System design and risk assessment for safety critical control software product lines

A methodology is presented for the design of safety critical product lines for control automation software. The functional failure identification and propagation risk assessment method is used in the early design phase of the mechatronic system. The applied methodology starts with the decomposition of the system into functions that are connected by energy, material and signal flows. This results in a functional model that does not make any assumptions on what components are used to realize the functions. The functions are mapped to mechatronic components in a model that can be simulated: the configuration flow graph. Functional failure logic is executed in parallel to the simulation to monitor the simulation signals and to determine the health of each function. The functional health results of the simulation, when critical events are injected, are used to identify the propagation of functional failures. Alternative designs that are described with a feature model, combinations of component parameter values and changes in the critical event scenario can be simulated. System designs that result in undesirable behavior are rejected. The purpose is to identify risks and to determine mechatronic designs with adequate safety characteristics before the design process branches into software, electrical and mechanical domains. The final deliverable of the mechatronic system design phase is a feature model capturing the design alternatives with acceptable safety characteristics. The aspect of this model containing software is the starting point for software product line engineering. In control automation, programmable logic controller targets are used, so a methodology and toolchain for supporting software product line configuration for such platforms has been developed using the PLCopen standard. Two case studies are used to demonstrate the methodology: a boiling water reactor, with a focus on reactor coolant pumps, and a mobile elevating work platform

Engineering framework for service-oriented automation systems

Tese de doutoramento. Engenharia Informática. Universidade do Porto. Faculdade de Engenharia. 201

Maintainability and evolvability of control software in machine and plant manufacturing -- An industrial survey

Automated Production Systems (aPS) have lifetimes of up to 30-50 years, throughout which the desired products change ever more frequently. This requires flexible, reusable control software that can be easily maintained and evolved. To evaluate selected criteria that are especially relevant for maturity in software maintainability and evolvability of aPS, the approach SWMAT4aPS+ builds on a questionnaire with 52 questions. The three main research questions cover updates of software modules and success factors for both cross-disciplinary development as well as reusable models. This paper presents the evaluation results of 68 companies from machine and plant manufacturing (MPM). Companies providing automation devices and/or engineering tools will be able to identify challenges their customers in MPM face. Validity is ensured through feedback of the participating companies and an analysis of the statistical unambiguousness of the results. From a software or systems engineering point of view, almost all criteria are fulfilled below expectations

Software methodologies for the engineering of service-oriented industrial automation: the continuum project

Indexado InspecService-orientation represents a new wave of features and solutions by bringing closer Information Technology to the industrial domain, particularly factory shop floors. The service-oriented automation software entities (designated here by bots) used in such approach requires a short set of methodologies and software targeting their specification for both computer systems and embedded automation devices. The present work explains the adopted methodologies and software developments for the engineering of service-based automation systems. The main contents focus on the specification of a framework for the development of bots and supporting engineering tools that are part of the Continuum project. The paper also does an overview over the engineering steps from the system design to the operation, and focuses the importance of the maintenance of automation bots. Such applications will contribute to decrease the development time and reduce the components' interdependency, offering enough flexibility for automatic reconfiguration of shop-floor layouts.The authors would like to thank the European Commission and the partners of the EU IST FP6 project “Service-Oriented Cross-layer infrastructure for Distributed smart Embedded devices” (SOCRADES), the EU FP6 “Network of Excellence for Innovative Production Machines and Systems” (I*PROMS), and the European ICT FP7 project “Cooperating Objects Network of Excellence” (CONET) for their support

Modularity and Architecture of PLC-based Software for Automated Production Systems: An analysis in industrial companies

Adaptive and flexible production systems require modular and reusable software especially considering their long term life cycle of up to 50 years. SWMAT4aPS, an approach to measure Software Maturity for automated Production Systems is introduced. The approach identifies weaknesses and strengths of various companie's solutions for modularity of software in the design of automated Production Systems (aPS). At first, a self assessed questionnaire is used to evaluate a large number of companies concerning their software maturity. Secondly, we analyze PLC code, architectural levels, workflows and abilities to configure code automatically out of engineering information in four selected companies. In this paper, the questionnaire results from 16 German world leading companies in machine and plant manufacturing and four case studies validating the results from the detailed analyses are introduced to prove the applicability of the approach and give a survey of the state of the art in industry

A service-oriented approach to embedded component-based manufacturing automation

This thesis is focused on the application of Component-Based (CB) technology to shop oor devices using a Service Oriented Architecture (SOA) and Web Services (WS) for the purpose of realising future generation agile manufacturing systems. The environment of manufacturing enterprises is now characterised by frequently changing market demands, time-to-market pressure, continuously emerging new technologies and global competition. Under these circumstances, manufacturing systems need to be agile and automation systems need to support this agility. More speci cally, an open, exible automation environment with plug and play connectivity is needed. Technically, this requires the easy connectivity of hardware devices and software components from di erent vendors. Functionally, there is a need of interoperability and integration of control functions on di erent hierarchical levels ranging from eld level to various higher level applications such as process control and operations management services. [Continues.

OPC UA support for Beremiz softPLC

Integração do protocolo de comunicação para Automação Industrial OPC UA no softPLC Beremiz, o qual segue a norma IEC 61131-3. Mapeamento dos elementos definidos no IEC 61131-3 para OPC UA utilizando como guia a especificação criada pela OPC Foundation em conjunto com a fundação PLCopen "OPC UA Information Model for IEC 61131-3".Integration of the Industrial Automation protocol OPC UA in the IEC 61131-3 compliant Beremiz softPLC. The mapping between IEC 61131-3 elements and OPC UA will follow the "OPC UA Information Model for IEC 61131-3" specification

An approach to task coordination for hyperflexible robotic workcells

2014 - 2015The manufacturing industry is very diverse and covers a wide range of specific processes ranging from extracting minerals to assembly of very complex products such as planes or computers, with all intermediate processing steps in a long chain of industrial suppliers and customers. It is well know that the introduction of robots in manufacturing industries has many advantages. Basically, in relation to human labor, robots work to a constant level of quality. For example, waste, scrap and rework are minimized. Furthermore they can work in areas that are hazardous or unpleasant to humans. Robots are advantageous where strength is required, and in many applications they are also faster than humans. Also, in relation to special-purpose dedicated equipment, robots are more easily reprogrammed to cope with new products or changes in the design of existing ones. In the last 30-40 years, large enterprises in high-volume markets have managed to remain competitive and maintain qualified jobs by increasing their productivity with the incremental adoption and use of advanced ICT and robotics technologies. In the 70s, robots have been introduced for the automation of a wide spectrum of tasks such as: assembly of cars, white goods, electronic devices, machining of metal and plastic parts, and handling of workpieces and objects of all kinds. Robotics has thus soon become a synonym for competitive manufacturing and a key contributing technology for strengthening the economic base of Europe . So far, the automotive and electronics industries and their supply chains are the main users of robot systems and are accounting for more than 60% of the total annual robot sales. Robotic technologies have thus mainly been driven by the needs of these high-volume market industries. The degree of automation in the automotive industries is expected to increase in the future as robots will push the limits towards flexibility regarding faster change-over-times of different product types (through rapid programming generation schemes), capabilities to deal with tolerances (through an extensive use of sensors) and costs (by reducing customized work-cell installations and reuse of manufacturing equipment). There are numerous new fields of applications in which robot technology is not widespread today due to its lack of flexibility and high costs involved when dealing with varying lot sizes and variable product geometries. In such cases, hyper-flexible robotic work cells can help in providing flexibility to the system and making it adaptable to the different dynamic production requirements. Hyper-flexible robotic work cells, in fact, can be composed of sets of industrial robotic manipulators that cooperate to achieve the production step that characterize the work cell; they can be programmed and re-programmed to achieve a wide class of operations and they may result versatile to perform different kind of tasks Related key technology challenges for pursuing successful long-term industrial robot automation are introduced at three levels: basic technologies, robot components and systems integration. On a systems integration level, the main challenges lie in the development of methods and tools for instructing and synchronising the operation of a group of cooperative robots at the shop-floor. Furthermore, the development of the concept of hyper flexible manufacturing systems implies soon the availability of: consistent middleware for automation modules to seamlessly connect robots, peripheral devices and industrial IT systems without reprogramming everything (”plug-and-play”) . In this thesis both innovative and traditional industrial robot applications will be analyzed from the point of view of task coordination. In the modeling environment, contribution of this dissertation consists in presenting a new methodology to obtain a model oriented to the control the sequencing of the activities of a robotic hyperflexible cell. First a formal model using the Colored Modified Hybrid Petri Nets (CMHPN) is presented. An algorithm is provided to obtain an automatic synthesis of the CMHPN of a robotic cell with detail attention to aircraft industry. It is important to notice that the CMHPN is used to model the cell behaviour at a high level of abstraction. It models the activities of each cell component and its coordination by a supervisory system. As more, an object oriented approach and supervisory control are proposed to implement industrial automation control systems (based on Programmable Logic Controllers) to meet the new challenges of this field capability to implement applications involving widely distributed devices and high reuse of software components. Hence a method is proposed to implement both controllers and supervisors designed by Petri Nets on Programmable Logic Controllers (PLCs) using Object Oriented Programming (OOP). Finally preliminary results about a novel cyber-physical approach to the design of automated warehouse systems is presented. [edited by author]XIV n.s