Measure point clouds with a smartphone and share a URL on the spot! Improve field operations with LRTK

Table of Contents

• Basics of point cloud measurement and the importance of data sharing

• Challenges of conventional point cloud data sharing

• Easy, high-precision point cloud capture with smartphone × LRTK

• Procedure for uploading captured point clouds to the cloud and sharing a URL

• Just open the URL! 3D point cloud viewing and comments with no special software

• Overlay with design data to check differences and visualize progress

• Benefits of introduction: time savings, labor reduction, error prevention, remote inspection

• Easy 3D surveying and point cloud sharing starting with LRTK

• FAQ (Frequently Asked Questions)

Basics of point cloud measurement and the importance of data sharing

In recent years, 3D measurement using point cloud data has attracted attention in construction and surveying sites. Point cloud data is a collection of countless points obtained by laser scanners or photogrammetry, each point having X, Y, and Z coordinates as 3D data. Traditionally, 3D surveying required expensive equipment and specialized technicians, but with LiDAR sensors built into modern smartphones, it has become possible to easily scan sites with handheld devices and acquire detailed point clouds. As a result, a wide range of professionals—from surveyors to construction managers and municipal employees—are now using 3D data.

The greatest advantage of point cloud measurement is that it can record the shape of a large area quickly and with high density. Unlike traditional methods that measure one point at a time, point clouds allow surveying that captures surfaces from lasers or photos, enabling non-contact and safe measurement of hazardous areas where people cannot enter. Because cross-sections and dimensional measurements can be made on the data after acquisition, mistakes like “I forgot to measure that spot” can be prevented. The 3D data obtained at the site is extremely useful, but to realize its full value, smooth data sharing between the field and the office and with clients is essential. If the latest field conditions measured in 3D can be shared instantly with stakeholders, they can check compliance from remote locations or issue instructions, dramatically improving the efficiency and accuracy of operations.

Challenges of conventional point cloud data sharing

However, sharing point cloud data using conventional methods presented various challenges. Due to the burden of handling large files and the constraints of specialized software, valuable 3D data tended to remain on site. Specifically, there are the following problems:

• Large data size: Point cloud files often range from hundreds of MB to several GB, making them difficult to send by email or chat tools. Transfers take time and storage is strained.

• Dependence on viewing environment: Recipients may not be able to open point cloud data unless they have a high-performance PC or dedicated viewer software. Specialized formats like LAS or PLY require compatible software, creating a high barrier for clients or supervisors to view the data.

• Effort and psychological barriers to sharing: Uploading to online storage and sharing links is an option, but the process can be cumbersome and is often avoided. While struggling with data sharing, people may resort to “just sending photos for now,” relying on 2D images and resulting in 3D data not being utilized.

Because of issues such as file size and viewing environment, the hurdle to share acquired point clouds outside the site has been high, and the information has often not been fully utilized.

Easy, high-precision point cloud capture with smartphone × LRTK

This is where the smartphone combined with high-precision GNSS—LRTK—comes in. Recently, some smartphones and tablets have built-in LiDAR sensors, enabling anyone to easily perform 3D scans of their surroundings. However, standalone smartphone GPS previously had meter-level errors, making it difficult to align captured point clouds with map coordinates or design drawings.

LRTK solves this problem. LRTK is a system consisting of a small GNSS receiver that can be attached to a smartphone and a dedicated app, using a correction technology called real-time kinematic (RTK) to achieve centimeter-level positioning even on a smartphone. RTK-GNSS provides position information with errors of only a few centimeters, so each point in the point cloud acquired by the smartphone’s LiDAR or camera is tagged with high-precision latitude, longitude, and elevation. As a result, even casually acquired point clouds can become high-precision 3D surveys with absolute coordinates in the global geodetic system. In fact, verification by the Ministry of Land, Infrastructure, Transport and Tourism confirmed that smartphone + RTK point cloud surveying meets the accuracy required for as-built management (about ±5 cm), and this method has been incorporated into procedural guidelines. Precision control that used to require specialized laser scanners or drone surveys can now be achieved with a smartphone and a small device.

The typical workflow is: attach the LRTK GNSS receiver to the smartphone (or connect via Bluetooth) and launch the dedicated app at the site. Once high-precision RTK positioning begins in the app, use the smartphone’s LiDAR scanning or photo capture functions to document the surroundings. For example, walking around a structure or terrain while scanning can quickly produce detailed 3D point clouds that include features tens of meters away. Because each point is assigned high-precision coordinates from real-time positioning, no time-consuming post-processing to align to control points is necessary. With simple operation, anyone can immediately create accurate point cloud models—this is the strength of smartphone × LRTK.

Procedure for uploading captured point clouds to the cloud and sharing a URL

Point clouds captured with LRTK can be uploaded to the cloud on the spot and shared via a link. Being able to immediately share the latest field conditions with stakeholders is a major advantage. The specific steps are as follows:

• Complete point cloud capture: When the point cloud scan is finished in the smartphone LRTK app, save the data.

• Upload to the cloud: Follow the app’s prompts to upload the captured point cloud data to cloud storage. A single tap starts the upload, and large point cloud data are automatically optimized and converted.

• Issue a shareable URL: Once the upload is complete, a unique URL that grants access to the point cloud is generated. The link can be viewed immediately in the app and copied for use.

• Share the URL with stakeholders: Send the issued URL by email or chat to the intended recipients. From the field, you can notify supervisors or clients in the office of the latest data via a URL.

By sharing via the cloud as described above, there is no need to send huge files individually. Because the workflow—from on-site point cloud capture → immediate upload → URL sharing—can be performed smoothly, there is no long delay before data is shared.

Just open the URL! 3D point cloud viewing and comments with no special software

Recipients of the shared link can use a 3D point cloud viewer simply by clicking the URL. A web browser–based viewer lets users display point clouds on PCs, tablets, and smartphones without installing special software. By dragging the screen, users can view the site in 3D from any angle, zoom into areas of interest, and intuitively measure distances or heights. Since the cloud-side data is optimized for operation without expensive workstations or specialized software, clients and supervisors can easily view 3D data, which is a major benefit.

Moreover, the viewer includes a comment function. For example, if a client views the point cloud and comments, “Is the finish here as designed?” the contractor can immediately identify the pointed location. Because stakeholders can communicate while looking at the same 3D data, information that is hard to convey by text or phone can be shared more easily. People who are not on site can grasp the situation as if they were there and exchange opinions, improving communication accuracy and reducing mistakes caused by differing perceptions.

Overlay with design data to check differences and visualize progress

Cloud point cloud viewers can also load design data (3D design models or digital drawings) and overlay them on point clouds. This allows comparison of the current point cloud with the planned design model in the same coordinate system, enabling quick checks on whether construction is proceeding as designed. Construction errors or differences in quantity—hard to notice on drawings—can be intuitively understood by color-coding differences in 3D. For example, areas constructed to the design height might be shown in blue or green, while areas with higher or lower fill than planned might be shown in red, visualizing site conditions with a difference heat map that overlays point cloud and design.

Point cloud data also serve construction progress management. If the site is scanned at each stage of work, comparing point clouds over time lets you remotely confirm “how far work has progressed” and “what changed since the last scan.” This not only quantifies as-built conditions but also helps detect schedule delays or construction mistakes early. By sharing the latest 3D data among all stakeholders and visualizing progress, mutual understanding and reporting/communication/consultation (known in Japanese as “horenso”) are streamlined, strengthening trust between the field and the office.

Benefits of introduction: time savings, labor reduction, error prevention, remote inspection

The workflow of measuring point clouds with a smartphone and sharing them via the cloud brings various benefits to field operations. Here are the main effects summarized:

• Time savings: Point cloud scans are completed far faster than traditional surveying with total stations, etc. In addition, real-time data sharing accelerates information transfer from the field to the office, speeding decision-making.

• Labor reduction: Since surveying can be completed by one person walking with a smartphone, measurement can be done efficiently even on sites with labor shortages. Because veteran technicians do not have to be present at every key point, it helps optimize staffing and reduce travel time.

• Error prevention: Recording the entire site as point cloud data reduces the risk of overlooked or missing measurements. Visualizing and sharing differences from the design also helps detect construction errors or misunderstandings early and prevent rework. Miscommunications due to differences in stakeholder understanding are also easier to resolve in 3D.

• Remote inspection: Because anyone can check the site’s 3D status via the cloud, remote supervision from a distant office is possible. The number of business trips and on-site inspections can be reduced, and online response is possible even when weather or infectious disease prevents physical site visits. Remote expert support and client briefings are facilitated, enabling efficient management and inspection.

Thus, smartphone point cloud measurement and URL sharing not only reduce time and cost but also offer many advantages in terms of quality and safety.

Easy 3D surveying and point cloud sharing starting with LRTK

Point cloud measurement and sharing with smartphone × LRTK strongly support digital transformation (DX) in the field. Without bulky equipment or advanced expertise, anyone can easily perform 3D surveying on site and share results immediately. LRTK in particular is a solution that integrates positioning devices, an app, and cloud services, so even surveying beginners can start using it without confusion. From uploading point cloud data to sharing, the process is completed in one stop, dramatically lowering the barrier to “measure and show.”

Please make effective use of on-site detailed data that was previously overlooked by leveraging LRTK. Information that could not be fully conveyed by paper drawings or photos can be shared as a three-dimensional point cloud model so that all stakeholders have the same image. The simplicity of being able to start immediately with just a smartphone and LRTK device is also attractive. Why not introduce a new workflow of 3D-ifying the site and sharing in real time to experience improved work efficiency and productivity? If you are interested, please feel free to contact us.

FAQ (Frequently Asked Questions)

Q. What do I need to measure point clouds with a smartphone? A. You need a smartphone equipped with a LiDAR sensor, a high-precision GNSS receiver called “LRTK,” and the dedicated LRTK app. This combination enables centimeter-level positioning on a smartphone to acquire detailed point clouds. Devices without LiDAR can still be used by generating point clouds from multiple photos, but LiDAR-equipped models allow efficient on-the-spot scanning.

Q. What level of measurement accuracy can be achieved? A. The smartphone + LRTK combination generally achieves high-precision point cloud surveying with errors of a few centimeters horizontally and vertically. This meets the accuracy required by national and municipal standards for as-built management (approximately within 5 cm) and has been confirmed in actual verifications. However, accuracy can be affected by surrounding conditions and satellite reception, so use in situations where stable positioning can be obtained.

Q. In what formats are point cloud data handled? A. Captured point cloud data is automatically converted and stored in visualization formats on the cloud so it can be displayed in a browser. The original point cloud files (such as LAS or PLY formats) are also stored in the cloud and can be downloaded for use in other software or submitted as deliverables as needed.

Q. Is it secure to upload data to the cloud? A. The LRTK cloud is designed with security in mind. Access to data is limited to those who know the shared link, and communications are encrypted. It is also possible to set access permissions per project. When sharing with external clients, data can be operated securely to prevent unnecessary dissemination.

Q. Can people without specialized knowledge use it? A. Yes. LRTK pursues simple usability so that non-ICT field personnel can handle it easily. The dedicated app can start surveying with a single button at the desired location, without complicated settings. The cloud point cloud viewer is also intuitive, focusing on basic functions like viewing and measuring, so even non-experts can use it without issue. Advanced analysis is available if needed, but the design prioritizes usability so anyone can get started.

Q. Can it be used in mountainous areas with no mobile coverage? A. Yes. The LRTK positioning device supports Japan’s quasi-zenith satellite system (Michibiki) CLAS (centimeter-class augmentation service). Therefore, even in areas without mobile coverage, centimeter-level positioning is possible by receiving augmentation signals from satellites (an optional off-line antenna is required). Uploading to the cloud can be done later when moving to an area with reception, but measurement itself is possible offline.

Q. Does it fall short compared to expensive laser scanners or drone surveys? A. It depends on the application. Traditional terrestrial laser scanners and drone photogrammetry are suited for large-scale, highly detailed 3D modeling and can acquire very dense, high-precision point clouds. However, they involve high equipment costs and operational effort, making frequent on-site use challenging. Smartphone + LRTK, on the other hand, offers ease and immediacy, with sufficient accuracy for routine construction management and small- to medium-scale site recording. It is recommended to use it for quick everyday “snapshots” while combining it with conventional equipment as needed. In large civil engineering sites, it is common to use drones for broad-area capture and supplement fine details from the ground with smartphone scans.

Q. What applications and sites are suitable? A. Smartphone point cloud measurement with LRTK is used across a wide range of civil and building scenarios. For example, in road and land development as-built management, scanning the finished terrain and comparing it with design data helps with quality control. For bridge and tunnel maintenance, point clouds are used to record deterioration for repair planning. In disaster sites, a single technician can walk through the area to acquire point clouds and share them immediately with distant support headquarters. For buried utility work, scanning the location of pipes and cables before backfilling helps future excavation. In this way, LRTK contributes to field DX across construction management, disaster response, and infrastructure inspection.