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Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To address the issues of low bandwidth, weak real-time performance, and poor synchronization in traditional fieldbuses for multi-axis motion control, a solution for the implementation of an EtherCAT master based on the IgH EtherCAT Master open-source software framework and an embedded hardware platform is proposed. On a hardware platform centered around the AM64x Sitara processor, a Linux real-time operating system based on the Xenomai real-time kernel is constructed, and the IgH master framework is ported to realize a high-performance EtherCAT master. The configuration process of the EtherCAT bus is detailed, a master application program is developed, and methods for the real-time performance optimization of the master—such as exclusive CPU usage by the master process and the optimization of the network card driver—are proposed. Finally, experiments are conducted on a six-axis servo control platform, with the packet analysis of the periodic EtherCAT data frames sent by the master. The experimental results show that the optimized master, under a high-speed communication cycle of 500 microseconds, maintains maximum jitter within 20 microseconds and average jitter within 1 microsecond, meeting the requirements for high-precision multi-axis motion control. [ABSTRACT FROM AUTHOR]

This paper presents a modular hardware control system tailored for industrial applications. The system presented is designed with electrical protection, guaranteeing the reliable operation of its modules in the presence of various field noises and external disturbances. The modular architecture comprises a principal module (mP) and dedicated expansion modules (mEXs). The principal module serves as the network administrator and facilitates interaction with production and control processes. The mEXs are equipped with sensors, conditioning circuits, analog-to-digital converters, and digital signal processing capabilities. The mEX's primary function is to acquire local processing field signals and ensure their reliable transmission to the mP. Two specific mEXs were developed for industrial environments: an electrical signal expansion module (mSE) and the vibration signals expansion module (mSV). The EtherCAT protocol serves as a means of communication between the modules, fostering deterministic and real-time interactions while also simplifying the integration and replacement of modules within the modular architecture. The proposed system incorporates local and distributed processing in which data acquisition, processing, and data analysis are carried out closer to where data are generated. Locally processing the acquired data close to the production in the mEX increases the mP availability and network reliability. For the local processing, feature extraction algorithms were developed on the mEX based on a Fast Fourier Transform (FFT) algorithm and a curve-fitting algorithm that accurately represents a given FFT curve by significantly reducing the amount of data that needs to be transmitted over the mP. The proposed system offers a promising solution to use computational intelligence methodologies and meet the growing need for a modular industrial control system with reliable local data processing to reach a smart industry. The case study of acquiring and processing vibration signals from a real cement ball mill showed a good capacity for processing data and reducing the amount of data. [ABSTRACT FROM AUTHOR]

Copyright of Cyber Security & Data Governance is the property of Editorial Office of Information Technology & Network Security and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recent advances in industrial, railway, and in-vehicle communications demand network architectures that ensure low latency, high synchronization, and efficient bandwidth utilization. While Ethernet for Control Automation Technology (EtherCAT) effectively handles real-time cyclic traffic, managing non-real-time acyclic traffic, such as Ethernet/IP frames, remains challenging. Existing Ethernet-over-EtherCAT (EoE) schemes struggle to balance these traffic types, resulting in inefficient bandwidth use and increased latency under high network loads. To overcome these challenges, we propose an adaptive grouping mechanism for acyclic secondary devices, coupled with a dynamic telegram assignment method, to optimize bandwidth utilization and reduce delay for acyclic traffic without compromising the performance of the cyclic secondary devices traffic. Extensive simulations demonstrate that our approach reduces packet delay and increases bandwidth utilization, even in networks with a large number of acyclic secondary devices. Specifically, the simulation results reveal that our approach achieves up to a 99% reduction in the mean packet delay and significantly enhances bandwidth utilization, making it suitable for complex industrial applications where high performance and scalability are essential. This work offers a practical solution for advancing EtherCAT’s capability to support diverse traffic types in demanding communication environments.

RISC-V offers a modular technical approach combined with an open, royalty-free instruction set architecture (ISA). However, despite its advantages as a fundamental building block for many embedded systems, the escalating complexity and functional demands of real-time applications have made adhering to response time deadlines challenging. For real-time applications of RISC-V, real-time performance analysis is required for various ISAs. In this paper, we analyze the real-time performance of RISC-V through two real-time approaches based on processor architectures. For real-time operating system (RTOS) applications, we adopted FreeRTOS and evaluated its performance on HiFive1 Rev B (RISC-V) and STM3240G-EVAL (ARM M). For real-time Linux, we utilized Linux with the Preempt-RT patch and tested its performance on VisionFive 2 (RISC-V), MIO5272 (x86-64), and Raspberry Pi 4 B (ARM A). Through these experiments, we examined the response times on the real-time mechanisms of each operating system. Additionally, in the Preempt-RT experiments, scheduling latencies were evaluated by means of the cyclictest. These are very important parameters for implementing real-time applications comprised of multi-tasking. Finally, in order to show the real-time capabilities of RISC-V practically, we implemented motion control of a six-axis collaborative robot, which was performed on the VisionFive 2. This implementation provided a comparative result of RISC-V's performance against the x86-64 architecture. Ultimately, the results indicated that the real-time performance of RISC-V for real-time applications was feasible. A noticeable achievement of this research is its first implementation of an EtherCAT master on RISC-V designed for real-time applications. The successful implementation of the EtherCAT master on RISC-V shows real-time capabilities for a wide range of real-time applications. [ABSTRACT FROM AUTHOR]

A personal-computer-based and a Raspberry Pi single-board computer-based virtual force sensor with EtherCAT communication for a six-axis robotic arm are proposed in this paper. Both traditional mathematical modeling and machine learning techniques are used in the establishment of the dynamic model of the robotic arm. Thanks to the high updating rate of EtherCAT, the machine learning-based dynamic model on a personal computer achieved an average correlation coefficient between the estimated torque and the actual torque feedback from the motor driver of about 0.99. The dynamic model created using traditional mathematical modeling and the Raspberry Pi single-board computer demonstrates an approximate correlation coefficient of 0.988 between the estimated torque and the actual torque. The external torque observer is established by calculating the difference between the actual torque and the estimated torque, and the virtual force sensor converts the externally applied torques calculated for each axis to the end effector of the robotic arm. When detecting external forces applied to the end effector, the virtual force sensor demonstrates a correlation coefficient of 0.75 and a Root Mean Square Error of 12.93 N, proving its fundamental competence for force measurement. In this paper, both the external torque observer and the virtual force control are applied to applications related to sensing external forces of the robotic arm. The external torque observer is utilized in the safety collision detection mechanism. Based on experimental results, the system can halt the motion of the robotic arm using the minimum external force that the human body can endure, thereby ensuring the operator's safety. The virtual force control is utilized to implement a position and force hybrid controller. The experimental results demonstrate that, under identical control conditions, the position and force hybrid controller established by the Raspberry Pi single-board computer achieves superior control outcomes in a constant force control scenario with a pressure of 40 N. The average absolute error is 9.62 N, and the root mean square error is 11.16 N when compared to the target pressure. From the analysis of the results, it can be concluded that the Raspberry Pi system implemented in this paper can achieve a higher control command update rate compared to personal computers. As a result, it can provide greater control benefits in position and force hybrid control. [ABSTRACT FROM AUTHOR]

With the continual technical advancement, the requirements for the performance of the EtherCAT master station are raised in high-end applications. The EtherCAT master station configured with traditional software runs Windows or Linux operating system, completely depending on the real-time capability of the operating system regarding performance and stability, and suffering from jitter generally at the microsecond level, so it can hardly meet the requirements in high-end applications. In addition, the clock of the first slave station is used as the system clock for the traditional clock synchronization algorithm, imposing certain limitations. Therefore, this paper first elaborates the current status of the EtherCAT master station research, and then proposes an FPGA-based hardware EtherCAT master station scheme and a DC synchronization algorithm based on the FPGA master clock, followed by the description on the implementation method of the hardware EtherCAT master station; the final part contains the experimental verification on the proposed master station system with six general-purpose servo drives as the slave devices. Base on the verification results, with only 5 ns data frame jitter in the master station communication of the current design and with the clock synchronization algorithm described herein, SYNC0 interrupts are synchronized in real time among slaves, which can meet the requirements of various high-end application scenario; moreover this master station can be flexibly applied to different hardware platforms due to the portability of FPGA codes, which has a strong engineering guiding significance.

Because of its simplicity and the support of numerous useful libraries, Python has become one of the most popular programming languages for application development, even in embedded systems. However, in existing control systems where specific tasks must meet specific temporal deadlines and support schedulability with proper priority assignments, the Python interpreter may not satisfy real-time requirements, owing to features such as the global interpreter lock and garbage collector. This paper addresses these constraints with an approach that executes periodic real-time tasks under the fixed-priority preemptible scheduler of RT-Preempt. First, we implemented a Python real-time module that allows users to create and execute periodic tasks with fixed priorities based on Python. Then, we conducted experiments on an open embedded system, in this case, a Raspberry Pi 4. We evaluated the real-time performance, focusing on test metrics for control systems, such as task periodicity, responsiveness, and interrupt response. The results were then compared to those of conventional real-time tasks developed using the C language to validate the feasibility of the proposed method. Finally, we performed experimental validation by tracking the position of EtherCAT servo motors to demonstrate the feasibility of a Python-based real-time control system in a practical application. [ABSTRACT FROM AUTHOR]

A personal-computer-based and a Raspberry Pi single-board computer-based virtual force sensor with EtherCAT communication for a six-axis robotic arm are proposed in this paper. Both traditional mathematical modeling and machine learning techniques are used in the establishment of the dynamic model of the robotic arm. Thanks to the high updating rate of EtherCAT, the machine learning-based dynamic model on a personal computer achieved an average correlation coefficient between the estimated torque and the actual torque feedback from the motor driver of about 0.99. The dynamic model created using traditional mathematical modeling and the Raspberry Pi single-board computer demonstrates an approximate correlation coefficient of 0.988 between the estimated torque and the actual torque. The external torque observer is established by calculating the difference between the actual torque and the estimated torque, and the virtual force sensor converts the externally applied torques calculated for each axis to the end effector of the robotic arm. When detecting external forces applied to the end effector, the virtual force sensor demonstrates a correlation coefficient of 0.75 and a Root Mean Square Error of 12.93 N, proving its fundamental competence for force measurement. In this paper, both the external torque observer and the virtual force control are applied to applications related to sensing external forces of the robotic arm. The external torque observer is utilized in the safety collision detection mechanism. Based on experimental results, the system can halt the motion of the robotic arm using the minimum external force that the human body can endure, thereby ensuring the operator’s safety. The virtual force control is utilized to implement a position and force hybrid controller. The experimental results demonstrate that, under identical control conditions, the position and force hybrid controller established by the Raspberry Pi single-board computer achieves superior control outcomes in a constant force control scenario with a pressure of 40 N. The average absolute error is 9.62 N, and the root mean square error is 11.16 N when compared to the target pressure. From the analysis of the results, it can be concluded that the Raspberry Pi system implemented in this paper can achieve a higher control command update rate compared to personal computers. As a result, it can provide greater control benefits in position and force hybrid control.

Abstract Background Many patients with neurological movement disorders fear to fall while performing postural transitions without assistance, which prevents them from participating in daily life. To overcome this limitation, multi-directional Body Weight Support (BWS) systems have been developed allowing them to perform training in a safe environment. In addition to overground walking, these innovative/novel systems can assist patients to train many more gait-related tasks needed for daily life under very realistic conditions. The necessary assistance during the users’ movements can be provided via task-dependent support designs. One remaining challenge is the manual switching between task-dependent supports. It is error-prone, cumbersome, distracts therapists and patients, and interrupts the training workflow. Hence, we propose a real-time motion onset recognition model that performs automatic support switching between standing-up and sitting-down transitions and other gait-related tasks (8 classes in total). Methods To predict the onsets of the gait-related tasks, three Inertial Measurement Units (IMUs) were attached to the sternum and middle of outer thighs of 19 controls without neurological movement disorders and two individuals with incomplete Spinal Cord Injury (iSCI). The data of IMUs obtained from different gait tasks was sent synchronously to a real-time data acquisition system through a custom-made Bluetooth-EtherCAT gateway. In the first step, data was applied offline for training five different classifiers. The best classifier was chosen based on F1-score results of a Leave-One-Participant-Out Cross-Validation (LOPOCV), which is an unbiased way of testing. In a final step, the chosen classifier was tested in real time with an additional control participant to demonstrate feasibility for real-time classification. Results Testing five different classifiers, the best performance was obtained in a single-layer neural network with 25 neurons. The F1-score of $$86.83\% \pm 6.2\%$$ 86.83 % ± 6.2 % and $$92.01\%$$ 92.01 % are achieved on testing using LOPOCV and test data ( $$30\%$$ 30 % , participants = 20), respectively. Furthermore, the results from the implemented real-time classifier were compared with the offline classifier and revealed nearly identical performance (difference = $$0.08 \%$$ 0.08 % ). Conclusions A neural network classifier was trained for identifying the onset of gait-related tasks in real time. Test data showed convincing performance for offline and real-time classification. This demonstrates the feasibility and potential for implementing real-time onset recognition in rehabilitation devices in future.

This paper presents a 13.2 kV class 3-phase solid-state transformer (SST) based on EtherCAT communication. In general, when the structure of the unit module is determined, the number of high-frequency isolated transformers (HFIT) is also proportional to the number of modules. The structure most considered in SST is a 1:1 combination of AC/DC converter and DC/DC converter. To optimally implement a 3-phase SST, a topology for reducing passive elements such as switching elements and HFIT is proposed. It also describes the design of HFIT used in DC/DC converter. EtherCAT communication with high transmission speed and expandability is applied to control the SST composed of unit modules stably, and a multi-core microcontroller unit (MCU) is applied to achieve both a high-speed communication cycle and complicated control algorithm execution. The discussions are validated using a 300 kW 13.2 kV class 3-phase SST prototype in various conditions. [ABSTRACT FROM AUTHOR]

As part of the development process, scaled testing of wave energy converter devices are necessary to prove a concept, study hydrodynamics, and validate control system approaches. Creating a low-cost, small, lightweight data acquisition system suitable for scaled testing is often a barrier for wave energy converter developers’ ability to test such devices. This paper outlines an open-source solution to these issues, which can be customized based on specific needs. This will help developers with limited resources along a path toward commercialization.

The increasing demand for rapid application development tools, especially those employing high-level languages such as Python, has underscored the importance of utilizing a wide array of popular libraries while addressing real-time constraints in distributed hardware systems. This paper introduces PyIgH, a unified architecture of an IgH EtherCAT master based on Python, specifically designed to satisfy hard real-time requirements in an EtherCAT network. Implemented as a Python module, PyIgH exposes the functionalities and capabilities of an open-source EtherCAT master, facilitating seamless configuration and control of EtherCAT slave devices within the Python runtime environment. Real-time adaptation of the POSIX library, encapsulated within Python, is also utilized to satisfy the timing requirements of EtherCAT. The feasibility of the proposed approach is verified by analyzing the real-time performance in terms of periodicity and in-controller delay of the EtherCAT control task with a 1 kHz cycle. Experimental results demonstrate that PyIgH is suitable for hard real-time applications and serves as a valid alternative to conventional low-level EtherCAT masters. Additionally, a practical application involving motion control of a six-axis collaborative robot showcases consistent performance of PyIgH within a real-time multi-tasking environment. • A Python-based EtherCAT master for distributed hard real-time control systems. • Configuration and control of EtherCAT devices within the Python runtime environment. • Comprehensive performance analysis compared with conventional and existing solutions. • Practical experiments on a 6-axis collaborative robot motion control for validation. • Potential to integrate AI models with real-time tasks and control EtherCAT devices. [ABSTRACT FROM AUTHOR]

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Many patients with neurological movement disorders fear to fall while performing postural transitions without assistance, which prevents them from participating in daily life. To overcome this limitation, multi-directional Body Weight Support (BWS) systems have been developed allowing them to perform training in a safe environment. In addition to overground walking, these innovative/novel systems can assist patients to train many more gait-related tasks needed for daily life under very realistic conditions. The necessary assistance during the users' movements can be provided via task-dependent support designs. One remaining challenge is the manual switching between task-dependent supports. It is error-prone, cumbersome, distracts therapists and patients, and interrupts the training workflow. Hence, we propose a real-time motion onset recognition model that performs automatic support switching between standing-up and sitting-down transitions and other gait-related tasks (8 classes in total).Methods: To predict the onsets of the gait-related tasks, three Inertial Measurement Units (IMUs) were attached to the sternum and middle of outer thighs of 19 controls without neurological movement disorders and two individuals with incomplete Spinal Cord Injury (iSCI). The data of IMUs obtained from different gait tasks was sent synchronously to a real-time data acquisition system through a custom-made Bluetooth-EtherCAT gateway. In the first step, data was applied offline for training five different classifiers. The best classifier was chosen based on F1-score results of a Leave-One-Participant-Out Cross-Validation (LOPOCV), which is an unbiased way of testing. In a final step, the chosen classifier was tested in real time with an additional control participant to demonstrate feasibility for real-time classification.Results: Testing five different classifiers, the best performance was obtained in a single-layer neural network with 25 neurons. The F1-score of [Formula: see text] and [Formula: see text] are achieved on testing using LOPOCV and test data ([Formula: see text], participants = 20), respectively. Furthermore, the results from the implemented real-time classifier were compared with the offline classifier and revealed nearly identical performance (difference = [Formula: see text]).Conclusions: A neural network classifier was trained for identifying the onset of gait-related tasks in real time. Test data showed convincing performance for offline and real-time classification. This demonstrates the feasibility and potential for implementing real-time onset recognition in rehabilitation devices in future. [ABSTRACT FROM AUTHOR]

While the industrial robotic manipulator is a kind of multi-input and multi-output human-like operation and highly autonomous control system. It is widely used in medical care, home service, industrial manufacturing and other fields. With the integration of cyber-physical system networks and the Internet in recent years, the control commands of the industrial robotic arm control system can be totally exposed to the Internet. Under these circumstances, the chances of successful attacks by attackers to systems are increasing year by year. Compared to the security of traditional cyber physical system, the security of manipulator control system is a very challenging problem. In this paper, a covert attack method of 7 degrees of freedom (7-DOF) manipulator control system was proposed. Firstly, based on the inverse kinematics equation of the manipulator, the motion planning and modeling of 7-DOF manipulator, which communicated by EtherCAT, was carried out. Secondly, according to the research and analysis of particle swarm optimization method, a 7-DOF manipulator system PID parameter identification algorithm based on chaotic theory for multi- swarm particle swarm optimization was proposed. Parameter identification mainly identified the PID parameters of each joint. The principle and derivation process of the algorithm were described in detail. Finally, the experimental platform of manipulator control system was built and the identified parameters were used in combination with the covert attack principle to conduct the experiment. The proposed method was compared with other traditional attack methods, such as state machine attack and traditional sine attack. The results show that the covert attack model of the proposed 7-DOF manipulator can destroy the data integrity and accuracy of the manipulator system, and has a good concealment, which verifies the effectiveness and feasibility of the established attack model. The attack experiment platform constructed in this paper provides the physical basis for the attack and defense experiment of the manipulator, and it has certain reference significance for similar researchers.

In the study, we develop a method to improve the accuracy of master-slave synchronization in EtherCAT networks. The method involves two key compensations that are not considered in the EtherCAT protocol. First, the propagation delay between the master and reference slave is measured, and the system time of the reference slave is then compensated for the measured propagation delay. Second, the bias component of the synchronization error between the master and reference slave is periodically estimated, and system time of each slave is then compensated for the estimated bias component. The entire method is implemented as part of the master application without modifying the EtherCAT protocol or requiring excessive computation load or large memory space. Thus, the developed method is advantageous because it can be immediately applied at low cost to existing EtherCAT networks. By performing extensive experiments based on a Linux-based EtherCAT master, we demonstrate that the developed method significantly improves the accuracy of the master-slave synchronization in EtherCAT networks.

When designing and manufacturing industrial computer systems, many different issues must be considered. The most important of these are the temporal characteristics and real-time operation. Another factor is the distribution of the system, usually over a wide area, operation in harsh environments, and, finally, the system’s dependability. When addressing the last issue, redundancy is commonly employed. This can be applied in many ways, e.g., by providing redundant communication links (buses and communication modules) and redundant sensors, input/output modules. This article considers systems that have computing unit redundancy, for which programmable logic controllers (PLCs) are often used. On the one hand, systems of this kind should be reliable and capable of real-time operations. On the other hand, they should be economically attractive. There are many solutions available on the market for the implementation of systems with redundancy. However, they are always rather expensive. Of course, the price is for a robust solution with dedicated hardware and many built-in features that are crucial in highly reliable systems, such as autodiagnostics. Nevertheless, such powerful products are not always required. This article presents an example of a cost-effective implementation of an industrial controller with hot-standby redundancy using regular devices and an Ethernet communication interface for the needs of synchronization of the computing units. For this purpose, EtherCAT and real-time Ethernet protocols were used. Note to Practitioners—This article is motivated by the problem of high cost of application of systems with computing units redundancy based on dedicated components, such as the latest S7-1500R/H Redundant System by Siemens or PACSystems Profinet System Redundancy by Emerson (former GE IP). The above solutions are powerful and sophisticated. However, sometimes, simpler solutions would suffice. This article shows how a system with computing unit redundancy could be built in a cost-effective way and, at the same time, provide all the basic features expected from systems with redundancy, i.e., fault detection, automatic switchover, and synchronization. All this is done with a common embedded programmable device and an open Ethernet-based communication network. [ABSTRACT FROM AUTHOR]

Despite significant advances in robotic technologies, few affordable robots for domestic applications are commercially available. This study aimed to develop an affordable yet practical mobile manipulator for use in household environments. The proposed mobile manipulator features a software-based real-time controller to control the motion of the manipulator and mobile base. The real-time controller was implemented on a single on-board Windows PC and can control the actuator and IO devices via EtherCAT communication. The major functionalities of the mobile manipulator include the pick-and-place of household objects and autonomous navigation within a domestic environment. For pick-and-place tasks, a deep neural network (DNN) was employed to recognize the object to pick up. For autonomous navigation, open-source ROS packages for SLAM and navigation were used along with the measurements from a LiDAR sensor and odometry. The feasibility of using the developed robot for domestic applications was experimentally evaluated. [ABSTRACT FROM AUTHOR]

Toplam maliyeti azaltarak piyasaya hızlı ve aynı standartta ürün sunmak seri üretim yapan firmaların önemli hedefleri arasındadır. Fakat sadece üretimi değil üretimden satışa kadar olan tüm süreci (geliştirme, üretim, lojistik) hızlı, etkin, esnek ve kontrol edilebilir şekilde yönetmek gerekmektedir. Bu çalışmada, lojistik faaliyetler içerisinde yer alan, ürünlerin depolanması, ürünün müşteriye sevkiyatının yapılması, gelen ürünlerin ürün ve beden temelli ayrıştırılması gibi operasyonlar yapılan bir depolama tesisinde, depolama hattının hızını ve etkinliği arttırmaya yönelik iyileştirme çalışması ele alınmıştır. Depolama tesisi, depolama süreçlerini modüler olarak incelemek için çalışma bölgelerine ayrılmıştır. Yapılan iyileştirme bir çalışma bölgesi içerisindeki beş konveyör hattını kapsamaktadır. Hazırlanmak üzere gelen ilk ürünle, hazırlanmış son ürünün ortak kullandığı bu bölgede, sayıcılara bağlı olarak işleyen denetim yapısı gelen / giden hatların yoğunluk durumlarını temel alan denetleyici ile değiştirilerek iyileştirme sağlanmıştır. Ürün depolama kapasitesinde aynı çalışma koşulları göz önüne alındığında önemli bir artış gözlenmiştir.

Toplam maliyeti azaltarak piyasaya hızlı ve aynı standartta ürün sunmak seri üretim yapan firmaların önemli hedefleri arasındadır. Fakat sadece üretimi değil üretimden satışa kadar olan tüm süreci (geliştirme, üretim, lojistik) hızlı, etkin, esnek ve kontrol edilebilir şekilde yönetmek gerekmektedir. Bu çalışmada, lojistik faaliyetler içerisinde yer alan, ürünlerin depolanması, ürünün müşteriye sevkiyatının yapılması, gelen ürünlerin ürün ve beden temelli ayrıştırılması gibi operasyonlar yapılan bir depolama tesisinde, depolama hattının hızını ve etkinliği arttırmaya yönelik iyileştirme çalışması ele alınmıştır. Depolama tesisi, depolama süreçlerini modüler olarak incelemek için çalışma bölgelerine ayrılmıştır. Yapılan iyileştirme bir çalışma bölgesi içerisindeki beş konveyör hattını kapsamaktadır. Hazırlanmak üzere gelen ilk ürünle, hazırlanmış son ürünün ortak kullandığı bu bölgede, sayıcılara bağlı olarak işleyen denetim yapısı gelen / giden hatların yoğunluk durumlarını temel alan denetleyici ile değiştirilerek iyileştirme sağlanmıştır. Ürün depolama kapasitesinde aynı çalışma koşulları göz önüne alındığında önemli bir artış gözlenmiştir.

In view of the problem that the reliability and maintainability of the coal mine underground monitoring system are reduced when emergency occurs, a redundant network of the coal mine underground monitoring system based on industrial Ethernet EtherCAT communication is proposed in the present study. By studying the composition, working principle and message structure of industrial Ethemet EtherCAT, the characteristics of EtherCAT communication network with or without redundant structure are compared. The link redundancy mechanism is added to the regular EtherCAT master driver. The redundant frame propagation mechanism, fault point location and recovery strategy in network port fault, link fault and node fault are planned, respectively. Under laboratory conditions, a simulation test platform for the underground power monitoring system is established based on the EtherCAT communication net work and the underground coal mine power supply network, and a redundant mechanism is added to test its performance. The results show that the system has superior performance and the reliability of the system is markedly improved. [ABSTRACT FROM AUTHOR]

With the gradual development and competition among enterprises, the products of motion control system are diversified and the performance difference is bigger. The technology of motion control system is monopolized by a few foreign professional manufacturers. The development of motion controller in China is relatively late, and the number with independent research and development ability is still in the minority. Compared with foreign countries, some developed countries still restrict the export of high-end products to China. This paper will use Loongson 3A3000 processor to realize open motion controller. Loongson series processor is a general domestic processor developed by Institute of computing technology, Chinese Academy of Sciences. It uses MIPS instruction system. At present, Loongson is gradually catching up with and surpassing the world advanced level. The communication module of motion controller uses EtherCAT real-time Ethernet, which has the characteristics of high efficiency, flexible topology and short refresh cycle. At present, there are few cases of open motion controller based on domestic CPU Loongson, which provides a typical case for independent innovation in China. [ABSTRACT FROM AUTHOR]

Distributed control is the most popular control strategy for controlling numerous slave devices. However, the performance of slave devices is hard to improve because the control algorithm is handled by the commercial slave devices. Therefore, this paper proposes a hybrid control structure that follows the concept of centralized control strategy and handles part of the control loop on the master computer in a distributed control system through EtherCAT fieldbus. In this study, different advanced control methods such as robust control and learning control were applied to handle the position control loop of a scanning mirror system in a selective laser melting (SLM) system with stringent demand of position error around 40 µm based on EtherCAT fieldbus. By designing a proper controller, the experiment results showed that the tracking performance was significantly improved. The tracking error dropped by about 80% after the proposed hybrid control structure was applied. By applying the proposed hybrid control structure, one can improve the high-performance-requirement devices, while reducing the calculation burden of the master computer for other low-performance-requirement devices by retaining the benefit of distributed control. [ABSTRACT FROM AUTHOR]

In industrial applications, EtherCAT control technology requires the use of TwinCAT control software with dedicated servos for real-time control. In order to solve the limitations of the practical application of EtherCAT, this experiment combines EtherCAT real-time control technology with Simulink Real-Time real-time control technology to design a new EtherCAT real-time control technology based on Simulink Real-Time. In the experiment, D2 delta robot is used as the control object, and the real-time control environment of Simulink Real-Time is set up to build the EtherCAT real-time communication model. The established real-time control model is added to the robot control system to realize the motion control of the robot. [ABSTRACT FROM AUTHOR]

At the beginning of the current century, Ethernet-based communication networks began to be implemented in industrial applications. Some previously used protocols were migrated to Ethernet networks, while many others were strictly developed for this communication medium. Numerous industrial Ethernet protocols do not deliver all the capabilities provided by the Ethernet. For example, limitations may arise associated with wireless communication, use of dedicated switching devices, or operation solely for certain topologies. On the other hand, new technologies are now available, such as software defined networks (SDN), that add new features to Ethernet-based communication systems. In this paper, an EtherCAT network in combination with SDN is analyzed. EtherCAT network may only consist of devices with an implemented EtherCAT protocol stack. Therefore, regular Ethernet switches cannot typically be used in this network and, hence, special network infrastructure may be required to create topologies other than standard line topology. It is shown, however, that this limitation can be overcome by the application of SDN. In addition, a definition of datagram forwarding rules (called SDN flows here) is given, and we demonstrate that EtherCAT datagrams can be sent through routes that are required for proper EtherCAT network operation.

Synchronization between devices (in particular drive systems) is paramount for multi-axis motion control systems used in Computerized Numerical Control (CNC) machines, robots, and specialized technology machines used in many areas of the manufacturing industry. EtherCAT is an Ethernet-based network that is one of the most popular industrial networks for multi-axis motion control systems. EtherCAT is standardized in the IEC 61158 and IEC 61784 standards. In the article, an EtherCAT communication network for electrical drives is presented. The article focuses on the synchronization in the EtherCAT network consisting of one master device and slave servo drive devices. Special attention is given to synchronization mechanisms in EtherCAT, such as distributed clocks in slave servo drives devices. For this purpose, a laboratory stand was built consisting of two prototype servo drive devices with BLDC motors equipped with EtherCAT communication modules. A description of the working developed EtherCAT communication modules is given. Authors in communication modules ware used an EtherCAT Slave Controller (ESC) chip (AX58100) to implement lower EtherCAT layers. EtherCAT application layer was implemented in software form on a 32-bit microcontroller, based on CANopen over EtherCAT (CoE) CAN in Automation 402 (CiA402) profile. This research’s main contribution was to show the time dependencies regarding synchronization in terms of data flow in the EtherCAT communication stack in slave servo drive devices. The research results showed that the synchronous operation of drives is mainly influenced not by the mechanism of distributed clocks that ensures synchronization in the EtherCAT network but the implementation of the highest layer of the communication stack in slave servo drive devices. Experimental results are presented that prove the modules’ adequacy for use in high-performance motion control systems.

The pulse generator is the basic equipment for device drivers and control, widely used in many occasions, such as power electronics, motion control, vehicle control, etc. However, the used pulse generator is weak in communication, which cannot meet high-speed control requirements or be used in the intelligent manufacturing application. To solve the above problem, this paper designed a pulse generator with real-time industrial ethernet EtherCAT and Loongson processor LS1C. The designed pulse generators can form the daisy chain and ring topology by EtherCAT. And the pulse generator is very flexible and suited for many different applications with its four operation modes. Finally, experiment results are presented to demonstrate the operation modes and performance.

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Studia Poliana is the property of Studia Poliana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Smart factory addresses the vertical integration of physical entities and information systems. Network and cloud are two essential infrastructures to achieve this goal. Among them, the network provides interconnection for communication and data flow, while the cloud provides powerful and elastic computing and storage abilities for big data and intelligent applications. This paper presents a cloud-centric framework for the implementation of the smart factory. Based on this framework, three high leveled protocols viz., EtherCAT, DDS, and OPC UA are selected to implement machine network (controller to sensors/actuators communication), machine to machine communication, and machine to cloud communication respectively, to satisfy diverse communication requirements of the smart factory. An integrated architecture for combining ontology knowledge and semantic data to support intelligent applications is also proposed. These network and data process schemes are verified in a smart factory prototype for personalized candy packing application.

This paper presents the potential of combining ROS (Robot Operating System), its state-of-art software, and EtherCAT technologies to design real-time robot control architecture for human–robot collaboration. For this, the advantages of an ROS framework here are it is easy to integrate sensors for recognizing human commands and the well-developed communication protocols for data transfer between nodes. We propose a shared memory mechanism to improve the communication between non-real-time ROS nodes and real-time robot control tasks in motion kernel, which is implemented in the ARM development board with a real-time operating system. The jerk-limited trajectory generation approach is implemented in the motion kernel to obtain a fine interpolation of ROS MoveIt planned robot path to motor. EtherCAT technologies with precise multi-axis synchronization performance are used to exchange real-time I/O data between motion kernel and servo drive system. The experimental results show the proposed architecture using ROS and EtherCAT in hard real-time environment is feasible for robot control application. With the proposed architecture, a user can efficiently send commands to a robot to complete tasks or read information from the robot to make decisions, which is helpful to reach the purpose of human–robot collaboration in the future.

The main global trends in the production of high-technology CNC systems are identified. Topics analyzed include system architecture; the use of high-speed industrial networks based on fieldbus technologies; the potential of multiple-channel and multiple-axis machining; spline interpolation in the machining of complex contours and free surfaces; and five-coordinate machining with 3D correction of the tool radius and length. In the light of global trends, decisions are made regarding the development of the AksiOMA Kontrol CNC system. [ABSTRACT FROM AUTHOR]

Aiming at the application problems of real-time industrial Ethernet EtherCAT in servo motion control, the real-time embedded Linux system, the construction of EtherCAT master and the servo motor control mode were studied. The master software solution combining Linux&Xenomai real-time system and IGH EtherCAT master protocol stack was put forward. The embedded EtherCAT master was built based on the AM4377 hardware platform, the application program of the master was developed, the bus configuration flow was expounded, and the periodic real-time task was realized. The servo motion control system based on EtherCAT was designed and the multi-axis servo motion control was realized. Moreover, the master periodic real-time task performance test and machine tool processing experiments were carried out. The results indicate that the embedded real-time EtherCAT master can accurately perform periodic real-time tasks, and has good real-time performance, which can meet the performance requirements of servo motion control system. [ABSTRACT FROM AUTHOR]

EtherCAT has become one of the leading real-time Ethernet solutions for networked industrial systems, where a reliable communication infrastructure is needed due to highly error-prone environments. However, existing work on EtherCAT mainly focuses on clock synchronization and timeliness improvement. The reliability of EtherCAT-based networked systems has largely been ignored. In this paper, we present a proportional integral derivative (PID)-based feedback control scheme that aims at enhancing reliability of networked systems under timing and system resource constraints. Instead of retransmitting data upon error detection, we use forward error control technique based on inequality of arithmetic and geometric means to achieve the required system reliability at a low deadline miss rate of messages. We further optimize the forward error control technique and design a fast and fair error resilient mechanism by using a cooperative game. In addition to reliability enhancement, our PID-based error control scheme can also improve the stability of a system in terms of deadline miss rate in the presence of burst errors. Simulation results show that the proposed scheme can achieve reliability enhancement of up to 91% compared to benchmarking methods. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low accuracy for forging load, speed, and unstable for beam in finite-stroke forokoked, a scheme for process optimization was proposed based on EtherCAT and genetic-BP network. Master monitoring interface was designed by LabVIEW. Then communication protocol between each module was configured, and ActiveX was used to design interface between genetic-BP and LabVIEW, UDP/IP was used to exchange monitoring data. Simulation precision was used to simulate the optimization accuracy of the nonlinear model, and beam state was monitored in real time. The results indicate that the overall control error of load and speed is less than 2.5% through genetic-BP algorithm optimization, and beam leveling state is stable, which effectively improves the problems of isothermal forging electro-hydraulic servo system. [ABSTRACT FROM AUTHOR]

Toplam maliyeti azaltarak piyasaya hızlı ve aynı standartta ürün sunmak seri üretim yapan firmaların önemli hedefleri arasındadır. Fakat sadece üretimi değil üretimden satışa kadar olan tüm süreci (geliştirme, üretim, lojistik) hızlı, etkin, esnek ve kontrol edilebilir şekilde yönetmek gerekmektedir. Bu çalışmada, lojistik faaliyetler içerisinde yer alan, ürünlerin depolanması, ürünün müşteriye sevkiyatının yapılması, gelen ürünlerin ürün ve beden temelli ayrıştırılması gibi operasyonlar yapılan bir depolama tesisinde, depolama hattının hızını ve etkinliği arttırmaya yönelik iyileştirme çalışması ele alınmıştır. Depolama tesisi, depolama süreçlerini modüler olarak incelemek için çalışma bölgelerine ayrılmıştır. Yapılan iyileştirme bir çalışma bölgesi içerisindeki beş konveyör hattını kapsamaktadır. Hazırlanmak üzere gelen ilk ürünle, hazırlanmış son ürünün ortak kullandığı bu bölgede, sayıcılara bağlı olarak işleyen denetim yapısı gelen / giden hatların yoğunluk durumlarını temel alan denetleyici ile değiştirilerek iyileştirme sağlanmıştır. Ürün depolama kapasitesinde aynı çalışma koşulları göz önüne alındığında önemli bir artış gözlenmiştir. [ABSTRACT FROM AUTHOR]

A new material testing reactor Jules Horowitz Reactor is under construction at CEA Cadarache. The materials to be irradiated will be placed into experimental devices around the reactor. Process and measurements of experimental devices will be carried out by command control. A data acquisition system having processing performances will be associated to the programmable logic controller. The challenge is to design and realize for twenty experiment devices a high availability data acquisition system architecture for 50 years of sustainability. The real time target will achieve 24/7 data acquisition and real time processing. This scalable architecture could be use as well for JHR experimental devices with high availability as for testbed. This architecture could be run on a standalone station for a measuring bench or deployed on cluster for high availability. CAREDAS’s design is modular and use proven widely used open source solutions. All parts are independent from each other and can be replaced with another technology with the same functionalities. This ensures sustainability and control of software sources.

Guaranteeing isochronous transfer of control commands is an essential function for networked motion control systems. The adoption of real-time Ethernet (RTE) technologies may be profitable in guaranteeing deterministic transfer of control messages. However, unpredictable behavior of software in the motion controller often results in unexpectedly large deviation in control message transmission intervals, and thus leads to imprecise motion. This paper presents a simple and efficient heuristic to guarantee the end-to-end isochronous control with very small jitter. The key idea of our approach is to adjust the phase offset of control message transmission time in the motion controller by investigating the behavior of motion control task. In realizing the idea, we performed a pre-runtime analysis to determine a safe and reliable phase offset and applied the phase offset to the runtime code of motion controller by customizing an open-source based integrated development environment (IDE). We also constructed an EtherCAT-based motion control system testbed and performed extensive experiments on the testbed to verify the effectiveness of our approach. The experimental results show that our heuristic is highly effective even for low-end embedded controller implemented in open-source software components under various configurations of control period and the number of motor drives.

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the tension analysis of multi-wire saw synchronization control system, improve tension dancer design, wire passing design, and wire traverse design. To reduce the emergency shock, design a flexible traverse direction switch method. To realize multi-axis synchronization, virtual main axis is used based on analysis of axis coupling relation. To avoid the shake of two main rollers, a master slave control method is designed and the two motors can get accurate torque synchronization. Multi-wire saw is very few used for tile cut before, for processing resistance produces a big error between wire theory position and fact position, so the accuracy is very bad. An intelligent compensation method is designed to improve the tile cut error and correct the error by segment to improve production quality. Tile cut error mechanism is analyzed, tile detection standard is given, error compensation theory is put forward, a compensation table is designed, and compensation solution error is analyzed. At last, the hardware and software structure are explained, control strategy of multi-wire saw is introduced, and sample tile product is shown by DX2240R machine. [ABSTRACT FROM AUTHOR]

In designing a distributed hard real-time system, it is important to reduce the end-to-end delay of each real-time message in order to ensure quick responses to external inputs and a high degree of synchronization among cooperating actuators. In order to provide a real-time guarantee for each message, the related literature has focused on the analysis of end-to-end delays based on worst-case task phasing. However, such analyses are too pessimistic because they do not assume a global clock. With the assumption that task phases can be managed by using a global clock provided by emerging real-time fieldbuses, such as EtherCAT, we can try to calculate the optimal task phasing that yields the minimal worst-case end-to-end delay. In this study, we propose a heuristic to manage the phase offsets in the distributed tasks to reduce the theoretical end-to-end delay bound. The proposed heuristic reduces the search time for a solution by identifying time intervals where actual communication occurs among inter-dependent tasks. Furthermore, to analyze the distribution of endto- end delays in different phases, we implemented a simulation tool. The simulation results showed that the proposed heuristic can reduce worst-case end-to-end delay as well as jitter in end-to-end delays. [ABSTRACT FROM AUTHOR]

The aim of this letter is to improve the performance of clock synchronization in EtherCAT networks. Although EtherCAT synchronizes the slave clocks to the reference clock using a distributed clock synchronization mechanism, a synchronization error still exists between them. We propose a method to estimate and significantly reduce this error. In addition, we implement the method within the existing synchronization mechanism without adding an excessive computational load. The experimental results for synchronization performance verify that the proposed method improves the accuracy of clock synchronization in EtherCAT networks. [ABSTRACT FROM PUBLISHER]

• Coil power supply. • Coil control. • OPCUA. • Ethercat. The Tokamak à Configuration Variable (TCV) coil converters are fed, during the plasma pulse, by a flywheel generator (FG) providing the AC voltages few seconds before the plasma pulse. The synchronization with the 120 Hz frequency delivered by the FG, varying rapidly during the plasma pulse (up to 25 Hz/ sec) is therefore one of the two main challenges of this work. The second one being the extraction of the synchronization signal in presence of the notches on the AC voltages due to thyristors commutations, in order to ensure a proper and accurate firing sequence. This has been solved making use of an innovative implementation of a PLL. Another important feature of this ongoing upgrade is the ability of the controller to be driven by digital voltage references directly transmitted via EtherCAT [1] through the future digital calculator which will ensure the plasma equilibria. Open Platform Communications Unified Architecture (OPC UA) [2] will be used as an upgraded protocol allowing for the TCV Control to interact with the converters interface (HMI). [ABSTRACT FROM AUTHOR]

A numerically controlled processing machine, integrated over EtherCAT with full local redundancy in the axes- to task-space mapping has been designed and built in a laboratory. The redundancy arises from a set of slow, long-ranging base axes manipulating a set of fast, short-ranging tool axes, which again holds and manipulates the tool. The principle of the machine is time-efficient in manufacturing applications with high task detail and where the tool process is faster than the long-ranging axes. This paper will give an overview of construction of the machine and experimental trajectory planning. [ABSTRACT FROM AUTHOR]

Aiming at the structure, expansibility and real-time problems of traditional multi axis controller, the real time Linux system, Machinekit control software and EtherCAT protocol were studied. The composition of Machinekit control software was introduced, and the reasons for the selection of real time Linux operating system were described. At the same time, the structure, real time and stability of multi axis controller were analyzed. On the premise of ensuring the real-time property and stability of the multi axis controller, a software architecture of multi axis controller based on Xenomai and Machinekit was proposed. And the real time Ethernet protocol (EtherCAT) was applied to the controller. To verify controller's function, three servo axes were used, and Wireshark was used to capture the control message to analyze the real-time performance of the system. The results indicate that the controller based on Machinekit and EtherCAT is able to complete the basic control of multi-axis. [ABSTRACT FROM AUTHOR]

EtherCAT has been widely applied in the motion control domain due to its advantages of the fast response speed, low CPU usage and good synchronization performance. Although the built-in distributed clock (DC) synchronization mechanism exhibits strong performance between slaves, the method of clock synchronization between the master and the reference clock is left open for selection by users and there are very few studies in this area. This paper introduces three synchronization modes for EtherCAT and analyzes the reasons for packet loss in free run mode and DC mode. This paper presents a novel method to realize the master clock synchronization with the reference clock. The proposed method can eliminate the settling time which is unusual in other synchronization mechanisms. The method is implemented on Windows with real-time extension and experimental results prove its feasibility. [ABSTRACT FROM AUTHOR]