No industry without opcua 40

2022-08-15
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Without OPC UA, there will be no industry 4.0

Abstract: the great challenge facing industry 4.0 and industrial IOT (iiot) is information security. Standardized data and information interaction is required between equipment, machines and services in different industries

the great challenge faced by industry 4.0 and industrial IOT is information security. Standardized data and information interaction is required between equipment, machines and services in different industries. As early as April 2015, the industry 4.0 reference architecture model (rami 4.0) only recommended OPC unified architecture (OPC UA) conforming to IEC 62541 standard in terms of communication layer implementation. In November 2016, industry 4.0 released a list of product classification and promotion at different levels of "basically realized", "ready to realize" or "fully realized". In order to adapt to the "industry 4.0 communication" standard, even the lowest category products must be able to address on the network through tcp/udp or IP, and at least the OPC UA information model must be integrated. Therefore, any product advertised as "applicable to industry 4.0" must have OPC UA function (integrated or closed). At the same time, the product list also emphasizes the information modeling attribute of OPC UA

opc UA is not just a communication protocol - it contains more

many small and medium-sized enterprises do not pay attention to information modeling, because these small and medium-sized enterprises always like to compare OPC UA with other protocols (such as mqtt), and take it for granted that it has limitations. Therefore, we often hear such words as "OPC UA cannot communicate directly with the cloud, right?" And so on

first, each device and machine manufacturer has provided an implicit information model with data interfaces (through various protocols). People have learned to adapt to the way computers "think" - recording the meaning of bits, bytes and hexadecimal. The new world is full of various devices. If these devices support service-oriented architecture (SOA), they can help people understand the "thing" itself more quickly and easily, because they can provide "services" and describe its underlying meaning. SOA has long been nothing new in the IT industry, but now, SOA has been extended to the "thing" itself. This is where OPC UA comes into play. It provides a framework for industrial interoperability. Machine and equipment manufacturers describe the object-oriented information of their systems and define access rights and integrated information security functions. In April, 2016, Germany BSI (Federal Institute of information technology or federal information security agency) released a very positive opinion after a comprehensive analysis of the data security of OPC UA. This is because machine manufacturers maintain complete control over data, that is, they can distribute data in a targeted and controllable way, so that they can participate in big data applications and data analysis

in order to exchange data, OPC UA combines two mechanisms to realize various scenarios:

– client server mode, where OPC UA clients access the dedicated services of OPC UA servers. This peer-to-peer approach provides information security and certain information exchange, but there are restrictions on the number of connections

– publisher subscriber mode, in which OPC UA server can be used by any number of subscribers through configuration information subset. This broadcast mechanism provides a "send and discard" information exchange method without information confirmation

opc UA provides these two communication mechanisms, but more importantly, it is independent of the actual communication protocol. TCP and HTTPS can be used in client server mode, while UDP, AMQP, and mqtt can be used in publish subscribe mode. Therefore, the question of "OPC UA or AMQP or mqtt" is irrelevant from the perspective of OPC foundation. Since the smallest microcontroller may not have enough resources to achieve a complete OPC UA, the device can provide data in an "OPC UA compatible" way through mqtt or AMQP, making it easier to integrate to the other end. After all, unifying the meaning of information models and data is the key to achieving industry 4.0

trend: information model

opc UA realizes the safe transmission of data through a variety of extensible protocols, but who defines the meaning of data? Such as the aim Automatic Identification Technology Association (RFID readers, scanners, etc.), VDMA's injection molding machine, robot or machine vision technology group, and 35 other industries involved by VDMA have defined relevant information in OPC UA server, that is, the so-called OPC UA supporting specification. For equipment suppliers, meeting this industry standard does not mean that data can be exchanged, because each manufacturer can add its own special services at the top of the standard. Intelligent devices must be able to support multiple information models at the same time, such as special functions of injection molding machines, as well as energy data models or MES interface models. In order to reduce engineering costs, these information models applicable to specific industries or cross industries will develop rapidly in the future. OPC UA may not directly bring sales growth to industrial equipment suppliers, but if it does not support OPC UA standards, sales will definitely decline significantly

trend: most industry-specific information models currently developed are no longer based on the exchange of bit/byte attributes, but on SOA services with complex parameters. When communicating with OPC UA server, the spot price is high, and the OPC UA client does not support the call of functions or complex parameters will be increasingly limited. RFID readers will no longer activate read-write commands through bits, but use human readable methods to call functions: readtag, writetag, killtag, etc. OPC UA is the ideal choice for the SOA implementation model, which is why the German electrical and Electronic Information Technology Commission (dke) lists OPC UA as the only SOA solution

trend: service to service

opc UA provides consistent scalability from sensors to enterprise it layer, which has a great impact on the automation pyramid. Although this pyramid will continue to exist in the organizational structure of the factory, OPC UA completely bypasses the communication pyramid. The device can directly or in parallel transmit data to PLC, MES, ERP system or cloud. Suppliers see new business opportunities here. For example, the manufacturer can pre install the barcode or RFID on the device, and the customer only needs to scan the barcode or read the RFID information to pay

trend: OPC UA based on chip

OPC Zhongwang has participated in the optimization design of component structure, material experiment, 2D drawing, section improvement, prototype vehicle trial production and other work. UA will continue to be integrated into smaller equipment and sensors. At present, the smallest OPC UA software solution used in the industry only has limited (but readable) functions, requiring only 35 KB of ram and 240 KB of flash memory resources. Now, the first batch of chips with OPC UA function have entered the market, and OPC UA can further enter the sensor market. Therefore, OPC UA application has been extended from the core field of automation to other fields, such as kitchen appliances

opc UA has become the de facto standard of automation market and industry 4.0. Combined with TSN communication, OPC UA will also be real-time. This is not to promote another kind of fieldbus. The market price of graphene is as high as 1million yuan/ton, but to provide a predictable time base for the exchange of SOA services. At the same time, there are still some challenges, such as the configuration of complex TSN network and other problems have not been solved. Therefore, OPC foundation has not actively promoted OPC UA and TSN. Liang Tieshan, chairman of Pingmei Group, also expressed his powerlessness to Caixin in asset disposal. However, OPC UA is covering more and more communication fields, making it more and more difficult for suppliers to judge suitable applications. Products will be distinguished according to the characteristics of the equipment itself or the functions of external services rather than interfaces. In the future, as OPC UA gradually becomes the preferred platform for the world's largest interoperability ecosystem, we will see the rapid development of information models in other industries

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