Identification and traceability within the production chain are increasingly important and decisive in the automotive and logistics industry. The need to build automated, articulated and flexible machines and assembly lines, with high production volumes, ever smaller batches and an equally high-quality standard, has compulsorily directed manufacturers of automated technologies specialized in handling, handling, processing or assembly, towards the use of radio frequency identification systems.
by Gruppo Meccatronica di ANIE Automazione
A decentralized and networked production with integrated intelligence can only work with a constant high volume of information, along the entire supply chain and with related objects. Implementing this concept within a production plant means having to process a large amount of sensor data, but also performing identification tasks. Since communication with the products must be simple, cost-effective, at all times and throughout the production and processing process, RFID solutions are an important part of the production chain, which can overcome or prevent problems and malfunctions affecting production costs; verify the correct composition of the assembled parts; control processing times and methods; strengthen worker safety; monitor the health of the machines with a view to energy savings and optimal maintenance cycles. The improvement of the yield and quality profile of the goods produced is also one of the motivations supporting traceability in production: having a continuous and truthful perception of the various departments and the progress of each individual piece, providing real-time information related not only to the production process, but also to the correct and timely processing of orders and therefore customer satisfaction, is part of a lean approach to production. The possibility to identify, select and manage the resulting data is fundamental in order to make the information flow consistent and really usable, which are increasingly the critical resource of Smart Manufacturing. RFID in this context is, therefore, an important and pervasive technology, and just these last few years have seen a strengthening of its growth trend, thanks also to the measures of the Industry 4.0 National Plan that encourage companies to invest in new capital goods and innovative technologies.
Advantages of RFID technology in the automotive market
In the automotive market, every single user can decide on countless details of his new car, from the bodywork and painting variants of the individual parts, to the fittings and optional extras. This is the reason why it is necessary a traceability solution that can cover the entire production cycle of the car, from the bodywork to the final test, passing through the various painting and assembly treatments. The technology that best adapts to these requirements is RFID UHF, which allows to identify the cars in production, applying a special RFID label (tag) directly to the vehicle bodywork.
The application experience described below is a concrete example of the advantages offered by RFID solutions in the automotive sector compared to other identification methods.
The vehicle manufacturer initially used RFID tags on the media that housed the vehicle at various stages of processing, but since each stage requires a specific media, there was a risk of losing track between stages if the bodywork/support coupling is not properly registered or if the bodywork is decoupled from the support.
By means of an RFID tag designed to withstand all the difficult environmental conditions encountered in production (chemicals, paints, heat) it was possible to keep track using only one support.
The tag is designed to be disposable, so it is eliminated at the end of production or left on the vehicle to be used for traceability also in the logistic phases after production, for example, for the identification of the entrance exit from the parking yards and the loading and unloading on the caravans for transport. In fact, the RFID tag is applied to the body by means of a plastic support, which allows a safe and correct distance with the metal. The tags are selected according to size, type of support, IP rating, working temperature and son on.
The technological development aimed at miniaturization of RFID antennas has saved space, time and money in logistics applications (e.g. for pallet entry/exit portals) and for vehicle identification.
In the automotive case, it is necessary to use tags resistant to high temperatures (> 230°C) that allow the RFID chip inside not to be damaged even when diving in body treatment baths containing aggressive chemicals.
The tag’s cost-effectiveness is paramount for manufacturers and it should not excessively affect production costs.
Reading reliability is a fundamental requirement
The use of UHF RFID technology, which guarantees the greater reading distances achievable in passive RFID, allows the positioning of the reading stations so that they are not an obstacle to movement and guarantees a wide reading area, giving the possibility to manage also different models and bodies without having to reposition the reading antennas. Reading reliability is a fundamental requirement for the user. Once the data are correctly read, they must be made available to the MES system that manages the entire production. Readers have the ability to communicate read data directly to ERP and MES systems, via standard high-level Ethernet protocols, such as OPC UA. In this way the interface between the OT world of sensors and the IT of industrial software is very simplified and easily manageable.
The capillarity of the reading stations makes it possible to have much more statistical data available to improve production, such as processing times for each phase and the occurrence of cases requiring rework, with a consequent improvement of the process and the possibility of preventive maintenance.
This is the reason why the use of the RFID solution is not limited to certain application fields but to any important component in any field (e.g. logistics industry) that can be traced.
The technology described lends itself, in fact, to be applied also in many other production lines. Thanks to the use of readers and labels conforming to the international standard EPCglobal UHF Class 1 Generation 2, ISO/IEC 18000-6 C, it is possible to use the same tag and the same reading technology throughout the supply chain and logistics, even if made by different companies.