Going Mobile with RFID Managing Reader Performance in High-Density Metal Environments

By Charles Hermann, Contributing Editor

Avery Dennison launched its Metal Track 915MHz passive reusable tag last March, and is introducing the company's Gen 2 compliant Metal Track II, which is functional in most metal-rich environments. The chip in Metal Track II is sandwiched between two layers of impact-resistant plastic, thus affording durability for any type of interior or exterior application.

Avery Dennison's high-speed production process for Metal Track II enables the company to continuously produce the product consistently and economically, thereby meeting the high volume requirements of any industry. Here, Mr. Herrmann shares his insights about the challenges of metal environments.

Q: What is the #1 challenge that you hear about most from customers working within high-density metal environments?

A: The top challenge that we hear about is related to racking for storage of some kind, transporting mobile racks, or permanent fixed racks. A lot of companies want to know what kind of system is available today that ties an RFID tag into a forklift-type reader. Most companies want automated verification on the transport method, which is typically a forklift. There are systems out there that are either in development or are being commercialized that do just that, and are compatible with durable tags such as Avery Dennison's Metal Track passive 915 MHz RFID tag.

What's the most common misperception about RFID and high-density metal environments?

It's not so much the metal itself that's the problem. A lot of people think that if they just offset the tag a bit from the metal substrate that they'll be able to read it in a metal-rich environment. In some cases that may be true, but in most cases it has more to do with where the tag is positioned relative to how the reader is going to pick up the signal than anything else. It is very environment-specific.

Regardless, metal-dense environments in automotive, retail, and aerospace can also pose specific challenges, such as tag pollution. Tag pollution refers to situations where different kinds of signals create excessive "noise" for readers to perform accurately. In an environment such as that of a distribution site, where hundreds of thousands of racks may be used at a location, tag pollution can become a fairly large issue. Tags today like Metal Track can read up to 15 to 20 feet. In many cases, a user would say, "That's great. I need a long read distance." But in certain environments a long read distance is not necessarily a good thing, as there exists a lot of potential for tag pollution. Tag position may, therefore, become more critical than read distance.

How can a user circumvent tag pollution?

Because each environment is unique, a lot of trial and error needs to take place. There's no set formula to say, "If the area that I'm trying to read within is X square feet, and I've got a read distance of Y, then I need to put the tag at position Z." Position of the tag on the rack or metal component relative to the reader is important. In some cases, the tag can also be designed to read in a narrower range if necessary.

Beyond technology, can you speak a bit about return on investment (ROI) in RFID?

ROI in RFID is something that many users continue to struggle with from the larger perspective. As it relates to reusable tag products, the economics tend to be more attractive, as these tags are more permanent. Item value also needs to be taken into account and the costs associated with misplaced, returned, or lost inventory or shipments.

In some cases, the justification for implementing an RFID system is more intangible than tangible; for example, as it relates to employee efficiency and satisfaction. One of the areas that major retailers have looked at is the problematic nature of barcodes when an employee scans them versus having a mechanized system take care of scanning. I don't know the specifics in terms of incorrect read rates or improper routing of products with human scanning, but my guess is that they're pretty significant. Overall, employee satisfaction and efficiency are key advantages of permanent RFID systems.

Might employee downsizing be a byproduct of RFID implementation?

I haven't heard anything about downsizing workforces. In most cases, I don't think there are plans to do that. I think it comes down more to making sure the data being collected is the correct data, and less about labor cost savings. If an RFID system can do this with the same amount of employees, great. It then will free people to do other work beyond that of scanning barcodes, tracking down pallets, and so on. Employees, in turn, will be more satisfied with their jobs and more efficient as well.

Are the issues being faced by retailers the same as they are for automotive and aerospace?

I believe so. Ultimately it comes down to making sure that you have the right product at the right place at the right time, regardless of industry. I think the potential costs associated with mis-routing or mis-shipping product in the automotive or aerospace environments are much greater on a per unit basis than they are for the retail environment. But the volume of product is also much smaller.

In aerospace, you have a very high value product, so making sure those three criteria are attained means a lot more. So, as the value of the individual unit increases, the potential cost associated with incorrect data causing mis-routing or mis-shipping or poor inventory management is much greater. Durable, reusable RFID tags are a very economical method of attaining that goal.

On the retail side, that's offset by the volume component. The higher the volume on a particular component, the more difficult accurate data collection becomes. Based on those criteria, retail, aerospace, and automotive have been early adopters of durable RFID technologies.

Looking at the RFID space a couple of years out, what needs to happen for companies to fully recognize its benefits? Where is this technology headed?

The real market opportunity as I see it is to be able to reliably read tags automatically with forklift-mounted or portal-based reader systems. That's where systems like those from LXE and Symbol are really going to help drive adoption as they come to market, which they are starting to do. It is the full system, not just tag or reader development, that is the key.

Durable Gen 2 tags and Gen 2 compatible forklift-mountable readers are just now starting to come onto the market simultaneously, and over the next year or two we'll see some standardized systems coming to fruition. That's ultimately the key thing that needs to happen. When it does, we'll see a lot of RFID adoption in a variety of different industries, not just in retail and automotive, but also in areas like food and manufacturing. And with standardization comes lower pricing as well.

Charles Herrmann is Vice President and General Manager of Avery Dennison's industrial and automotive business. Mr. Herrmann can be reached at charles.herrmann@averydennison.com.