The warehousing problem
Everyone who runs a warehouse knows that space is expensive, stock is expensive – and even more expensive when it gets moved and you lose track of it. Having employees manually walk around the warehouse to locate products poses a huge resource cost for manufacturing companies.
Turck Banner and its sister company, Turck Vilant, have a unique track-and-trace system that can tell you what is in your warehouse and where it is in real time. This works by combining radio-frequency identification (RFID) with a real-time live location system (RTLS). This means that products are not only tracked when they enter and leave the warehouse, but are also easily identified throughout their entire life cycle within the warehouse.
The limitations of traditional methods
The simplest warehouses often use shelf locations in alphanumeric order, with one location for each product. This is very inefficient in terms of the space requirement, as a location is required regardless of whether there is currently any stock or not.
Gaps must be left for new products to be accommodated between current locations, or for larger quantities of the current items to fit in the correct location. This system doesn’t require any form of tracking beyond goods in and goods out, but is the most prone to errors and misplaced items.
A chaotic warehouse system has numbered locations which get filled based upon quantity and product dimensions, not part numbers. The system keeps track of what product is in which
location, and directs the warehouse person either to place items in a location or pick from a location. This solution is a much more efficient use of space, as every location can be used by any product. However, it is still reliant on a person using the correct location and not moving anything.
Barcodes
Often, these two systems are combined with a barcoding solution, where every product carries a barcode and the warehouse person scans the barcode of each item, when they pick or place the item in a location. This confirms that the correct item is selected, but is still vulnerable to items being moved or removed without the system’s instruction.
Errors also commonly occur when a warehouse person scans the same item multiple times instead of correctly scanning each similar item. For example, when they are instructed to pick three of item A, they scan the first barcode three times, but have actually picked up two of item A and one of a different item, as many products look similar.
Barcodes can only be read at close range, one at a time and in direct line of sight, which limits their use where large quantities are involved.
RFID tags
By contrast, RFID tags can be read from a greater distance, do not need a line of sight, and multiple tags can be read at the same time. This allows a whole pallet of goods to be inventoried without removing any items from their containers.
There
are standards for the data content of RFID tags defining: products, shipments and assets, allowing shipments from multiple suppliers to be received without issue.
RFID tags are more robust and reliable than barcodes. However, it is worth noting that they generally cost more.
In addition, bulk quantities of low-value items are often identified with a single RFID tag. In a busy shipping area, pallets of goods with RFID tags can be passing readers in many directions at the same time. i.e. goods being loaded or unloaded, and goods being transported to and from other storage locations.
The inventory system must be able to distinguish between all of these cases and accurately identify the tags that it should be reading. It must also ignore any other tags in the vicinity, including the stray tag that has become stuck to the forklift that is transporting the goods.
Another limitation of RFID tags is that they need to be within a few metres of the reader to be read. RFID warehousing systems are still reliant upon the operator placing the items in the location they were directed to and not moving an item to create space for another item. Furthermore, installing enough read heads to cover every location in a warehouse would normally be impractical.
RTLS
Real-time location systems (RTLS), in simplistic terms, use beacons in fixed locations within the warehouse or factory. These are used to triangulate the position of the receiver, in a similar way to GPS
navigation in cars and mobile phones. (GPS can be used to track goods in real time and is often the choice for use outside and during transport between factories.)
Inside factories and warehouses, RTLS typically uses either UWB (ultra-wideband) radio or BLE (Bluetooth low energy) as both are low power, have a relatively short transmission range of 30-200m, are resistant to interference, and are highly accurate, typically 50cm to 90cm.
RTLS would seem like the perfect solution to the warehousing problem. Put a ‘tag’ on every item and you can find its location, wherever it is, in real time.
Unfortunately, the RTLS equivalent of a tag is often more expensive than the item it would be attached to and requires a battery. So, typically, RTLS is only used to track high-value assets, vehicles and people.
A hybrid solution
However, if you are an expert in these technologies like Turck Vilant, you have the skills required to combine these technologies to create an accurate and reliable warehousing solution. This can integrate seamlessly with a company’s ERP (enterprise resource planning) and WMS (warehouse management system) to automate the tracking and tracing of goods in real time.
The principle is quite simple, but the execution requires expertise.
The Turck Vilant system tracks the position of the forklift trucks and other transport devices using RTLS. This is combined with the height data from the position of the forks and an RFID reader mounted on the truck to inventory the pallet. This
combined data allows the system to know exactly where any pallet has been placed and what is on that pallet.
While other systems fail due to unauthorised movement of goods, any time that a pallet is lifted or moved with the Turck Vilant system, it automatically tracks the new location in real time.
The Turck Vilant system is already being trailed by several industries. For example, a large company at Heathrow Airport is employing the technology to keep track of all UK exports, significantly enhancing the traceability of products being delivered around the world.
Meanwhile, in the medical industry, track and trace is a legal requirement. Nonetheless, hospitals and trusts lose thousands of pounds each year on something as simple and preventable as missing wheelchairs. This unique solution would help to tackle this problem by providing a complete, real-time stock inventory at the push of a button.
The technology could also be used for patient and consultant tracking, drug administration (ensuring the right medication is being delivered at the right dosage, to the right person), and blood transfusions (tracking the life cycle from the donor right through to the recipient).
Now that several Scandinavian healthcare companies have already adopted this next-generation technology, Turck Banner and Turck Vilant plan to team up with a digital health company to roll it out across the UK.
There will always be a balance between single item costs and the cost of methods available to track them. This is why Turck Banner has experts dedicated to track and trace who can not only give advice on the most cost-effective solutions, but who aim to push the boundaries of technology and innovation to achieve better solutions.