Centimeter-level accuracy (cm level accuracy (half-inch accuracy)) × Cloud Sharing × Smartphone-Integrated — The New Era of Surveying Opened by LRTK Phone

Table of Contents

• New possibilities brought by centimeter-level positioning

• Field-office collaboration enabled by cloud sharing

• Ease unique to smartphone-integrated devices

• Main functions LRTK Phone brings to the field

• Comparison with conventional surveying methods

• Conclusion: The new surveying era enabled by field DX

• FAQ

The era in which a smartphone can quickly transform into a high-precision surveying instrument has arrived. Until now, surveying generally required specialized equipment and skilled technicians. But today, a small device attached to a smartphone allows anyone to perform surveying with centimeter-class accuracy. A representative example is the LRTK Phone. Combining centimeter-level accuracy (cm level accuracy (half-inch accuracy)), cloud data sharing, and smartphone integration, the LRTK Phone is truly a device that opens a new era in surveying.

On construction and civil engineering sites in recent years, aging of skilled surveyors and labor shortages have become issues. Also, under the Ministry of Land, Infrastructure, Transport and Tourism’s initiative *i-Construction*, efficiency using ICT and utilization of 3D data are being required. Against this background, the arrival of the LRTK Phone is overturning the conventional view that “surveying requires large-scale equipment and multiple people.” In this article, using the keywords centimeter-level accuracy (cm level accuracy (half-inch accuracy)) × cloud sharing × smartphone-integrated, we explain in detail the benefits and use cases the LRTK Phone brings.

New possibilities brought by centimeter-level positioning

Traditional smartphone GPS typically has errors on the order of several meters (several ft), making it unsuitable for precise surveying. Enter RTK (real-time kinematic), a high-precision positioning technology. RTK combines correction information from a base station with the mobile receiver (terminal) to correct positioning errors in real time, achieving errors within a few centimeters (within a few in). The LRTK Phone is a revolutionary device that makes this RTK method easily usable with a smartphone.

With LRTK Phone, an ultra-compact GNSS receiver attached to the smartphone captures signals from multiple satellites and, by comparing them with reference station data obtained over the network, calculates highly accurate position coordinates. Normally, correction information (so-called GPS correction services) is received via the Internet, but you need not worry even at sites outside cellular coverage. It supports the centimeter-class augmentation service (CLAS) provided by Japan’s quasi-zenith satellite “Michibiki,” allowing correction data to be obtained via satellite and enabling centimeter-class positioning even in mountainous areas or disaster sites where mobile signals do not reach. This makes it possible to realize high-precision positioning that previously required expensive fixed equipment or setting up base stations with a pocket-sized device.

The benefits of centimeter-level accuracy are immeasurable. For example, tasks like formwork alignment and stake setting require that deviations of a few centimeters (a few in) not occur, as they can lead to serious errors. With LRTK Phone, you can simply place the terminal at the point you want to measure and press a button on your smartphone to record the latitude, longitude, and elevation of that point with high precision. Positioning results are automatically converted to Japan’s plane rectangular coordinate system and geoid height, eliminating the previously time-consuming coordinate conversion tasks. The acquisition of absolute coordinates, which used to rely on specialized surveying equipment and skilled personnel, becomes easy for anyone.

Field-office collaboration enabled by cloud sharing

Another major feature of LRTK Phone is the ability to upload acquired survey data to the cloud instantly. Coordinates of measured points and photos taken at the site are synced to the dedicated LRTK Cloud with a single tap from the smartphone app. On the cloud, the measured points are plotted on a map, and office PCs can view field data in real time via a web browser.

This cloud sharing dramatically speeds up information transfer between the field and the office. For example, field personnel can immediately share measured position data or point cloud data with remote designers or clients. Data include timestamps and notes, so it is possible to accurately understand what measurements were taken on site. Where information sharing used to be done via USB drives or paper drawings, with LRTK Phone the data are stored directly into the database from the field.

LRTK Cloud also includes a function to issue shared links. To share survey data with another company, simply select the data on the cloud and issue a shareable URL. Recipients can view the data on the web without logging in (passwords or expiration dates can be set if needed). Measurement results can also be downloaded in common formats such as CSV, DXF, and LAS, facilitating smooth import into CAD software or other point cloud processing tools. Open data sharing via the cloud enables all stakeholders to instantly share and utilize surveying results that previously had to be exchanged individually.

Ease unique to smartphone-integrated devices

The greatest strength of LRTK Phone is the ease of use that comes from integration with a smartphone. The receiver itself weighs only about a hundred-some grams and can be attached to a smartphone via a dedicated case or magnetic attachment. Its pocketable size means you can carry it on site and “take it out and measure whenever needed.” There is no need to carry a tripod like conventional surveying instruments, enabling agile work such as walking around the site while taking measurements.

Also, the intuitive operation via the smartphone app is beginner-friendly. To start positioning, simply launch the dedicated app and tap a few times. Without complicated settings or specialized knowledge, anyone can begin high-precision surveying by following the app’s guidance. Because you can operate while viewing maps and camera images on the smartphone’s large screen, the UI is overwhelmingly easier to understand compared to conventional surveying equipment. In practice, site managers and workers can each master the LRTK Phone, making operations like “one device per person” for surveying and recording realistic.

There are other benefits to smartphone integration. You can take advantage of abundant built-in smartphone features such as the smartphone’s camera, LiDAR sensor, and accelerometer. For example, with LRTK Phone you can automatically attach positioning information (the coordinates and orientation of the photo location) to photos taken with the smartphone camera. This dramatically simplifies later tasks of confirming the shooting location for each photo or compiling reports. Furthermore, by integrating with the LiDAR scanner on iPhone/iPad, you can perform 3D scans of nearby objects. Combining RTK-derived position information with point clouds obtained by the smartphone makes it possible to generate precise 3D point clouds with coordinates on the spot.

Main functions LRTK Phone brings to the field

LRTK Phone is more than a positioning device; it provides a variety of useful functions for fieldwork. Here are several of its main functions and uses.

• Single-point positioning and recording: Point the device at the desired location and tap a button on your smartphone to take a single measurement. The acquired coordinates are automatically saved and managed with point names, timestamps, and notes. Useful for measuring control points on survey plans and for as-built checks.

• Continuous positioning (track measurement): A function to continuously record positions at set intervals while moving. For example, for slope or road longitudinal surveys, simply walking will acquire track data. The obtained track can later be checked as cross-sections or imported into CAD drawings.

• 3D point cloud scanning: Use the smartphone camera and LiDAR to scan structures or terrain in front of you in a short time and convert them into 3D point clouds. Since LRTK Phone is constantly correcting its position with high precision, the point cloud data are less prone to distortion even when scanning while walking, resulting in high-precision point clouds with absolute coordinates. Large terrains can be measured in roughly 1–2 minutes, and the data can be immediately used for volume calculations of embankments and excavations.

• AR-based as-built verification and design sharing: Displays measurement data and 3D design models in AR on the smartphone screen. For example, displaying a pre-created design model in AR on site allows you to overlay the completion image on the real scene for verification. If buried pipes are recorded as point clouds and displayed in AR during subsequent work, everyone can perform construction that avoids buried objects. Sharing 3D models between clients and contractors during meetings is also expected to eliminate recognition gaps.

• Coordinate navigation (stake setting guidance): If you register target coordinates in advance in the app, the smartphone will guide the user to that location like a navigator. As you approach the destination, the display zooms in and arrow-based fine guidance will lead you precisely to the stake position. This function helps reliably find boundary markers hidden by vegetation or previously measured points.

• Positioned photos (location-tagged photos): As mentioned, this function records high-precision coordinates and camera orientation at the time of photo capture. On the cloud, photos are mapped to their shooting locations with icons, and arrows show which direction each photo was taken. For infrastructure inspections tracking aging changes, you can compare photos taken from the same location and angle over time. This removes the need to paste photos into paper ledgers or Excel for management and prevents recording mistakes.

Thus, a single LRTK Phone can cover a wide range from surveying to recording, inspection, and as-built verification. Tasks that previously required separate devices or software per use can be completed on site with just a smartphone and an LRTK Phone, which is a major advantage.

Comparison with conventional surveying methods

So, how does smartphone surveying with LRTK Phone compare to conventional methods? Let’s compare several aspects.

• Accuracy: LRTK Phone delivers horizontal ±1 cm (±0.4 in) and vertical ±2 cm (±0.8 in) levels of positioning accuracy. Conventional instruments like total stations and laser scanners also provide high accuracy, but LRTK Phone has the advantage that it can obtain absolute coordinates without reference points. Drone photogrammetry requires control points to achieve centimeter-level accuracy, whereas LRTK Phone can survey without placing markers on site.

• Work speed: Including equipment setup and post-processing, LRTK Phone is very fast. Positioning is possible immediately after power-up, and once point cloud scans are uploaded to the cloud you can immediately confirm and share results. Drone surveying requires time for flight planning and image analysis, and laser scanning takes time for setup and data processing.

• Cost: LRTK Phone is also advantageous in terms of acquisition and operating costs. By leveraging smartphones, it significantly reduces the cost of dedicated equipment. Since expensive surveying equipment, software, and specialized operators are not required, it is accessible even to small operators.

• Portability & constraints: The pocket-sized LRTK Phone is easy to handle and can flexibly measure in narrow spaces, indoors, or under trees. Drones cannot be used in no-fly zones or indoors, and laser scanners face difficulties with heavy equipment transport and tripod setup. With LRTK Phone, constraints due to terrain or environment are minimal, and surveying is possible wherever a person can go.

• Operability & personnel: Survey tasks that conventionally required two-person teams of skilled technicians can be performed intuitively by one person with LRTK Phone. Because it can be used without specialized knowledge, the hurdle for human resource development is lowered. This has significant implications as a response to serious labor shortages.

While smartphone surveying with LRTK Phone offers many advantages, it is not万能. For example, drones are suitable for rapidly surveying very large areas, and total stations may be preferable when millimeter-level precision is required for structural displacement measurements. By using conventional methods where appropriate and LRTK Phone for everyday surveying tasks, most routine surveying operations can be made more efficient with LRTK Phone.

Conclusion: The new surveying era enabled by field DX

Combining centimeter-level GNSS positioning (cm level accuracy (half-inch accuracy)), cloud sharing, and smartphone integration, LRTK Phone has the potential to dramatically change traditional surveying styles. If everyone carries a pocket-sized surveying device one per person, field data collection and sharing will become far more efficient and could become the core of construction DX (digital transformation). When high-precision location information becomes routinely available, site workers themselves, without relying on a specialized surveying department, will be able to take necessary measurements and share information in real time. This leads not only to productivity improvements but also to reduced errors and faster decision-making.

In the new era LRTK Phone opens, “surveying will no longer be a special task but rather an extension of daily work” becomes a reality. Carry a smartphone, scan the terrain in 3D on the spot, compare with design drawings, and immediately make construction decisions. That future is already taking shape. Spatial measurement, which used to be entrusted to specialists, is being democratized so that anyone on site can handle high-precision data. Surveying will evolve into a smarter, more seamless process with tools like LRTK Phone.

Make surveying on site simpler and more advanced. LRTK Phone is a major step toward that realization. If you have ever thought, “I wish we could survey more easily and accurately,” why not try simplified surveying with LRTK? You will likely gain a new experience that changes your concept of surveying.

FAQ

Q: What kind of product is the LRTK Phone? A: It is an ultra-compact RTK-GNSS receiver that attaches to a smartphone. Working with a smartphone, it enables centimeter-level positioning and offers various surveying and recording functions. Using a dedicated app, you can perform position measurements, point cloud scanning, AR display, and more.

Q: Can a smartphone really achieve such high-precision positioning? A: Yes. LRTK Phone uses high-precision RTK positioning technology, combining correction data from reference stations with satellite signals to reduce positioning errors. While regular smartphone GPS has errors of several meters (several ft), using LRTK Phone reduces errors to approximately 1–2 cm (about 0.4–0.8 in).

Q: Is specialized knowledge required for installation or operation? A: No. Basic operation follows guidance within the app, so specialized knowledge is not required. You do not need a surveyor’s license to use it, and even first-time RTK users can intuitively measure and share data. However, if you intend to submit surveying results as official survey records, specialist expertise may be required in some cases.

Q: What kinds of tasks can it be used for? A: It can be used for stake setting and layout, as-built management, land surveying, infrastructure inspection, construction progress measurement, and more. From single-point coordinate measurements to 3D terrain scanning, photo documentation, and AR design verification, one device covers a wide range of needs.

Q: Can it be used under buildings or bridges where GPS signals do not reach? A: By using “indoor positioning mode” or photo-positioning functions, LRTK Phone can record relative positions even in GPS-denied environments. For example, under a bridge you can acquire a reference position where GPS is available and then continue measurements under the bridge based on that reference. However, in completely underground spaces real-time positioning is not possible, so practical workarounds are needed depending on the situation.

Q: How are surveying data shared and exported? A: All measured data can be uploaded and managed on LRTK Cloud. To share with others, simply send a cloud-issued URL so they can view data in a web browser. For your own use, data can be downloaded from the cloud in formats such as CSV, DXF, or LAS for point clouds, and imported into your CAD or GIS software.

Q: Which smartphones are supported? A: Currently, iOS devices such as iPhone and iPad are supported (the dedicated app is iOS-compatible). The latest iPhones with LiDAR sensors are especially able to fully utilize LRTK Phone features. Please look for future updates regarding Android support.

Q: How is the battery life and continuous use time? A: The receiver’s internal battery provides up to about 6 hours of continuous positioning. Charging is via a USB Type-C port, and charging from a mobile battery is also possible. For long work sessions, carrying spare batteries is recommended.

Q: Is LRTK Phone an expensive product? A: Compared to conventional high-precision GNSS equipment or 3D scanners, LRTK Phone is priced to be accessible. Specific pricing requires inquiry, but it is realistic to equip one device per person, so adoption is progressing among small and medium construction companies and surveying offices.

Q: How will surveying change in the future? A: With the combination of smartphones and high-precision positioning devices, surveying will become more routine and familiar. As environments that allow real-time sharing and utilization of spatial information become established, construction workflows and inspection methods will change significantly. Tools like LRTK Phone will accelerate this shift, and in the future it may become normal for anyone on site to handle surveying data. We are in the midst of forming a new surveying norm.