A real time locating system (RTLS) is a proven concept throughout many different industries. Typical operational areas for RTLS include:
- following a product through the assembly line (in a conveyor or non-conveyor belt system)
- distributing automated jobs for lifting machines based on the identification of an object
- identifying personnel and granting access to restricted zones
- locating mobile equipment in a hospital
Different scenarios will determine the technology and the set-up of the RTLS. Furthermore, not all technologies are suited to specific environments. For instance, sensitive equipment in hospitals is lifesaving but may be disturbed by a particular type of RTLS. As the range of signal and its strength are essential parameters of a solution, every project must be tested to understand the challenge better.
Real-time locating solutions may even consist of various technologies used simultaneously, e.g. RFID, UWD and NFC, combined in one system to perform different tasks. Therefore, it is crucial to choose correctly to avoid wrong design decisions already at the early stages. A proper methodology for RTLS design consists of such steps as modelling, requirements specification, and verification into a single process.
An RTLS solution consists of three main components: a tag or transponder, a receiver (a reader), and a software application that calculates the positioning. In the end, the actual scenario will define the ideal RTLS and the total amount of components.
A tag uniquely identifies an item or person. The tag can be mounted on the object or attached (imagine a lanyard for a person). A (passive) tag receives a signal from a receiver and answers back with its unique ID (your debit card when paying ‚without contact ‘). Still, it can also send the initial signal if it has its internal power source, like a battery. This is called an active tag, for instance, used in hospitals for mobile instruments or at big parking lots for parked cars.
A receiver is a middleman in an RTLS. The receiver’s task is to forward the data – including the ID of the object or person, timestamp, and distance – to back-end host servers. Receivers are typically sensors, access points, readers and so on.
There are countless examples of applying RTLS for increased productivity. Thinking of quality management and documentation, every single step of a production process can be automatically recorded and used later for proper quality assurance. Insufficient data collection due to manual documentation is a thing of the past, impacting the quality of goods and how management decisions are made.
