Nicola Accialini
4 min readApr 6, 2022

RTLS: Real Time Locating Systems to enable digital twins

RTLS, or Real Time Locating Systems, are an essential technology for Smart Factories.

How many of you spent lots of time searching for items, assets, parcels, tools, fixture around your facility, simply because they were not where they were supposed to be?

If you have worked for complex organizations, I am sure it has happened several times. It happened to me as well when I worked as Manufacturing Engineer for aerospace organisations, and it doesn’t matter how organized your company is. Logistic Complexity is simply difficult to manage.

Manufacturing environments are becoming more difficult to manage than ever for several reasons:

  • Pull Systems are more efficient, but imply a high turnover of assets
  • Reconfigurable Manufacturing Systems enable higher competitiveness; however, production lines must be reconfigured more often, with a lot items coming in and out
  • Parts Traceability is becoming a fundamental aspect in improving logistics efficiency; as lean manufacturing states “make the value flow smoothly”

In this sense, RTLS are becoming an essential tool for all manufacturing organizations. With RTLS, the more complex the system, the better.

Moreover, RTLS are the perfect solution to implement a digital twin of your logistic system. Indeed, RTLS enable the localization of physical assets in real time.

What is a RTLS?

Real-Time Locating Systems (RTLS) are used to identify and track the location of objects or people in real time, usually within a building or other contained area. Wireless RTLS tags are attached to objects or worn by people, and in most RTLS, fixed reference points receive wireless signals from tags to determine their location. Examples of real-time locating systems include tracking semi-finished products through an assembly line, or locating pallets in a warehouse.

How does it work?

The principle on which a RTLS is based is not dissimilar from the GPS. Instead of satellites, fixed detectors (or reference points) are located indoors, whereas tags (or asset beacons) are attached to mobile items or whatever is to be tracked: a pallet in the warehouse, a fixture in the maintenance & repair shop, a semi-finished part in the assembly line. Position is estimated using one or more locating algorithms, such as trilateration, multilateration, or triangulation.

The more RTLS reference points are installed, the better the location accuracy, until the technology limitations are reached. As a rule of thumb, the accuracy range is between 10–20 cm to 1–2 m.

In most cases the reference points are stand-alone and are powered by lithium batteries, therefore there are no constraints with the infrastructure.

Once the RTLS is implemented, how can we find the asset? Simply by using your smart device (i.e., smartphone, tablet, laptop): it will display your position and the target position on a map. Wearable devices, such as smart glasses, can be also used. In this case the main benefit is the implementation of a hands-free solution. Simple, faster and engaging!

The communication technology plays a fundamental role as well. Different solutions can be used, the most common of which are probably the followings:

Some companies offer the possibility of integrating the GPS into the beacon, therefore making it possible to track your items indoors AND outdoors. This can be particularly useful in case of a complex supply chain, in which the process involves several steps among different suppliers. However, a less expensive option would be to embed a detector at your supplier location.

To summarize, there are three main factors to be considered in the implementation of a RTLS:

  • Capillarity
  • Communication Technology
  • Locating Algorithm

Main benefits

As you have probably already understood, there are several reasons to implement a RTLS in your facilities. Some of them are:

  • Higher efficiency due to time waste reduction caused by searching for items, and owing to better production flow, as it is easy to visualize, and therefore optimize the real path of each item
  • Cost effectiveness: the price to pay is very little compared to the benefits you get, i.e., short Return of Investment
  • Quality: if a maximum time is allowed between different operations, like in Heat Treatments or in CFRP production, you can automatically track the time
  • Safety: RTLS solutions can be used to trace proximity between people, which is now an essential requirement for Covid-19 prevention
  • Security, such as an alert if an item leaves the facility unplanned

Where to start?

Technology is evolving at a very fast pace and the market is offering several solutions to make our facilities smarter. If you are dealing with high complexity in your shop, RTLS are definitely a smart solution to be adopted.

Once the need for such a solution has been acknowledge, the next step is to evaluate the accuracy required: 30 cm or 1m? Then, the capillarity and the communication technology can be defined. Software integration is also an important element: how the solution can be embedded in your IT infrastructure? Finally, the system can be sized and the budget estimated.

Accialini Training & Consulting is able to support you to identify and implement the best technology based on your specific requirements (i.e., accuracy and budget). Have a look at our pilot projects!

For more info, contact us to discuss more details.

Stay tuned.

Nicola Accialini

Engineer, consultant, digital entrepreneur and traveller, not necessarily in this order | Agile and Additive Addicted |