Radio Frequency Identification technology has been around for a great while now. It originally started being used in the Warehousing and Logistics for Inventory tracking purposes in the mid 2000s, but it never really took over from the good old barcode. The issue here was not so much a maturity of the technology as a per-tag cost of the passive RFID label. In the early 2000s it was between 15¢ and 25¢ per tag, US. Although it may not seem like too much, I cannot compete with 0.2¢ (or sometimes even free) of a regular barcode label. And if you multiply the per-tag amount by the number of individual inventory pieces in a typical distribution warehouse, the price tag can easily reach millions. Since then the prices have been slow to come down, with the average price of a passive RFID tag now sitting at around 10¢. Nevertheless, the only applications where RFID adoption is seeing a true resurgence is on the bulk level (multiple inventory items are stacked on the pallet and tagged under one tag) or with individual items of very high cost. Businesses that go for these types of RFID deployments still work hard on keeping prices per unit relatively small. Data collection in those cases is either fully automated (with RFID gate) or semi-automated (with a worker scanning inventory with some mobile device). Another approach is taken when business sees the value in full automation - when the presence of the worker is completely eliminated from the data collection algorithm. In those cases, mostly on the conveyor, the RFID gate is installed to perform fast, reliable, and fully automated data collection without any human involvement. Last but not least, projects that track equipment usually utilize active tags.
Automating BULK inventory movements in the warehouse
We’ve done a number of projects where Inventory was tracked by a pallet tagged with a passing RFID tag. In one of the larger implementations for a large flower grower, RFID tagged pallets with plastic raw materials were used to track raw material receiving, inventory transfers, warehouse moves, and automated issue of materials to a job. RFID implementation would not only automate product movement, but also speed up quarterly Physical Counts by allowing operators with handheld units to simply walk down the aisle with mobile RFID scanner and scan inventory in only a fraction of time. In the other department of the same company, the final product (flower pots) was loaded onto steel shelf-like carts that were delivered to Home Depot and Lowe’s locations around the country. These carts had hard mounted RFID tags, which were scanned automatically as they were loaded onto the truck or unloaded empty from the truck. This was done to track which retail locations were receiving more flower carts than returning due to mishandling.
Tracking High Cost Items with RFID
We’ve done a number of projects that tagged high cost goods with RFID tags to track the inventory. In one instance, the company that was distributing high priced computer equipment for the Telecom industry would tag the high value items with RFID tags to speed up cycle counts. Interestingly, once the inventory was ready to be shipped, the barcode would be used to record that translation instead of RFID tag because shippers were not equipped with RFID scanners, and high value items were only a small part of the inventory that they were shipping every single day. In another instance, the retailer selling high priced men's clothing was utilizing RFID tags in their stores to simplify check-out scanning, physical counts that were done on a weekly basis, and to automate replenishment. This was a signature project for the high-end retailer, to not only simplify inventory control and point of sale scanning, but also to demonstrate the level of technology and innovation in their stores to the high-end clientele.
Kanban Inventory management with RFID
In my last 15 years working on RFID projects we had two requests for such projects and executed on one such request. In one case, the Kanban # was given to an RFID tag attached to a plastic container that would hold motor oil products. Both Active and Passive tags were looked at for this project. At the end, the client went with the indestructible barcode label instead of RFID as automation was not very high on the priority list. In another instance, the client was the meat processing plant. Each “lot” number of the meat was traveling in the plastic box-like container tagged with active RFID tag playing the role of the Kanban #. As Kanban # was traveling via various conveyors, Work Order operations were recorded based on which RFID gate was crossed. Final production was recorded manually at the last stop of the Kanban container for the inspection and packaging. After being sanitized, Kanban container would be returned to the beginning of the cycle and associated with the next lot number.
Equipment Tracking with Active RFID Tags
Not only are active tags more expensive than passive ones, they also require a battery within the tag, so that they can “broadcast” tag information into the environment. Because of that, active tags are often found in adoption scenarios such as equipment tracking. A heavy construction equipment rental company was trying to complete an RFID project that would utilize active RFID tags for check-out and check-in equipment as well as for inspection purposes. Unfortunately, this project never progressed past the pilot stage due to the client being acquired in a merger with another company that was using a different ERP system.