Scanning the horizon

It's only a few short years since RFID (radio frequency identification) was being touted as tomorrow's technology, ready and waiting to spearhead an auto-identification and tracking revolution. Manufacturers and retailers alike would find their operational efficiencies metamorphosed; supply chains would bristle with data trails for stakeholders to consume; and even returns and recalls would become mere costly nuisances, no longer the stuff of nightmares. But, despite the lure of wireless, non-contact identification of pallet loads of multiple product types, all without human intervention, it just didn't happen. Even the infamous Wal-Mart initiative – in which suppliers to the global megastore would implement RFID or count themselves out – largely failed to get off the ground, dogged by difficulties in realising workable return on investment for all but a few. In the event, conferences, workshops, analysts' white papers, demonstrators and a raft of new media all promised much, but delivered precious little. And so, a world finding its fingers somewhat scorched largely turned away. But not back – because a profound change came out of the RFID hype years. In a nutshell, business leaders' perceptions of the value of auto-identification projects, at whatever level (pallet, case or item), had been tipped over the edge – and voice technology and barcode implementations have since been the main beneficiaries. On the one hand, barcode-based data collection is now increasingly seen as central to supporting flexible, responsive and accurate production – particularly when allied to advanced planning and scheduling and/or manufacturing execution system implementations. And on the other, it is much more widely recognised for its capacity to help drive and sustain continuous improvement – for example, by enabling operations to cement in real, rather than planned, production times or pass/fail rates (see box item, p45). But why exactly has RFID moved into the realms of high-value niche solution? Partly, it's the sheer cost of the equipment and infrastructure required, including the RFID tags (whichever technology is selected). And partly it's the scale of project engineering required. John Williams, marketing manager at CoreRFID, points out that although UHF tags have dropped in price by about 70% over the last few years, they're still close to £1 each. So RFID has to solve serious problems to make it worthwhile. But, just as important, he also reminds us that there is a range of technologies and few standards in RFID, so installations are largely bespoke and you certainly won't find much equipment capable of reading all, or even many, tag types. "The main practical issue is that you're using radio signals to energise and fetch data from a chip. So anything that interferes with those signals or your wireless infrastructure – in the environment, the product itself or the packaging – will affect detection rates and workable distances. That's why you have to design and tune every RFID installation for the particular situation," explains Williams. "If, for example, you're talking about metal products on metal carriers or in metal cages, then the way you set up a reader portal is very different to, say, a system for detecting big bags of compost on wooden pallets, wrapped in plastic." And a further challenge: "Once you've got RFID working within your own four walls, there's no guarantee that it will work as well anywhere else – say, downstream in the supply chain," states Williams. That's why practically no one is checking product types and numbers out using RFID through loading bays, and then in via portals for automatic receiving elsewhere. As Raju Surendra, general manager of manufacturing business software giant Infor's barcode group, puts it: "For RFID to work well, shopfloors and warehouses need a lot of engineering, in terms of the infrastructure and the tags. And it's the same for the supply chain. But, for the most part, all the automation and traceability you want can be achieved through barcodes." No surprise then that manufacturers tend only to think about RFID when they encounter something unusual that just can't be handled by more readily accessible scanning technologies. Williams doesn't go quite as far as describing RFID as a solution waiting for a problem, but it's close. However, the flip side is that, where RFID is successfully engaged, those manufacturers are likely to have gained significant competitive advantage. Hence the very few manufacturers prepared to put their hands up and offer anything like chapter and verse on their implementations. Indeed, the only RFID user of any note prepared to talk on the record to this journal was boiler manufacturer Vaillant (WM July 2010, p24). That said, despite having been covered in these pages, Vaillant's story is worth just a little expansion to demonstrate both its reasons for doing it and the benefits achieved. "What I wanted to do was create a system that forced process control down our production line, but also recognised the fact that everyone is different – so didn't overly manage the way technicians do the build," explains Richard Sainsbury, industrial engineering manager at Vaillant. Readers will recall that we're talking about a one-man build process, where boiler chassis move on trolleys through production stages, with operations performed at each depending on customer configuration. "I thought, for example, about locking systems, with shot bolts that only release when all work is completed at each stage. But that would limit the ergonomics and it wouldn't be flexible. So then we thought about barcodes… but there could be problems with labels getting scratched, reader errors, etc. RFID, on the other hand, would be wireless and seamless – and we knew that by adding more data transfers we could expand the system, for example, to include tool management." For him, RFID was a natural and indeed an empowering solution. Now, at the start of each build, everything – from the boiler serial number to the trolley it stands on and the person building it – is logically linked. RFID portals track where boilers are and which assembly operations are being performed – not only enabling the right tools to be powered up and correct instructions given for each boiler build, but also reminding technicians of previous omissions and preventing errors. It even enables line balancing to be performed, ironing out bottlenecks on the fly. But Sainsbury warns of several practical points such as the scale of trials required to get it right, and the eventual choice of reusable battery-assisted power tags as a halfway house between passive and active, to get consistent read rates. He also says that Vaillant went for a separate local LAN, taking daily parameter downloads, to ensure resilience. And he points to special measures taken to limit wireless activity at the portals, so eliminating any possibility of interference in what is a tightly packed production hall. "Attenuating signal power and cutting down on the number of broadcasts was important for us," he says. "We also toyed with the idea of RFID being the data device and driving the build processes itself, but decided that the tag read/write processes would risk slowing down production." Generalising then, Vaillant's implementation is all about programming and reprogramming tags in a closed loop production chain, effectively enabling very efficient and flexible factory operations. So successful has it been that Sainsbury says the firm is now rolling out RFID to all other plants in the group. Other manufacturers that claim comparable benefits are typically those involved with high value bespoke products that are periodically returned – for example, for maintenance. Here, it is the tags' ability to immediately identify precise detail, such as component types, serial numbers or sizing, that is the big deal. Others also using ROI include those producing high value items where the concern is theft or counterfeiting. And others, again, are companies delivering product in expensive reusable carriers, such as totes or barrels, in closed loop supply chains. Those are the classics. Other applications include those where products need to be tracked through processes involving heat, aggressive chemicals, moisture or difficult packaging – anything that could lead to barcode labels being damaged or obscured, but which leave RFID tags unscathed. CoreRFID's Williams cites one project involving car bumper manufacturing, where processes had to be monitored through curing ovens and then product synchronised by colour and type with vehicle production on the main line. At a much simpler level, he also mentions a potting compost manufacturer currently working on RFID. "Before this company's pallets leave the production line, they're shrouded in opaque material to prevent deterioration of the product in sunlight – so that covers up all the labels," he explains.