inlet valve. Compared with the existing fast control system products, the fast control system and the inlet valve servo regulation system share a set of oil sources. And the fast control system has the advantages of low cost, simple structure, easy implementation, etc.

Research and Development of Computer Control Technology Experiment System Based on Network

The state has sufficient funds to invest in education. However, schools in some remote areas still do not have enough funds to set up offline teaching laboratories. In addition, the lack of experimental resources in the school also led to the failure of some teaching courses [1]. Many schools spend a lot of effort to build computer-based control laboratories. Even many schools have developed control technology test-bed in order to save cost. However, due to the large volume of the test bed, its handling is very inconvenient. In order to solve the above problems, experts propose to establish an electronic laboratory in the network. In order to help the experimental courses of mechanical and electrical majors in some schools go smoothly, the research and development of the experimental system of computer control technology based on network has been in progress. This paper briefly introduces the design scheme of network control experiment system and the operation platform of software. In the end, the problems that should be paid attention to in the operation of the system are also put forward.

Inspection and control system for experiments in space robotics

The communication subsystem is one among the various subsystems of a telerobotic space system. It is responsible for coordinating the commands received from the teleoperator control subsystem to the robotic arm, for reading signals from the sensors, and for stating the communication of the telerobot with the ground station. The telerobotic experiment under development by the ITA space robotics research group was developed with the purpose of investigating a robotic space system dynamics and control, including the study of the working and integration of all subsystems involved in the teleoperation control. The lab experiment consists of two identical units of robot manipulators, each of them mounted on its own floating air-supported platform. The objective is to simulate computationally the operations of rendezvous and capture in the microgravity' orbital environment, emulated by the floating manipulators' dynamics. The closed circuit for this system involves the in time position detection, transmission and data processing by using a position-tracking (X, Y, and Z) computer system combined with a Kinect sensor (RGB-D). The computer system comprises two computers capable of processing the positional images with greater accuracy. One of them receive and send the sensor data to a second computer which performs the data processing by proper algorithms in Matlab® and Simulink and sends commands to the robotic arm via WIFI (UDP protocol) network. The robot receives and executes the control signals moving the robotic arms whose position is again detected by the kinect sensor and informed back to the computer system, closing the control mesh and allowing the safe capture of the target. This work deals with the communication subsystem of the space robot experiment and its ability to set an integrated and efficient communication satisfying the telerobot control requirements

Closed-loop identification for a class of nonlinearly parameterized discrete-time systems

This paper studies the identification of discrete-time nonlinear parameterized control systems in given experiments. A necessary and sufficient condition of the closed-loop identifiability is established for the stable experiments and an algorithm is proposed to estimate the parameter. The estimates are shown to be strongly consistent with the convergence rate explicitly computed under some simple algebraic condition.

A novel variable step size least mean square method for adaptive micro-vibration control

The variable step size least mean square algorithm has been suggested since a number of years as a potential solution for improving the performance of least mean square algorithm. In this article, the variable step size least mean square algorithm is classified by the techniques which are used to update step size. Unfortunately, for variable step size least mean square algorithms with forgetting factor, a constant forgetting factor may slow down its convergence speed. For this reason, a variable forgetting factor method for variable step size least mean square is proposed in this article. First, the convergence analysis of a new variable step size least mean square algorithm with the variable forgetting factor is provided. Then, simulations expose the characteristics of this variable forgetting factor method. Last, a micro-vibration control experimental system is established. Four typical variable step size least mean square algorithms and their variable forgetting factor modified version are verified through experiments. The results show that the proposed variable forgetting factor method can effectively improve convergence speed while maintaining the steady-state performance of the variable step size least mean square algorithm with the constant forgetting factor.

Safe and Reusable Approach for Pin-to-Port Assignment in Multiboard FPGA Data Acquisition and Control Designs

This article introduces a robust approach for pin-to-port assignment in multiboard field-programmable gate array designs. The problem has been known for a long time and is especially annoying in relatively large data acquisition (DAQ) systems, such as DAQ and control systems for high-energy physics experiments, where hundreds of differential signals are routed via multiple boards. However, there is still no generic user-friendly open-source solution. The proposed approach has two main goals: safety (check as many potential human mistakes as possible) and reusability (reuse connections mappings, defined in files, in multiple designs). The proposed file format description is concise and comprehensible. It is fully declarative, vendor-agnostic, part-agnostic, and programming language-agnostic from the user's perspective. The article also presents the realization of the idea implemented in the Python language and provides real-life example from the DAQ readout chain for the silicon tracking system for the compressed baryonic matter experiment.

A scalable and reconfigurable industrial-grade Slow Control System for SABRE-South Dark matter experiment

The Sodium iodide Active Background Rejection Experiment-South (SABRE-South) is a direct dark matter detector soon to be deployed in the Stawell gold mine, in Victoria, Australia. Monitoring of external environmental and experimental conditions, (temperature, barometric pressure, relative humidity, high voltage, and seismic vibration) is vital to ensure the data quality of the SABRE search for dark matter via direct detection. These parameters are generally non-time-critical in the range of Hz to a few kHz and constitute a slow control system. We present the design of a novel compact, industrial-grade, and self-contained slow control system for SABRE-South. This system, featuring innovative hardware and software architecture based on National instruments compact RIO (NI-cRIO) and LabVIEW can be scaled up at low-cost and is capable of implementing the functionalities available in high-end SCADA systems while maintaining the flexibility to integrate custom software code (i.e. C++, PYTHON) for bespoke interfacing needs.