Real-time sharing with cloud-enabled GNSS terminals! Survey data management made easy

1. What is a GNSS terminal? Accuracy and Practical On-site Deployment

First, let's clarify what a GNSS terminal is. GNSS is an abbreviation for Global Navigation Satellite System, a collective term for multiple satellite positioning constellations such as GPS (United States), GLONASS (Russia), Galileo (EU), and Japan's Quasi-Zenith Satellite System. A GNSS terminal refers to a device that receives signals from these satellites and determines its position (latitude, longitude, and altitude). Typically, smartphones and car navigation systems also incorporate GNSS receivers, but their positioning accuracy is on the order of several meters (several ft). In construction surveying and infrastructure works, many tasks—such as driving stakes according to the design (layout marking) and verifying as-built conditions—require centimeter-level accuracy (half-inch accuracy), so commercial GPS accuracy is insufficient.

This is where high-precision GNSS terminals come into play. By using correction techniques such as RTK (real-time kinematic) positioning, high-precision GNSS terminals can reduce satellite positioning errors to a few centimeters or less (a few cm; a few in). In the RTK method, a fixed receiver acting as a base station and a mobile terminal communicate, canceling error factors to compute a high-precision position in real time. This made surveys that previously required long observation times to achieve centimeter-level surveying (cm level accuracy; half-inch accuracy) possible instantly, and since the 1990s dedicated RTK-GNSS equipment has become common on civil engineering and construction sites. However, conventional high-precision GNSS equipment was typically large and expensive, and its operation generally required specialized knowledge and personnel. For example, it involved the hassle of setting up tripods and antennas on site, carrying heavy receivers while moving around, and operating the equipment with multiple people, making adoption difficult for small-scale contractors and local governments. In addition, organizing and transporting the data acquired by the equipment tended to take time, so even when positioning accuracy was improved, it was often hard to translate that into operational efficiency.

In recent years, new-generation GNSS terminals that address these challenges have emerged. One of them is a cloud-enabled GNSS terminal called “LRTK,” developed by a startup from Tokyo Institute of Technology. LRTK is a system that combines a smartphone with an ultra-compact RTK-GNSS receiver, and despite weighing just 165 g, and being compact enough to integrate with a smartphone, it is attracting attention as an “all-purpose surveying instrument” capable of centimeter-level positioning using RTK. It is revolutionary that by attaching the LRTK receiver to an iPhone using a dedicated case and simply launching an app, it can perform the role of surveying equipment that used to be stationary and weigh several kilograms in a palm-sized form. Because it enables high-precision positioning and is as easy to use as a smartphone for field staff without special training, it is increasingly being adopted at construction and surveying sites. Cloud-enabled GNSS terminals like LRTK are making positioning tasks that previously depended on specialist technicians accessible to anyone, and are beginning to make a major contribution to improving on-site productivity.

2. Field Challenges in Survey Data Management and Inefficient Procedures

Next, let's look back at the challenges of traditional survey data management. When bringing back survey results measured with high-precision GNSS or total stations from the field and organizing and sharing them within the company, in many cases it was necessary to go through multiple manual steps. For example, surveyors would copy the coordinates and feature information obtained in the field into a notebook or field book, or export data from surveying instruments onto a USB memory stick. Then, after returning to the office, they would transfer the data to a PC and import it into CAD software or transcribe it into Excel spreadsheets. Such bringing data back and manual transcription tasks not only took time and effort but also became a breeding ground for human error. If mistakes in copying numbers or mixing up files occurred, there was a risk of re-measurement, design revisions, and other rework.

Moreover, even data that was accurately measured on site could have its value halved by delays in sharing. Traditionally, surveyors could not share results with other team members or the client until they returned to the office and finished organizing the data. In some cases it could take several days from surveying to reporting, and during that time the site was forced to proceed using provisional information. Because the survey results could not be checked in real time, inefficiencies tended to arise—for example, measurement errors or omissions in the records might be discovered later, requiring re-measurement.

Furthermore, there were also challenges in managing photos. Traditionally, survey points and the photos taken had to be manually linked, and it could be difficult later to determine which location a photo depicted. As described above, the conventional surveying data management workflow 「on-site recording→bringing data back→transcription→sharing」 harbored many inefficiencies.

3. Five Benefits of Cloud-Enabled GNSS Terminals

So, how does introducing a GNSS terminal equipped with cloud connectivity resolve the aforementioned challenges? Here, we will specifically introduce the five main benefits that cloud-enabled GNSS terminals bring to the field.

• Share survey results immediately from the field – As soon as the survey is finished, you can upload the data to the cloud from the site. There is no need to open a laptop or copy files via USB; you can send the results with a single tap from a smartphone app. By the time you return to the office, the latest data will already be shared with all stakeholders, eliminating the time lag caused by waiting to hand over survey results.

• Prevent input errors with zero transcription work – Because data is automatically recorded in the app during surveying, transcription to paper logs or Excel is unnecessary. With no manual numeric entry or copying mistakes, you can drastically reduce rework caused by human error. Notes and comments can also be saved electronically on site, preventing omissions in the field records.

• Centralize data management in the cloud – All deliverables, such as measured coordinate information, photos, and point cloud data, are consolidated in the cloud. Anyone involved in the project can access the necessary survey data from a browser. By integrating information that had been dispersed across individual PCs and paper documents, the risk of data loss is reduced, and it also serves as a backup that allows past records to be checked at any time.

• Real-time coordination between the field and the office – Because the field and the office can constantly share data via the cloud, real-time collaboration is possible. For example, office staff can instantly check the positions of survey points and measurement values, issue additional instructions on the spot, or add comments to the data. Since feedback can be sent without waiting for the surveyor to return, missed measurements and errors can be discovered and corrected the same day, leading to faster decision-making.

• Easily share rich information such as photos and point clouds – Cloud-enabled GNSS terminals can acquire and share not only position coordinates but also photos and point cloud data linked with a smartphone’s camera and LiDAR functions. Captured photos are automatically tagged with high-precision position coordinates and camera orientation information, and can be displayed together with maps and point clouds on the cloud. This makes it easier to spatially understand “what is happening at this location on site.” Acquired 3D point clouds can also be viewed and measured directly in a cloud viewer, so everyone on the team can intuitively grasp the current situation without specialized software.

As described above, using cloud-enabled GNSS terminals not only greatly reduces the stress of data management and sharing, but also enables field teams and remote offices to act as one in grasping and assessing situations in real time.

4. LRTK Surveying and Synchronization Workflow Completed on a Smartphone

Now, let's look at the overall flow of how field surveying progresses when using the cloud-enabled GNSS terminal LRTK. The LRTK is a type of GNSS device designed to be attached to an iPhone. Attach the dedicated compact receiver to the back of the smartphone and take it to the site. When starting a survey, power on the LRTK device, launch the dedicated app on the smartphone, and connect the device via Bluetooth. If you set up reception of RTK correction information over the internet—such as the Geospatial Information Authority of Japan’s Continuously Operating Reference Stations network and QZSS “Michibiki” CLAS—the satellite position information will be corrected to centimeter-level accuracy (cm level accuracy (half-inch accuracy)) within a few tens of seconds, completing the positioning setup.

The operation during measurement is very simple. For example, if you want to measure the coordinates of a point, simply carry your smartphone to that location and tap the "Positioning" button in the app. The latitude, longitude, and altitude of your current position are recorded instantly. If necessary, using the average positioning mode for a few seconds allows you to obtain a more stable value by averaging multiple observations.

Positioning data are automatically tagged with time and sequential numbers and are accumulated on the app screen as a list of survey points. Because the app immediately performs conversion to the plane rectangular coordinate system and calculation of geoid height, coordinates obtained in the field can be used directly for design drawings and construction management. Instead of writing notes in a paper field book, you can add electronic memos and photos on the spot, and complete survey records with just a smartphone.

The data collected in this way is not just stored on the smartphone. When measurements are finished, you can run a cloud sync from the app with the push of a single button and upload the data to the LRTK cloud. If you are within coverage, transmission completes in seconds from the field, and colleagues in the office or at other sites can immediately check the results via the cloud. Of course, if measurements were taken outside coverage, moving later to a location with a network connection and synchronizing will upload the positioning data that had accumulated on the device to the cloud. In this way, a major feature of LRTK is that the entire surveying workflow—preparation, observation, recording, and sharing—can be carried out seamlessly on a smartphone, allowing the whole process, including data management, to be completed on site.

5. Examples of On-site Applications Using Photos, Point Clouds, and AR Features

A distinguishing feature of cloud-enabled GNSS terminals is that they can be used on-site not only to measure coordinates but also to leverage a variety of smartphone-linked functions. By using LRTK's photo documentation function, 3D scanning capability, and AR (augmented reality) display function, on-site information sharing and work efficiency can be further improved. Here, we will look at some concrete examples of their use.

High-precision photo records and comparison – When you take photos with the LRTK app, the images are automatically tagged with centimeter-level position coordinates (cm level accuracy (half-inch accuracy)) and the shooting orientation (direction) information. On the cloud, photos can be placed and displayed on maps and point cloud data, so it is immediately clear which location and which direction a photo captures. For example, in routine slope inspections, comparing photos taken from exactly the same position and angle as the previous time ensures that even subtle changes are not missed. Using LRTK's AR feature, you can display an arrow on the smartphone screen aligned with the coordinates and orientation of a previously taken photo, allowing you to retake the photo with the same composition. This enables accurate tracking of crack propagation and dramatically improves the accuracy of on-site records.

3D as-built capture using point cloud scanning – By utilizing smartphone‑embedded LiDAR scanners and cameras, you can also acquire a 3D point cloud by walking the site with LRTK. Simply walking around large sites or structures records the surrounding terrain and structures as a collection of points (point cloud) with high accuracy. Moreover, since an LRTK GNSS position is assigned to each measured point, point cloud distortions and positional offsets that often occur with a standalone smartphone are avoided. The resulting point cloud data can be synced directly to the cloud and viewed in a 3D viewer in a web browser without specialized software. Analyses such as measuring the distance between any two points on the point cloud or calculating area and volume for a specified region can also be performed easily in the cloud, so it can immediately be used for tasks such as calculating excavation volumes or verifying the finished shape of embankments.

AR機能による直感的な施工支援 – LRTK's AR display feature is a powerful tool that overlays survey and design data onto the site scenery. For example, by displaying a virtual stake at a pre-set target coordinate in the view through a smartphone, you can indicate an exact position even where a physical stake cannot be driven. Even in complex terrain, following AR arrows on the smartphone screen will navigate stake-driving operations, allowing even first-timers to reach the points without getting lost. Also, by AR-displaying the pre-construction 3D design model onto the actual site, clients and construction teams can share the finished image and identify potential issues in advance. It is also possible to verify on the spot whether construction can be carried out as planned. Because LRTK's high-precision positioning for AR displays experiences almost no positional drift, another key feature is that stakes and 3D models remain fixed in their correct positions even as users walk around. By utilizing the AR features in this way, survey results can be applied directly to on-site work, enabling intuitive and efficient construction management.

6. Key Points and Tips for In-House Implementation and Operation

When introducing cloud-enabled GNSS terminals such as LRTK in-house and using them in field operations, there are several points to consider.

• Start with a small-scale pilot implementation – Rather than rolling it out to all sites at once, first try it in a small project or an internal demo using a single device. Having on-site staff actually handle it allows them to get a feel for the operation and makes aligning it with current workflows smoother. Sharing the results of the pilot internally will deepen understanding of the implementation’s benefits and help reduce resistance at the sites.

• Optimal smartphones and communication environment for terminals – LRTK Phone is compatible with iPhone/iPad (iOS). Prepare compatible devices in advance and ensure they have the latest OS and the necessary storage capacity. A network connection is also important for real-time synchronization on site. In areas where mobile signals are weak, such as mountainous regions, enable Michibiki (CLAS) reception settings, or use portable Wi‑Fi or relay antennas, etc., to establish an environment that can stably perform high-precision positioning.

• Establishing cloud operation rules – As survey data are consolidated in the cloud, internal information-sharing flows will change. It is advisable to predefine permission settings that specify "who," "when," and "which data" can be accessed, and to decide folder management rules and naming conventions for each project. Make it standard practice to upload field-collected data to the cloud on the same day whenever possible, and, as needed, leverage automatically generated reports to reflect information in daily and other reports; institutionalizing such new workflows will maximize the benefits of using the cloud.

• Data integration with existing systems – Survey results downloaded from the LRTK cloud can be imported into the CAD software and GIS systems you currently use. Be sure to confirm in advance how to repurpose your existing deliverable formats and ledger management. In some cases, review your workflows and put in place systems so the whole company can reap cost savings and improved operational efficiency from adopting LRTK, for example by bringing surveying that was previously outsourced in-house.

• Daily maintenance and utilizing support resources – Ensure daily inspections and maintenance so GNSS terminals and smartphones can always be used in their best condition. Check the devices' remaining battery levels before heading to the field, and carry spare batteries and charging cables as needed. Pay attention to app and firmware update information and update to the latest versions to benefit from bug fixes and improved accuracy. Also, actively utilize manufacturer-provided manuals, support channels, and online communities, and accumulate your company's operational know-how for added peace of mind.

7. Finally: The Arrival of the “Anyone Can Survey” Era Supported by LRTK

Until now, surveying has relied on specialist technicians, and it was normal to carry it out with expensive equipment and teams of multiple people. However, the advent of cloud-enabled GNSS terminals is poised to greatly change that conventional wisdom. The system of smartphone surveying and real-time sharing enabled by LRTK suggests the dawn of a new era in which "anyone can survey". Individual site workers carry high-precision positioning tools in their pockets, take measurements immediately when needed, and share the data — such scenes are already becoming a reality in many places.

The arrival of this "anyone-can-survey" era will bring many benefits to the construction and infrastructure industries. In response to shortages of skilled surveyors and challenges related to generational transition, tools like LRTK promote the democratization of technology, creating an environment where anyone on site can carry out basic surveying tasks. As a result, schedule delays caused by waiting for surveys will be reduced, decision-making will speed up, and quality control will be strengthened. If a culture of immediately "measure and verify" on site takes root—without hauling heavy equipment or rescheduling to call in specialist teams—the style of construction management will be dramatically transformed.

LRTK is precisely the key solution for on-site DX (digital transformation). By combining familiar technologies—smartphones and the cloud—it has dramatically streamlined the processes of “measuring, recording, and communicating.” In future construction sites, the easy and accurate surveying supported by LRTK will become standard, and an era will arrive when anyone, immediately, and with high accuracy can take measurements. Why not ride this new wave at your site as well? This is a chance to dramatically improve the productivity and reliability of your operations by leveraging cutting-edge cloud-enabled GNSS terminals. In the world of "anyone can survey" that LRTK is pioneering, let’s move projects forward with unprecedented speed and peace of mind.