RFID Replaces Bar Codes for Efficient Asset Tracking

Bar code technology has been around for many years and is a tried and true means for tracking asset and product movement, but it has its limitations. For example, a bar code reader must have an unobstructed view of the bar code to effectively scan. And the bar code label cannot be damaged, or it is then unreadable by the scanner.

In more recent years, additional RFID technologies have been more readily available for use to accomplish the same task but with fewer limitations. Using RFD, a scanner may be able to read tags that are blocked by other things and not visible to the naked eye. UHF RFID can scan multiple tags at the same time in a single scan, whereas most bar codes need to be scanned individually. This, therefore, increases efficiency and reduces the time required to perform the scans.

Then, of course, there is the human factor. RFID can help eliminate mistakes caused by human error. Most bar code scanning is done with hand scanners held by workers since the scanner has to be in the exact position to see the bar code to get a good scan. While manual/hand-held scanning can be done using RFID, most times a fixed scanner can be used as long as the position of the RFID tag can be guaranteed within certain tolerances. These tolerances are much greater than with a bar code scanner.

With the advent of inexpensive consumable RFID labels, the ease and cost of transitioning to RFID technology has become more feasible for manufacturers and end users. These labels can be purchased for pennies each in rolls of several thousand at a time.

It should be noted that several companies now produce printers that can actually code the information on a RFID label tag while also printing data, including bar codes, on these label tags so you have the best of both worlds. Tags can be scanned automatically and data that can be read by the human eye as well as a bar code scanner.

Some companies have expressed concern about the usage of RFID in different countries due to local regulations regarding the frequencies of radio waves causing interferences.

This is not an issue for HF  and UHF technology. HF is an ISO standard (ISO 15693) technology so it applies to most everywhere. For UHF, which is more likely to be used due to the ability to scan at a distance and scan multiple tags at the same time, the only caveat is that different areas of the world allow scanners to only operate in certain frequencies. This is overcome by the fact that almost all UHF tags that I have encountered are what are called global tags.

This means these tags can be used in any of the global frequency ranges of UHF signals. For example, in the North America, the FCC restricts the frequency range for UHF RFID scanners to 902-928 MHz, whereas MIC in Japan restricts them to 952-954 MHz, ETSI EN 300-220 in Europe restricts them to 865-868 MHz, and DOT in India restricts them to 865-867 MHz. These global tags can be used in any of these ranges as they work from 860 to 960 MHz.

On the subject of UHF, it should be mentioned that in addition to the frequency ranges restricted by various part of the world, maximum antenna power is also locally restricted.

For more information on RFID for asset tracking, visit https://www.balluff.com/local/us/products/product-overview/rfid/

 

QR Codes for Business vs Industry

QRCode
Example of a QR code for business use

In a previous post I discussed the different types of bar codes. Aside from the 1D bar codes that we see in the grocery store, the most common type of bar code today is the QR code.

The QR code was 1st designed for the automotive industry to track vehicles in the assembly process. The QR code system became popular outside the automotive industry due to its greater storage capacity compared to standard UPC bar codes. A QR code can have up to 7,089 ASCII characters and can read numeric, alphanumeric, byte/binary, and kanji. Businesses often use this type of QR code on vehicles and products for advertising. When a picture is taken with a cell phone, typically in a QR code reader app, the user will be taken to a website for more information.

Sharpshooter vision sensor for reading micro & QR codes
Sharpshooter vision sensor for reading micro & QR codes

Micro QR codes, on the other hand, have a limitation of 35 digits of numeric characters. These are usually seen in industrial applications. For example, they are seen on cam shafts, crankshafts, pistons, and circuit boards. An example of data that is often written to a micro QR code would be a serial number to track and trace through an assembly plant. An industrial vision sensor is typically needed to decipher micro QR codes.

ILoveBalluffQRCodes
An example of a QR code (left) vs a micro QR code (right)

For more information visit www.balluff.us.