Representative Use Cases of Indoor Positioning in Warehouse Operations and LRTK Deployment Examples

Table of Contents

• The Need for Indoor Positioning and Background (Challenges in Warehouse Operations)

• Representative Use Cases in Warehouses - Accurate item/inventory location identification and improved picking efficiency - Surveying and staking out positions when moving shelves or changing layouts - Visualizing worker/vehicle flows for operational improvement and safety management - Use in equipment maintenance inspections (records with location information)

• Actual Deployment Examples (Use by Municipalities and Logistics Warehouses)

• Comparison of Indoor Positioning Technologies and Selection Points

• Workflow for Simple Surveying/Indoor Positioning Using LRTK (Ease and Accuracy)

• Future Prospects and Points to Consider for Deployment

• Summary: Take the First Step Toward Field Improvement with LRTK

• FAQ (Frequently Asked Questions and Answers)

The Need for Indoor Positioning and Background (Challenges in Warehouse Operations)

In large indoor spaces such as logistics warehouses and factories, the positional information of "where things and people are" directly affects operational efficiency and safety. Accurate awareness of inventory placement, equipment layout, and the movement paths of workers and forklifts is required in every situation. Traditionally, staff often relied on experience and intuition to find items or measured and placed equipment using paper drawings and tape measures—practices that caused inefficiencies. By using digital technologies to visualize location on site, wasteful movement can be reduced and productivity improved.

In particular, demand has grown recently for measuring positions inside warehouses with centimeter-level accuracy. Conventional methods that can only achieve meter-level errors made it difficult to perform precise tasks and fine layout adjustments, but if indoor positioning with cm level accuracy (half-inch accuracy) becomes possible, such tasks become feasible. For example, shelves and equipment can be aligned without even a few centimeters of deviation, or the travel paths of work vehicles can be analyzed in detail to derive optimization measures. High-precision location information is becoming an indispensable element in warehouse optimization and on-site Kaizen.

Representative Use Cases in Warehouses

How exactly can indoor positioning help in warehouses? Below are representative use cases in warehouse operations.

Accurate item/inventory location identification and improved picking efficiency

In vast warehouses, accurately knowing storage locations is the key to efficient picking. If shelf and product positions are pre-registered in an indoor positioning system as 3D coordinates, workers can move while checking their current location and the target product’s position on a device map or AR screen. For example, following navigation displayed on a smartphone or tablet allows even new staff to reach the target product without getting lost. Time spent searching for items during picking is reduced, and unnecessary movement and picking errors are greatly reduced. As a result, per-person picking time is shortened and labor costs and lead times are reduced.

Surveying and staking out positions when moving shelves or changing layouts

Layout changes and additions/movements of racks occur regularly in warehouses. In such cases, accurate preliminary position surveying is important. For example, when installing a new large rack, floor staking (marking) is required to install it according to the plan on drawings. Using indoor positioning, installation points on the floor can be measured to centimeter precision. By marking while comparing planned values and on-site survey values, shelves and equipment can be installed without even a deviation of a few centimeters (a few 0.4 in). This prevents rework such as reinstallation or position correction and reduces backwork. Keeping accurate placement data for equipment and shelves after a layout change also helps with future renovation or expansion planning.

Visualizing workflows for operational improvement and safety management

Recording and visualizing the movement paths of people and vehicles (e.g., forklifts) inside a warehouse is another useful use case for indoor positioning. By having workers carry smartphones with positioning enabled and walk for a set period, continuous logs of their movement paths can be obtained. Analyzing trajectory data with centimeter precision (cm level accuracy (half-inch accuracy)) can reveal areas with excessive back-and-forth movement, frequent stops, or congestion-prone zones. Based on this information, revising layouts or movement rules can produce clear effectiveness measurements such as “wasteful movement reduced by X%.” In practice, optimizing picking area divisions and shelf placement has led to examples where a worker’s walking distance was reduced by 50%. Movement data also aids safety management: by accurately understanding the passage ranges of people and forklifts and improving zones where dangerous crossing occurs, accident risk can be reduced.

Use in equipment maintenance inspections (records with location information)

Indoor positioning is also powerful for equipment and facility inspections within warehouses. When inspectors record discovered defects or anomalies, recording them with precise location information makes subsequent responses markedly smoother. For example, using a positioning tool like LRTK to take photos at inspection sites automatically tags the photo files with cm level accuracy (half-inch accuracy) coordinates and camera orientation (bearing). Plotting those photos on a cloud map or 3D model makes it obvious “which part of which shelf is damaged” and “which locations should be prioritized for the next inspection.” Compared to the conventional method of marking “around here” on paper drawings by hand, the accuracy of records and speed of sharing are dramatically improved. As a digital transformation (DX) for maintenance and inspection, this approach is attracting attention as a way to accurately digitize and share on-site knowledge.

Actual Deployment Examples (Use by Municipalities and Logistics Warehouses)

Here are some real-world examples demonstrating the effectiveness of indoor positioning, including deployments by municipalities and logistics warehouses.

• Municipal use example (Fukui City case): Municipalities have begun adopting smartphone surveying devices for on-site work. Indoor positioning proved powerful in disaster response. In Fukui City, LRTK was trial-introduced early at the 2023 large-scale heavy rain disaster recovery sites and used to measure damage. Previously there was a time lag in calling surveyors after damage was discovered, but staff themselves could immediately perform precise measurements of damage on site, reducing back-and-forth between the field and the municipal office, improving response speed, and reducing costs. Even with limited personnel, damage could be efficiently recorded, and recovery planning was accelerated. The ability to conduct detailed local surveys using only a smartphone has been well received, and such tools are gaining attention in municipal disaster prevention. In another case, LRTK was used for on-site surveying after an earthquake in the Noto region. Even in damaged areas with unstable communications infrastructure, receiving augmentation signals (CLAS) from Japan’s Quasi-Zenith Satellite System “Michibiki” directly allowed high-precision positioning and detailed records of ground displacement. These examples show that enabling field teams to immediately acquire and share precise location data produces significant effects in infrastructure inspection and disaster response.

• Logistics warehouse use example: In the private logistics sector, demonstrations have shown efficiency improvements using indoor positioning. In one major logistics company’s warehouse, an indoor positioning system using ultra-wideband (UWB) tracked the entire routes of picking carts in an experiment. Analysis of collected movement data and optimization of shelf placement and assigned areas resulted in reported worker walking time reductions of 50%. Per-pick processing time was also shortened, greatly improving work efficiency. These cases demonstrate that high-precision location data can significantly reduce wasteful movements and improve layouts in warehouses. However, conventional UWB systems require installation and calibration of dedicated anchor devices, which involves cost and effort. For that reason, there is growing interest in smartphone-integrated RTK positioning devices such as LRTK, which enable precise positioning more easily. LRTK, already widely used in construction and civil engineering, has begun to be adopted not only by national ministries, municipalities, and major construction firms but also by smaller contractors. In logistics warehouses, LRTK is expected to spread as a positioning solution with a low initial introduction hurdle.

Comparison of Indoor Positioning Technologies and Selection Points

Various methods exist to realize indoor positioning, each with advantages and disadvantages. When introducing a system, it is important to select the optimal method based on your warehouse environment and objectives. Below is a comparison of representative indoor positioning technologies and selection points.

• Positioning using BLE beacons or Wi‑Fi: This method estimates position from signal strength received by a device from multiple radio transmitters (BLE beacons or Wi‑Fi access points) installed in the facility. It can be used with smartphones without dedicated tags and is relatively low-cost to start, but accuracy is often on the order of several meters and unsuitable for high-precision applications. Errors due to radio reflection and shielding are large, and accuracy tends to be unstable in warehouses with many shelves and cargo.

• Positioning using UWB (ultra-wideband): By using UWB signals with nanosecond-level timing, accuracies of tens of centimeters and in some cases around 10 cm can be achieved. Multiple fixed anchor antennas are installed on the ceiling or walls, and position is calculated based on differences in distance to them. Accuracy is excellent, but installation and maintenance of dedicated hardware incur costs, making initial introduction more burdensome. Layout changes may also require reconsideration and readjustment of antenna placement.

• Ultrasonic/acoustic positioning: This method places sound transmitters on the ceiling and determines position from differences in sound arrival times. Because it uses sound rather than radio, positioning can work even through some obstructions, and some systems can obtain 3D positions. While theoretically capable of high precision, it still requires dedicated infrastructure installation and pre-calibration. Practical operational issues include the effort to place speakers and microphones throughout the warehouse and stable operation in noisy environments.

• Self-localization using cameras/LiDAR: This technique estimates self-position from camera images or LiDAR data carried by vehicles or workers by recognizing surrounding landmarks and geometry. Because it relies on vision, it is often operated after creating an environmental map of the warehouse in advance or by installing markers like QR codes or reflectors. Using high-quality cameras or LiDAR improves accuracy, but equipment costs can be high and specialized knowledge for installation and maintenance is often required.

• PDR (Pedestrian Dead Reckoning): This method detects walking steps from accelerometers and gyros in a smartphone and integrates relative position from a known start point. Alone, it requires no advanced infrastructure and is relatively effective for short periods, but it has a fatal weakness of cumulative error (drift) over time. For long-distance movement, position progressively drifts, so it needs to be combined with some method of periodic position correction.

As shown above, conventional indoor positioning technologies generally require infrastructure installation or significant investment to achieve high precision, making it difficult to balance ease of use and accuracy. Many methods excel at obtaining X–Y floor coordinates (planar positions) but are weak at precise Z-axis (height) measurement. However, in warehouses information about height—such as which shelf tier an item is on or floor slopes and steps—is important. Therefore, when evaluating indoor positioning technologies, it is necessary to comprehensively assess required accuracy (both horizontal and vertical), installation cost, and operational ease.

Given these considerations, an approach gaining attention is applying RTK (Real-Time Kinematic) technology. RTK originally corrects satellite positioning (GPS etc.) errors to achieve centimeter-level accuracy and has been used in outdoor civil engineering surveying. Recently, receivers have become smaller and more affordable, and there is a trend to apply RTK to indoor positioning. RTK can potentially realize both ease of use and high accuracy in a different form from conventional infrastructure-dependent methods. A concrete example is the smartphone + RTK-compatible device solution such as LRTK.

Workflow for Simple Surveying/Indoor Positioning Using LRTK (Ease and Accuracy)

A new approach that addresses the above challenges is the small, high-precision positioning device that can be used with a smartphone: LRTK. Below, using LRTK as an example, we describe the specific workflow for simple surveying and indoor positioning in warehouses and discuss its ease and accuracy.

• Setup (Preparation): The only items needed for positioning are *the LRTK device itself* and a *compatible smartphone*. LRTK currently supports iOS devices such as iPhone and iPad. First install the dedicated LRTK app on the smartphone. Then attach the LRTK device to the smartphone (for iPhone, mount it in a dedicated case; on Android use the included attachment) and pair via Bluetooth. Turning on the device immediately starts GNSS positioning, and satellite reception status is displayed on the app. The device weighs only about 165 g and has a compact profile of about 1 cm thickness (about 0.4 in) with a built-in battery, so it does not interfere with work (it operates for up to 6 hours on a full charge). Heavy tripods or stationary equipment are unnecessary—this is truly a surveying instrument you can carry in your pocket.

• RTK positioning initialization: For accurate positioning, initialize high-precision RTK positioning before starting work. Specifically, start the app in a place with clear sky view such as outside the building, on the roof, or by a window, and wait for several tens of seconds to about a minute. GNSS will be stably acquired, RTK corrections will be received, and positioning accuracy will rapidly improve. When the app status shows a “Fix solution,” horizontal ±1–2 cm (±0.4–0.8 in) and vertical ±2–3 cm (±0.8–1.2 in) accuracy can be achieved. Initialization is automatic with no button operation required and completes in a short time if the sky is visible. Once this preparation is complete, you can proceed to indoor surveying.

• Point measurement indoors: Now measure the locations you want inside the warehouse. GPS signals are usually not receivable indoors, but the LRTK system leverages the smartphone’s sensors and AR technology. The smartphone’s camera, LiDAR, accelerometer, and gyro continuously track device movement in real time, so relative positions from the high-precision reference obtained outdoors are sequentially calculated. Simply put, while moving indoors the smartphone acts as a high-performance pedestrian navigation device and continuously supplements your movement. For example, even if you want to measure a shelf located deep inside the warehouse, if you perform RTK position calibration near the entrance, walking to the shelf while holding the smartphone will let you acquire the shelf’s accurate coordinates. When you reach the measurement point, tap the “Point Positioning” button on the app. The device is held still for a few seconds while positioning data is automatically averaged, and the high-precision latitude, longitude, and height of that point are recorded. Optionally enter a point name or memo and save. The convenience of obtaining centimeter-level coordinates with a single tap is a user-friendly experience not available with traditional surveying instruments.

• Additional features such as positioning photos and AR display: The LRTK app includes useful functions beyond single-point measurement. For example, switching to “Positioning Photo” mode records the photo along with the shooting location (high-precision coordinates) and camera orientation in one tap—very useful for inspection work. You can also place virtual markers on recorded points and display AR guidance on site. When staking out the position specified on a drawing, arrows and targets appear on the smartphone screen to guide the user. Even without surveying expertise, following AR guidance allows accurate staking work. Furthermore, using the iPhone’s built-in LiDAR and camera, simply walking around can capture high-precision 3D point cloud (scan) data. Scanning the warehouse generates a 3D model with georeferenced points, useful for recording layout before and after changes and for creating equipment inventories. The fact that many of these functions are completed with just a smartphone + LRTK device is a major advantage. There is no need to carry multiple specialized devices or operate a PC on site; measured data can be uploaded directly from the smartphone to the cloud for immediate sharing.

• Points for maintaining accuracy and re-correction: With LRTK indoor positioning, short-duration, short-distance movements maintain centimeter-level accuracy thanks to AR-based tracking. However, if GNSS is not observed at all for a long time, minor accumulated errors in the smartphone’s self-positioning may occur. For measuring across a very large facility, it is advisable to go outside or to a windowed area once in a while to reapply RTK correction. Fortunately initialization completes quickly, so occasional re-sets can maintain high accuracy during work. Actual verification confirmed that measuring around ten indoor points in succession resulted in point-to-point error variation within a standard deviation of 1–2 cm (0.4–0.8 in). Moreover, by measuring a single point multiple times and averaging, errors approaching less than about 1 cm (0.4 in) can be achieved. In other words, with appropriate operation, indoor positioning comparable to outdoor RTK can be obtained.

As described above, LRTK enables anyone to easily perform centimeter-level surveying without specialized surveying skills. Data acquired on site synchronizes automatically with the cloud and can be immediately reviewed from a company PC in 2D maps or 3D views. You can calculate distances and areas between measured coordinate points, compare with existing drawings, and perform such tasks in a browser. Sharing is smooth: simply send a URL from the cloud to colleagues or partners so they can view results without special software. Coordinate systems such as Japan’s plane rectangular coordinates are supported, ensuring compatibility with CAD drawings and GIS data.

Future Prospects and Points to Consider for Deployment

Indoor positioning and smartphone surveying technologies are changing how fieldwork is done. Surveying and staking-out used to be specialist tasks, but we are moving toward an era where on-site staff can quickly measure as needed. The fusion of high-precision GNSS and smartphones democratizes surveying, making the notion that “anyone can be a surveyor” increasingly realistic.

In warehouse operations, spread of indoor positioning will bring many benefits. Decisions on layout changes that previously stalled while waiting for survey reports can now be made immediately with accurate on-site data, dramatically increasing operational speed. This leads to shortened schedules and cost reductions, contributing to productivity. Cloud integration lets office staff instantly review and instruct based on on-site data, reducing travel time and enabling remote support. This shortens risky on-site work time and improves safety.

Looking ahead, implementation in AR glasses or helmets could allow hands-free high-precision navigation and data capture. Integration with 5G and AI image analysis could enable more real-time tracking and automated anomaly marking. While LRTK is currently used as a handheld device, it could eventually be mounted on AGVs or robotic forklifts for autonomous warehouse navigation. If robots can determine self-position with centimeter accuracy, advanced control such as maintaining precise distance from humans or millimeter-accurate approach to shelves for loading/unloading would be possible.

However, deploying these technologies requires consideration tailored to the site and operations. For example, if a warehouse has underground floors with no satellite signals, using LRTK there may require pre-measuring ground reference points outdoors and covering the area by relative positioning. When evaluating options, consider required coverage and accuracy, initial and running costs, ease of integration with existing systems (inventory management, WMS, etc.), and whether on-site staff can use the system without undue burden.

Fortunately, solutions like LRTK allow a small-scale start. You can pilot in a single department or site, verify effects, and scale up gradually. Gather feedback from on-site staff and reflect improvements in usability and workflow to discover the best use case for your company. National initiatives promoting DX and i-Construction in the construction industry are progressing, and high-precision location information is becoming indispensable in logistics as well. Consider benefits observed in other companies as references when evaluating adoption for your warehouses.

Summary: Take the First Step Toward Field Improvement with LRTK

This article covered the necessity of indoor positioning for warehouse equipment management and surveying, representative use cases, deployment examples, technology selection points, and LRTK-based solutions. Achieving centimeter-level indoor positioning enables improvements in inventory accuracy, faster layout changes, better work efficiency, and enhanced safety—bringing significant benefits to the field.

Simple surveying with LRTK directly addresses on-site problems such as “we need to measure but can’t” or “we’re troubled by position errors.” Intuitive smartphone-integrated operation, one-handed usability, and smooth information sharing via AR and cloud make precise positioning—once the domain of specialists—accessible to everyone. When high-precision location information permeates every corner of the site, daily operations themselves will be updated, raising overall field capability.

If your workplace faces challenges like “we want to know item locations more accurately” or “we want to streamline layout changes and inspection records,” consider smartphone surveying with LRTK. Its ease of getting started even for first-time users will likely make it a powerful ally for on-site improvement. Embrace the latest technology and take the next step for your warehouse operations.

FAQ (Frequently Asked Questions and Answers)

Q. What is needed to introduce indoor positioning using LRTK? A. The required equipment is only the LRTK device itself and a compatible smartphone (iPhone/iPad, etc.). First install the dedicated LRTK app (free) on the smartphone and connect the device via Bluetooth or Lightning. Before measuring, initialize RTK correction in a place with satellite reception such as outside or by a window. Thereafter, carry the smartphone inside the warehouse and press a button at any desired point to measure. No base station installation or prior calibration is needed, so you can start measuring as soon as preparation is complete.

Q. Is the positioning accuracy really at the centimeter level? Won’t accuracy degrade indoors? A. Yes—when properly operated, positioning can achieve errors consistently within a few centimeters. If you obtain an RTK Fix solution (cm level accuracy (half-inch accuracy)) outdoors in a clear view of the sky, entering the building immediately afterward will not cause a large drop in accuracy. The smartphone’s AR technology maintains high self-positioning accuracy for short durations and distances, allowing you to acquire coordinates indoors at roughly the centimeter level. However, if satellites are not captured at all for an extended period, error accumulation will occur, so for large floors it is advisable to re-correct at a place where satellites can be seen (entrance, window). In practical operation, inserting corrections as needed keeps indoor point results within a standard deviation of about 1–2 cm (0.4–0.8 in). Measuring a point multiple times and averaging can achieve less than about 1 cm (0.4 in) accuracy.

Q. How portable is the LRTK device? Are weight and battery life problematic? A. The LRTK device is very compact and lightweight, weighing about 165 g and having a thickness of about 1 cm (about 0.4 in). It fits in a pocket and is designed not to interfere with on-site work. It runs on an internal battery for about 6 hours on a full charge. Charging is via USB Type-C, and it can be used while powered by an external battery, so battery depletion is rarely a concern during long surveys. It can be handled one-handed with the smartphone, making it maneuverable for high-place work or ladder use.

Q. Can it be used where there is no communication? What happens in areas of a warehouse with no signal? A. Yes, it can be used without internet connection. The LRTK device supports Japan’s Quasi-Zenith Satellite “Michibiki” centimeter-class augmentation service (CLAS). This means that even outside mobile coverage, if the sky is visible, correction information for RTK can be received directly from the satellites. Therefore, in areas without network but with open sky—such as mountainous regions or locations near entrances of underground facilities—high-precision positioning is possible. For indoor positioning, if Michibiki signals can be captured at a window or rooftop without network, centimeter accuracy can be maintained without internet. However, in environments with no sky view at all, such as deep underground, satellite signals cannot reach and it becomes difficult. In such extreme cases, supplement with relative positioning from ground-measured reference points or by referencing existing drawings.

Q. How are survey data managed and shared? Can on-site measurements be used within the company? A. Positioning data acquired with the LRTK app can be effectively utilized by automatic cloud synchronization. Coordinates, photos, and scanned point cloud data can be uploaded to the cloud with one tap. Uploaded data is viewable on a dedicated web platform in 2D maps or 3D views. Measured points and photos are plotted on maps, and tools for measuring distance and area are provided. You can issue web-view URLs so colleagues or partners without specialized software can view the data, enabling smooth internal and external sharing. Data can be converted to Japan’s plane rectangular coordinate system (or other systems) and easily overlaid on CAD drawings or GIS data, allowing on-site measurements to be compared with design drawings or shared instantly with remote stakeholders.

Q. Is specialized knowledge required to operate or introduce the system? Can beginners with no surveying experience use it? A. No specialized qualifications are required—the system is designed to be intuitive. LRTK features a simple UI and automated processing so first-time users can operate it without confusion. Mounting the device is as simple as attaching it to a pole (monopod) and making it vertical; no complex adjustments are needed. The app shows current positioning mode (Fix/Float, etc.) and satellite count, so beginners can easily understand current accuracy. Comprehensive manuals and tutorials are available, and support desks provide follow-up if questions arise. In practice, on-site equipment managers and staff without surveying experience can handle LRTK surveying after a short briefing. No special qualifications or long-term training are needed; anyone can become proficient in a short time.