Distributed Real-Time Control Systems using CAN

Embedded control systems usually are characterized by its limitations in terms of computational power and memory. Although this systems must deal with perpection and actuation signal adaptation and calculate control actions ensuring its reliability and providing a certain degree of fault tolerance. The allocation of these tasks between some different embedded nodes conforming a distributed control system allows to solve many of these issues. For that reason is proposed the application of smart devices aims to perform the data processing tasks related with the perception and actuation and offer a simple interface to be configured by other nodes in order to share processed information and raise QoS based alarms. In this work is introduced the procedure of implementing a smart device as a sensor as an embedded node in a distributed control system. In order to analyze its benefits an application based on a RGBD sensor implemented as an smart device is proposed.

7 - Distributed control systems (DCS)

Distributed Control System (DCS) has been widely recognized in the field of modern thermal power thermal control, and has significant effects in the application process. Today, the monitoring of electrical quantities is included into the DCS system, thus replacing the traditional "one to one" manual mode of operation in electrical control. It is to further improve the main works of the station automation and control systems. Combined with the actual project needs, this study focuses on the components of electrical control included in DCS system, the implementation of software and hardware features, and the measures to improve reliability. In addition, useful discussions have been made for some technical problems. In the DCS system, the electrical control inclusion is not just a perfection thermal power plant electrical control system, but a big improvement as well. In addition, it is a new attempt. At present, most of the electrical control parts of control system included into the DCS system with the manual operation are basically cancelled, but there are some problems, for example many of the designs do not match with the original operating habits, etc., which will have a certain impact on the tradition. In the transformation process of system, some of the designs are good but cannot be achieved currently. They still need further research and improvement, for example how can the electrical control of system enter into the DCS in a better manner, how can the display of light texts upon failure or abnormal time weaken electric signals in a more comprehensive and rapid manner, what are the new requirements for anti-interference, and other sequential control functions to be improved and perfected.

Within industry today, advancements in process and control technologies have given way to differing control systems in the form of programmable logic controllers (PLC) and distributed control systems (DCS). Over the past decade, PLCs have now been able to bridge certain gaps within process and control systems that were capabilities only typically found within DCS environments. This paper will provide an overview of various control system strategies and design considerations with regard to both PLC and DCS schemes within petrochemical applications.

Smart devices have been developed and widely used recently, so they have been applied in the industrial field. If mobile technology is applied to the CAD field, users will be able to obtain many advantages such as high mobility and ease of collaboration. To develop a feature-based CAD system that can be made available on smart devices, we suggested a system using multi-touch inputs in 2012; this was a stand-alone system available without a network. However, the system could not create complex shapes by itself because of the absence of a modeling kernel for the mobile platform and the low computing power of smart devices. To solve this problem of shape creation, this study proposes a client-server system for CAD systems on smart devices. When modeling commands are created from drag-type buttons, at each step, the analyzed modeling commands are sent to the server, the server creates the model and sends it to the smart device, and the smart device visualizes the modeling result. This system can make more complex models than those possible with the existing system. This study compares the developed system with the existing system in order to verify the usability of the new CAD system on smart devices; further, this study suggests how to extend this system to collaborative systems. This CAD system for smart devices can increase the mobility and cooperative nature of CAD systems.

Digital twins present revolutionary potential in smart manufacturing and production. However, their current application in distributed control systems is minimal and largely unexplored. By applying digital twins to distributed control systems, distributed intelligent sensing and control systems may be achieved. These systems are fully automated and self-managing, making them a valuable asset.In this paper, we provide a short literature review which establishes the definition, application, and implementation of digital twins in smart manufacturing and production. Based on this review, we propose their application in transforming distributed control systems into distributed intelligent and sensing control systems. We identify features of a digital twin which will be of greatest use in a distributed control system, and discuss our current research direction aimed at interfacing these control systems with digital twins.KeywordsDigital twinSmart intelligence distributionControl system

Remote control process system with distributed time-delay has attracted much attention in different fields. In this paper, non-linear remote control of a single tank process system with wireless network is considered. To deal with the distributed time-delay in a large-scale plant, the time-delay compensation controller based on DCS devices is designed by using operator theory and particle filter. Distributed control system (DCS) device is developed to monitor and control from the central monitoring room to each process. The particle filter is a probabilistic method to estimate unobservable information from observable information. First, remote control system and experimental equipment are introduced. Second, control system based on an operator theory is designed. Then, process system with distributed time-delay using particle filter is carried out. Finally, the actual experiment is conducted by using the proposed time-delay compensation controller. When estimating with the proposed method, the result is close to the case in which the distributed time-delay does not exist. The effectiveness of the proposed control system is confirmed by experiment results.

In the distributed control system, it is not easy to communicate between different operating systems due to the different control platforms. Therefore, the control system is difficult to repair and upgrade. In this study, we employ Timed Petri Net to build up architecture of the real-time control system. The client not only can monitor the current status of production line via the World Wide Web in the OEM plant but also can allow equipment supplier to perform supervision, analysis, and repair in the real-time state. The operation of the hardware platform that is no longer limited to the personal computer (PC) can also support the use of PDA(Personal Digital Assistant) , and internet browsing hardware, and web site monitoring system connected through the web page to monitor the purpose of monitoring equipment machine.

Research on Key Technologies of Multi-smart-agents Based Partially Distributed Control System for Aero Engine

This paper presents the design and simulation of a reliable data communication network. Real time data communication network with high load File Transfer Protocol (FTP), database access, E-mail and Voice over IP (VoIP) with PCM quality application are simulated subject to reliability study. OPNET Modeler 14.5 is used as network simulator. Many models are considered in the simulation and tested against many cases (high load, utilization factor of links, network topological change). The simulation results are analyzed and discussed based on the case study of building an Intranet for the North Oil Refineries of Baiji (NORB) in Iraq. This paper deals with performance evaluation of industrial plant Intranet used to interconnect several Distributed Control Systems (DCS) and the evaluation of real-time parameters describing the behavior of the network. © 2012 IEEE.

A methodology for static and dynamic scheduling of automation tasks in reconfigurable production systems

Emerging IT technologies, specially Internet communication and webbased technologies are adopted to the modern distributed control systems. This paper defines a functional framework for the webbased applications of a distributed control system connected by Internet. XML(eXtensible Markup Language) is used for representing a control system and control devices. These IT technologies make a distributed control system more flexible and scalable than existing distributed control systems with the standard RMI protocols such as CORBA or DCOM.

This paper aims to focus on database configuration of process control systems during project engineering phase and the impact of initial configuration on their performances and lifetime. We will start by highlighting operation principle of such systems, taking as example DCS systems (Distributed Control Systems) where we discussed their hardware and software architecture evolution and then identify the most common problems encountered on these systems. Through a case study, we will focus on the optimization of database configuration and see how could bad configuration practices reduce the control system performances and then may affect industrial process operation. The case study discussed is about a DCS system installed to control oilfield processing facilities where hardware and software description on this control system is given. We will emphasize on system deficiencies which the most important of them is the problem of database memory saturation which causes significant system performances and lifetime decreases.KeywordsProcess control system (PCS)Distributed control system (DCS)Database configurationMemory saturationSystem performance and lifetime

This paper presents the distributed control system for elevators (DECS). Based on the characteristics of the today installed elevator systems, the electric traction elevator has been chosen for this paper. Conventional elevator control systems (ECS) have several disadvantages compared to modern control systems (large number of cables, safety issues, etc.). An alternative to conventional ECS is the DECS. A DECS based on the CAN (Controller Area Network) protocol is presented in this paper. The presented ECS consists of three modules: CU Elevator (CU - Control Unit), CU Cabin, CU Floor. The mentioned modules, control principles and implementation methods based on the PIC 18F458 microcontroller are presented in detail. A description of the CAN protocol design with message scheduling on the bus is given. Messages with an 11 bit identifier without a data field have been used for the distributed control system synthesis. The time analysis of bus availability/traffic demonstrates the adequacy of the distributed control system Based on the defined messages and 5 presented modes of operation, an algorithm of operation has been formed for every control system module. Finally experimental results are presented that have been obtained from a developed CAN based elevator control system. The conducted tests have confirmed the functionality of the elevator control system.

The distributed control system (DCS) is the most prevalent means of implementing batch and continuous control in the process industry. The DCS platform may also be effectively used for the evaluation and demonstration of innovative algorithms developed at a university. The integrated online advanced controls, diagnostics, data analytics, and process modeling capability of a DCS facilitate university research. This working environment also prepares students for careers in industry. The paper discusses the industrial standards adopted by the DCS that allow students and researchers to concentrate on the application of new control capabilities. External applications such as Matlab can be used with the DCS to explore control and process modeling. In this environment, the student and researchers may take advantage of preconfigured and automated features of the DCS. Process simulations may be integrated into the DCS to create a virtual plant capability that is capable of running faster than real-time. The DCS supports wireless and internet access to the virtual plant which increases ease of use in a lab or pilot plant. The DCS system enables rapid exploration, discovery, and prototyping of process modeling and control technologies in a university environment and deployment in industry.