Automatic identification in logistics using radio frequency technology provides a huge leap in operational efficiency, speed of work, level of control. The theoretical basis of the solutions is widely described on many websites dedicated to RFID in logistics.
At RFID.zone, we decided to introduce the practical aspects of the various elements of logistics processes and the place that RFID in logistics can play. The sample scenarios presented below are just a slice of the broad possibilities that automatic identification can play in logistics systems. Given the potential large number of tagged objects and the rapid return on investment, we will focus on RFID in the warehouse.
In logistics, everyone is always in a hurry. Efficient unloading preparation allows drivers to work efficiently.
The RFID system - a long-range parking system - in the form of an RFID reader with a built-in antenna identifies the car on the basis of an RFID tag affixed to the windshield.
The data goes to the system, which back displays on the information board the number of the gate under which the car is to be placed. If there is a need to wait, P - parking is displayed.
The car backs up to the ramp. The RFID tag placed on the car door is read by one of the antennas of the unloading ramp. Confirmation of a correctly performed operation follows, along with a green light signaling.
The vehicle's cargo consists of pallets with goods. Each pallet with goods is tagged with a logistics label with an embedded RFID tag. The RFID tag uniquely identifies the pallet. An RFID gate is installed in the light of the unloading gate, which reads the pallet numbers by radio, automatically, and transmits this information to the master system. Only a few pallets are unloaded per minute, and it is usually known which side the label is placed on. Such a system will be handled by an RFID gateway built with one or two antennas. The antennas can be located on one side of the gate or above it.
In addition, the gate can simultaneously identify employees and, for example, forklifts involved in unloading. It is enough if the employees have UHF RFID cards with them and the forklifts are tagged with RFID tags.
In this area of logistics, thanks to radio-frequency identification we get information about, among other things:
When using tagged or RFID-tagged pallets themselves (not the cargo) whether wooden or plastic, they too are identified. This allows for accurate recording of pallet turnover. For the described scenario, deselecting pallets entering the warehouse in the system.
A forklift equipped with an RFID reader and antennas identifies each RFID-tagged pallet it takes from the goods receiving area. No barcode scanner is needed. With radio frequency identification technology, everything happens automatically. Putting a pallet on a rack in a high-bay warehouse, where the pallet space is also marked with a tag, is immediately recorded in the system. No pallet with goods is lost. Pallet racking processes can speed up to 20%, and the number of "lost" pallets drops to zero.
Similar functionality can be achieved when pallets are put down directly on the floor.
RFID tags embedded in the floor designate the exact locations or zones where the pallets are put away.
The solution with RFID-tagged locations and automatic registration of the storage area will work well both in densely built-up warehouse space and in open yards of several or several thousand square meters.
GPS systems cannot cope with accurately determining the position of a forklift in an enclosed warehouse space. Radio-frequency identification using UHF RFID will handle the task brilliantly. Accurate determination of the forklift's position can be done in two different ways.
If the cart is equipped with an RFID reader, its antennas can read location tags. That is, tags placed on walls, rack structures, in the floor, etc. The fixed position of the RFID tag is stored in a database, in the software. A cart passing by the tag reads it and records the position. This way of implementation makes it possible to supervise the position of the cart even with an accuracy of several centimeters.
Let's reverse the configuration, i.e. let's place the RFID reader, or rather its antennas, in specific positions of the warehouse, and let's tag the forklift with RFID tags. Then the passing cart will be automatically identified and the data will go into the system.
The known position of the cart can be used, for example:
Identification of stored pallets tagged with RFID tags, and thus their quantitative control, can be carried out in several ways:
Using a handheld UHF RFID terminal. Passing between pallets with the readout running, we scan the pallets without making eye contact with the label. The speed of scanning mainly determines the speed at which an employee moves through the warehouse. For example, from one of our actual deployments, a three-person team equipped with RFID terminals inventoried a warehouse with 6,000 pallets in less than 1.5 hours
Using an RFID reader mounted on a forklift. Identification is even faster due to higher radio power (compared to a hand-held terminal), more antennas, additionally directed simultaneously to both sides of the aisle between racks, and increased speed of movement. The aforementioned number of pallets can be inventoried in less than 15 minutes.
A system of RFID antennas permanently deployed in the warehouse, such as over pallet racks and along alleys, will allow real-time inventory. Depending on the method of implementation, these can be automatic identification systems providing data in seconds or minutes. The entire operation is performed without the involvement of employees.
All the aforementioned systems also provide information on the location of the pallet. The first two on the basis of RFID tagged locations. The location tags are read at the same time as the pallets. The third system described - provides the location based on knowledge of where the RFID antenna doing the reading is installed.