Our warehouse does not use RFID, but we are now ready to implement the technology. What hardware and software would be required to make our warehouse smart?
There are different ways you could do this, depending on what you were trying to achieve. The first issue you would need to address would be tagging goods arriving at your warehouse. If the facility were to receive goods that were tagged, then you could set up RFID reader portals at the receiving bays and read the tags on the items. You would need advance shipping notices with item descriptions or serial numbers and associated tags. That way, you could match what you were expecting to receive with what you actually received.
If the items arriving were not tagged, you would need to tag them at the warehouse. That would mean taking a list of what was expected to be received, applying tags and matching each tag ID to a particular item in a database. For example, a box of hex bolts would arrive, and you would put an RFID tag with serial number 1234567890 on it. In your database, you would need to associate that serial number with that box of hex bolts, so that when the tag was read, you would know you had located that specific box of bolts.
All tagged items would be put on a shelf, but let's leave aside for a moment the issue of finding items on a shelf, because there are different ways to do this with RFID. Eventually, the warehouse would receive an order and the items would be picked and readied for shipment. You could install RFID reader portals at the shipping bays and read all tags as goods were loaded onto on a truck. The tag reads would be matched against a shipping order or manifest to ensure that only the correct items were put on the truck. If an item turned out to be missing, software could alert workers to that fact. If the wrong item were put on the truck, an alert could sound to notify employees to remove it and replace it with the correct item. This would help to ensure 100 percent shipping accuracy.
What would happen between receiving and shipping would depend on whether you wanted real-time visibility or were content to search for an item when it was needed. Some companies require real-time visibility and put overhead readers in their warehouse to constantly read items on shelves and provide location information. Other firms prefer not to invest in such a fixed infrastructure and instead use handheld readers. In such a scenario, a worker walks around a warehouse waving a reader, which beeps louder as he or she approaches the desired item. Some companies scan a bar code on each shelf to record that shelf's location and link it to the RFID tag ID.
In the case of overhead readers, you should be able to achieve an accurate inventory count at any given time. If you used a handheld unit, you should be able to know what was in the warehouse because tags would be read or applied as items came in. But you could also update inventory by having workers walk up and down aisles to interrogate all products' tags.
Keep in mind that reading tags consistently will depend on the type of item and how it is tagged and oriented within your warehouse. If you had items that were made of metal or contained a lot of water, it could be a challenge to read the tags. Metal can block energy from reaching or returning from a tag, while water absorbs RF energy, preventing signals from reaching the tag. So if you had these types of items in your warehouse, you would need to tag goods in such a way (or with a specifically designed tag) so that each tag could be read.
You would also need to orient the items so that all tags were in a position to be read. If you were to put an on-metal tag on the top of a metal drum and then stack another metal drum on top of it, the signals would not reach the tag. If the on-metal tag was on the side of the drum and no other drum was directly in front of it, then it should be readable.
I hope this proves helpful.
—Mark Roberti, Founder and Editor, RFID Journal
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