RTLS systems for production and manufacturing facilities

RTLS systems for production and manufacturing facilities should primarily include locating solutions that enable the precise location, inventory and tracking of equipment, goods and parts carriers and movable inventory. Indoor navigation is also often valuable in confusing locations, especially when external forces have to carry out work on the factory area.

Asset tracking is a key technology on the way to internal process optimization. In addition to reliability and precision, it is equally important in industrial applications that the position data can be integrated into existing inventory management systems. Our solutions therefore communicate via the MQTT message protocol, the de facto M2M standard for transmitting sensor information, and enable services based on real-time location data. Thanks to a standard JSON/REST Push/Pull API, all generated status and location data can be directly integrated into an existing CRM or ERP system.

Locating solutions for production facilities and manufacturing plants

Basically, three different asset tracking approaches can be distinguished, which come into their own individually and in parallel in the areas of industrial production and logistics/warehousing. A decision for an RTLS system should be made depending on the tracking requirements. This concerns both the choice of technology and the choice of positioning method. Depending on the positioning method, the choice of hardware must be made. The involvement of Favendo experts at the earliest possible stage of the project is therefore always in the interest of the customer.

Requirements for RTLS systems for production and manufacturing facilities

A distinction can be made between Presence, Proximity and Positioning based on the positioning accuracy:

• „Presence” only answers the question whether an object to be tracked is “there”, i.e. in the building. This is why the term “building level” is also used analogously.
• „Proximity” answers the question whether an object to be tracked is located in a certain zone within the building, therefore this tracking takes place at “zone level”.
• „Positioning” means an exact and constant location within the building. With this type of tracking, the movements of an asset within the building can also be tracked.

Advantages of Bluetooth Positioning

As a technological basis for RTLS systems for production and manufacturing facilities, Bluetooth Low Energy is suitable for all three requirement levels. Bluetooth operates at a frequency between 2.400 and 2.4835 GHz, the transmission power is far below the power flow limit of 10 W/m² and does not collide with even the strictest industrial safety conditions. As a short-range radio technology, Bluetooth is also extremely reliable. Frequency hopping reliably eliminates connection interference, as a disturbed connection is automatically replaced by a redundant connection. The hardware for the asset tags required for each tracking is extremely robust with very low energy consumption.

RSSI and AoA as methods for indoor positioning

While Bluetooth is the technological basis for asset tracking, RSSI (also called Beaconing) and AoA are two different methods of calculating the position of an asset. The methods allow different positioning accuracies. With the AoA method, localisation in the sub-metre range is possible, which also makes it possible to precisely locate small assets and to clearly identify assets stored close to each other. RSSI enables positioning between one and three meters, which can already cover many tracking requirements.

Basic principles of interior positioning in production facilities and workshops

RSSI (Received Signal Strength Indicator) describes a positioning with distance measurement according to signal strength and is also called Lateration, the effect of the decrease in signal strength used here is called Attenuation. If three signal transmitters are involved, it is called trilateration, if the number of signal transmitters is even higher, it is called multi-lateration.

Another method for determining a position is triangulation. In contrast to lateration, triangulation uses not only the distances to the signal generators but also the angles to determine the position of an object. For a two-dimensional identification of a position, two angles and one length are required. Angle – technically “angle of incidence” (AoA) – refers to the angle at which the signal strikes the receiver. The angle is measured by the delay of the signal (“Time of Flight” TOF). TOF measures the time taken for a signal to travel the distance between an object and the reference point, the known position of a transmitter.

AoA Asset Tracking in practice

AoA Asset Tracking enables the fast and reliable location of tools, medical devices and production equipment as well as small parts. At the same time, AoA Tracking also allows for the secure identification of closely spaced assets, so that large parts can be tracked reliably and precisely in tight spaces.

+ centimetre accurate tracking

+ Tracking assets of any size that are close together

For example, an aircraft engine manufacturer wants to identify and track the position of its unfinished engines in its workshop. Although the engines are very large, they cannot be tracked reliably using an RSSI-based method because the positioning is too inaccurate to identify the large objects stored next to each other. AoA Asset Tracking is sufficiently accurate to be able to distinguish the objects even in confined spaces and reliably identify the required workpiece.

For personnel working alone, high-precision tracking is a special safety factor, especially in critical situations in confusing environments. For example, when a single worker has an accident in a petrochemical plant. In emergencies, help can be sent directly to the person and not just to the appropriate section. The Wearable is an extremely reliable Bluetooth transmitter.

Favendo customers and partners can choose between RSSI or AoA or a custom-fit hybrid solution that ideally combines the strengths of both systems, depending on the application and requirements. For customers, Favendo remains the only contact partner with its proven installation and roll-out service. The set-up costs for the infrastructure are relatively higher when using AoA Locators due to the more complex planning and installation process, but still remain far below the costs of a UWB system. For AoA Asset Tracking we use the proven Quuppa hardware.

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