Key takeaways
- Many factory decisions require repeatable sub-50 cm positioning;
- UWB RTLS provides the accuracy and robustness to move from averages to per-unit truth—unlocking precise costing, safer automation and faster quality containment.
- Eliko’s UWB RTLS with AP-TWR protocol increases data density and resilience, making continuous, item-level tracking practical in metal-heavy halls—exactly what Krah Pipes used to quantify and improve their process.
Precise (≤50 cm) indoor positioning is now a standard tool for improving transparency, efficiency and profitability in smart manufacturing. Ultra-Wideband (UWB) real-time location systems (RTLS) deliver reliable decimeter-level accuracy even in metal-heavy environments, enabling item-level tracking, automated process triggers and accurate, per-product costing. This post outlines our main industrial use cases and why UWB technology is uniquely suited to these challenges.
UWB RTLS in brief: real-world decimeter-level accuracy in factories
Ultra-Wideband uses very short, wide-band radio pulses and measures either time-of-flight (ToF) or time-difference-of arrival (TDoA) of the radio signal. UWB delivers centimetre-level distances and resilience against reflections. These measured distances in centimetres result in a ~10–30 cm indoor positioning accuracy for well-designed UWB systems.
Why this matters in factories: reflections from machinery, racks and cranes will corrupt distance estimates for narrow-band technologies like BLE. UWB’s nanosecond-scale time resolution separates direct paths from reflections, maintaining consistent coordinates for moving assets, tools and WIP.
Eliko is a company specializing in UWB RTLS with an in-house built hardware, software and a hybrid protocol that ensures that our system can flexibly track any object in heavy industrial environments. The unique tracking protocol was developed in cooperation with universities and combines the key aspects of ToF and TDoA positioning into a robust workhorse RTLS solution.
Case example — Krah Pipes: from approximations to per-pipe, real-time costing with UWB
The production reality
Krah Pipes manufacture large-diameter thermoplastic pipes on full-metal mandrels (drums). These mandrels are sizeable, dense and highly reflective to RF—effectively impenetrable to radio from the opposite side. Every previous attempt to track the mandrels in real-time failed because of a high level of false data, including cameras and industrial-grade RFID.
From approximations to per-pipe truth
Before RTLS, Krah estimated material, gas and energy consumption per order. The result: occasional shortages, overproduction, and uncertainty in margins.
Krah Pipes CEO was initially sceptical about radio-based tracking since previous experience to monitor production in real time had failed. However, after a successful demo, the solution was scaled to the entire production area. The IP67 tags require little maintenance, endure the 100 degrees C temperatures on the mandrel.
After installation, every pipe’s movement is now tracked continuously, and production steps start/stop automatically when a tagged tool or pipe enters the defined zone. The MES binds actual raw materials, kWh and gas to each individual pipe, giving unit-level costs and a precise production station timeline data for quality analysis.
Business outcomes
- Per-pipe costing: every kilogram of raw material, every kWh and cubic metre of gas is allocated to the actual pipe that consumed it, not an average.
- Automated flow: location events trigger recipe start/stop with no operator taps.
- Quality containment: when an issue is found, the team jumps directly to the time/position where the deviation arose and corrects the flow.
The anchor geometry challenge—and how we solved it
The Krah Pipes production hall layout forced Eliko to use a one-sided anchor deployment: anchors could be mounted only along one wall; placing infrastructure behind the mandrels were made of solid metal which blocks UWB (and all other RF) completely. Metal-rich, NLoS-heavy environments are precisely where UWB’s wide bandwidth and ToF ranging excel at separating direct from reflected paths, but the geometry here was still unusually constrained.
A standard UWB TDoA system typically needs synchronised anchors with favourable geometry around the working area. In one-sided layouts, geometric dilution of precision rises and lack of multi-anchor line-of-sight can degrade accuracy. Moreover, TDoA infrastructures depend on tight time synchronisation across anchors (usually via wiring or complex wireless sync), and even small sync errors add position bias.
Eliko’s AP-TWR (Active-Passive-Two-Way Ranging) protocol sidesteps these constraints. By combining passive listening at anchors with active, two-way tag↔anchor exchanges, the system computes reliable ranges without relying on multi-anchor simultaneous reception or hard-wired clocking across the hall. In Krah’s one-sided deployment, AP-TWR delivered repeatable ~30 cm accuracy despite the mandrels fully shadowing radios from the opposite side. The protocol’s high data density (from multiple micro-exchanges per positioning instance) also sharpened trajectories, enabling precise, automatic step detection at workstations.
Why this works technically: AP-TWR measures ToF between a tag and only some anchors; it is independent of inter-anchor clock synchronisation and can operate robustly with fewer, asymmetrically placed anchors. TDoA, by contrast, needs the tag to be inside an area surrounded by anchors and for those anchors to be tightly synchronised—conditions that were the Krah Pipes use case definitely violated.
Why precise positioning changes factory economics
Precise UWB RTLS shifts decisions from averages to actuals:
- Per-product costing & margin control: track the precise dwell time at each station, actual transfer times and rework loops per unit; allocate material, energy and gas to the individual product—not the batch.
- Automated process control: trigger PLCs/MES when a specific tool or WIP enters a defined zone; start and stop recipes automatically with a location event rather than manual input.
- Bottleneck detection and flow redesign: high-rate trajectories expose micro-stops and back-and-forth motion; heatmaps guide layout changes and kanban sizing.
- Quality traceability: automatically bind torque curves, weld parameters or curing profiles acquired from other systems to the exact product position and time, improving compliance and speeding investigations.
When <50 cm accuracy is essential: high-value UWB use cases
- Work-cell process and cycle monitoring: determine how long each product spends in a specific workzone. Zones are often right next to each other, so that accuracy needs to be precise and robust.
- Automatic warehouse management – By bringing together real-time tracking and identification you can track large numbers of WIP and material movements automatically by only directly tracking the carriers (cranes or forklifts).
- Robot and AGV/AMR traffic management: manage the entire AGV/AMR fleet in one system. Accurate RTLS is a backbone of any such system.
- Crane and hoist or forklift positioning for safety: enforce real-time slow-speed or no-go zones within 0.5 m radius of a crane hoist; log precise positions for near-miss analytics.
- Assembly sequencing & kitting: prevent line misses by confirming the exact kit bin chosen when bins are closely spaced.
- WIP genealogy for quality and efficiency analysis: capture and verify the exact sequence of processes in real-time, send alerts when process times become to long or workstations too crowded.
Across these scenarios, sub-50 cm accuracy UWB RTLS avoids false positives/negatives that undermine automation and costing.
Why Eliko UWB RTLS is built for production floors
Eliko’s system combines UWB accuracy with a protocol engineered for data density and reliability:
- AP-TWR protocol (Anchor Passive + Two-Way Ranging): Eliko blends passive listening from anchors with active tag-anchor exchanges. The result is up to 8× more data points per positioning instance, improving trajectory smoothness and event timing.
- Consistent coordinates in metal-heavy halls: UWB’s wide bandwidth and ToF ranging maintains stable positions despite reflections; anchors tolerate non-line-of-sight paths better than narrow-band systems.
- Industrial hardware: IP67 tags and rugged anchors designed for magnets or bolted mounts; timing-synchronised infrastructure for high update rates and low latency.
For Krah Pipes, this has meant continuous pipe-level visibility, automatic cycle timestamps, exact resource attribution and faster quality containment—moving from “best guesses” to hard facts.
Eliko data can be integrated with various MES and ERP software. One option is the software platform offered by Flowcate Location Data Software, which makes it easy to connect different positioning technologies and create applications based on them.
Learn more about the Eliko RTLS or UWB technology or Get in touch to see how your operations can benefit from better visibility of assets, people and materials.
