Table of Contents

• Introduction

• Easy 3D Point Cloud Scanning Anyone Can Do with Smartphone LiDAR

• Centimeter-Level Positioning Achieved with LRTK

• Workflow for Using 3D Scans on Site

• The Significance of Assigning Public Coordinates and the Importance of Ensuring Accuracy

• Convenience Brought by the LRTK Solution

• Conclusion

• Frequently Asked Questions

Introduction

In construction, surveying, and civil engineering, DX (digital transformation) using 3D point cloud data has accelerated in recent years. Point clouds that can record a site in three dimensions are a valuable information resource that aids a wide range of tasks from design and construction management to as-built inspection. However, until now, performing high-precision 3D scans typically required specialized laser scanners or surveying instruments, and operation demanded skilled technicians.

A new approach that is attracting attention combines the LiDAR sensors in smartphones and tablets with RTK positioning. Recent iPhone and iPad models include compact LiDAR, allowing anyone to easily capture surrounding point clouds. By applying LRTK (a centimeter-level positioning solution) for location information, you can assign public coordinates to the captured point cloud and achieve surprisingly high positioning accuracy. In short, “anyone” can now perform “high-precision 3D scans on the spot.”

This article introduces the forefront of this latest 3D scanning technique under the keyword “LRTK LiDAR point cloud.” We explain how to capture point clouds with smartphone LiDAR, the workflow for using the captured data (viewing in a viewer, drafting drawings, as-built checks, etc.), and discuss the significance of converting scans to public coordinates and the importance of ensuring accuracy. Finally, we naturally mention the convenience of our LRTK solution, hoping to encourage adoption in your field operations.

Easy 3D Point Cloud Scanning Anyone Can Do with Smartphone LiDAR

Traditionally, obtaining 3D point cloud data commonly involved laser scanners that cost several million yen. Nowadays, however, you can use the LiDAR sensors built into modern smartphones and tablets to easily scan the surrounding 3D environment. For example, iPhone 12 Pro and later models and iPad Pro models include LiDAR; by launching a dedicated app and walking around while pointing the device, you can capture point clouds of surrounding structures and terrain in real time.

Scanning with smartphone LiDAR is attractive because it is intuitive and easy to use. Since you move the device as if recording a video, people without specialized equipment training can handle it. Heavy tripods and generators are unnecessary, and you can quickly scan needed areas while walking around the site, offering excellent mobility. Because point cloud capture is visualized on the screen on site, you can immediately check for any omissions. There is no need to take data back for long analysis like conventional photogrammetry—you can judge on site whether you have captured sufficient point cloud data.

Of course, smartphone LiDAR has physical limitations. The sensor’s effective range is generally a few meters (approximately a 5 m (16.4 ft) radius), so to capture large areas in detail you need to move while scanning. On the other hand, as long as the operator can walk the area, it is possible to capture continuous, wide-area point clouds. In fact, the latest point cloud capture apps use AR-based self-position estimation, and there are cases where you can continuously scan an entire office floor or slopes longer than 100 m (328.1 ft). By walking key routes, a single person can cover somewhat large sites, flexibly meeting the “just measure this too” needs that were difficult with traditional equipment.

Furthermore, smartphone LiDAR point clouds become even more useful when combined with photogrammetry. LiDAR scans prioritize speed in capturing point clouds, but if the phone’s camera records photos at the same time, you can later add color (texture) to the point cloud or enhance detail. Some dedicated apps offer a “detailed point cloud scan” function that fuses LiDAR and photos to produce high-density point clouds with color. This flexibility—switching between scan modes with a single smartphone depending on the situation—is another attractive feature.

Centimeter-Level Positioning Achieved with LRTK

Point clouds obtained with smartphone LiDAR are useful for understanding site conditions and relative measurements. However, to truly use them in work, absolute positioning accuracy is extremely important. Conventional smartphone GPS accuracy is on the order of several meters, making it difficult to align captured point clouds to plan drawings or a reference coordinate system. Enter LRTK, a high-precision GNSS positioning solution.

LRTK (pronounced “L-R-T-K”) is our proprietary solution that makes real-time kinematic (RTK) GNSS positioning easily usable on smartphones. RTK corrects GNSS positioning errors by using observation differences between a base station and a rover, and historically required expensive specialized equipment. LRTK combines a smartphone, a small receiver, and correction data delivered over the internet to achieve positioning within an error range of a few centimeters. For example, where typical smartphone GPS has errors around 5–10 m, using LRTK can improve horizontal accuracy to about ±1～2 cm (±0.4～0.8 in) and vertical accuracy to about ±3 cm (±1.2 in). This level of accuracy rivals conventional class-1 GNSS survey instruments, yet the equipment fits in your pocket.

When you combine LRTK positioning information with point clouds captured on a smartphone, you can assign public coordinates (absolute coordinates) to the entire point cloud. In other words, the point cloud is mapped to the correct position and elevation in a real-world geodetic coordinate system (such as the global geodetic system or Japan’s plane rectangular coordinate system). This makes it dramatically easier to overlay scanned 3D data on CAD drawings or GIS maps or to integrate it with other survey data. Ordinarily, georeferencing point clouds to known control points requires post-processing, but with LRTK the georeference is effectively completed during data capture.

The key point is that high-precision positioning and point cloud capture are realized in one stop. Using an LRTK-compatible app (such as our “LRTK Phone” app), a single smartphone can perform RTK positioning and LiDAR scanning simultaneously, automatically tagging the captured point cloud with latitude, longitude, and height. Just walk around site with the device in hand, and surveying tasks including downstream steps are completed without needing a surveyor’s presence or heavy equipment setup. There are increasing examples where, after only a few minutes of instruction, on-site staff themselves are able to acquire point clouds with absolute coordinates. The centimeter-level positioning provided by LRTK is literally the heart that enables “high-precision 3D scans anyone can do.”

Workflow for Using 3D Scans on Site

Let’s follow the basic workflow of how 3D scanning with smartphone LiDAR and LRTK can be used in practice. We step through the process from point cloud capture to data verification, sharing, drafting, and as-built checks.

Procedure and Tips for Point Cloud Capture

First, point cloud capture on site. After setting up an LRTK positioning environment on an LiDAR-equipped iPhone/iPad, start the scan mode in the dedicated app. Then point the device at the target (terrain or structure) and slowly walk while scanning the surroundings. The LiDAR sensor continuously measures distances, and the app displays the point cloud in real time. Because LRTK records the device’s position coordinates with high accuracy simultaneously, the point cloud is assigned absolute coordinates at this stage.

There are some tips to capture smooth, high-quality point clouds.

• Maintain an appropriate distance: Keep about 1.5～2 m (4.9～6.6 ft) from the target to achieve good point density and accuracy. Too far produces sparse points; too close increases blind spots.

• Face the LiDAR toward the target: Avoid tilting the phone too much; moving with the LiDAR sensor roughly facing the target (parallel to within 30°) is effective. Extreme angles increase areas that are hard to measure.

• Keep a consistent scan direction: Basically move forward in one direction and avoid backing up or sudden lateral movement. If you must move sideways, face the target and sidestep (crab-walk) to get better results.

• Move slowly and steadily: Keep your arm and elbow as stable as possible; do not swing the device suddenly. Cover the area like filling it in in a single stroke, and avoid repeatedly passing over the same spot to reduce data jitter.

If you follow these points, even those without site experience can acquire high-quality point clouds in a short time. With practice, you will learn how to scan complex structures without missing areas. When scanning is complete, stop the point cloud processing in the app and confirm the data is properly saved (many apps automatically back up to the cloud).

Immediate Confirmation and Measurement of Point Cloud Data

After capturing point clouds, check the data on site immediately. Dedicated viewer functions and cloud integration allow you to display 3D point clouds on your smartphone right away. Inspect the newly captured data from various viewpoints to confirm that the necessary areas were scanned and that there are no gaps or holes. If omissions are found, you can do supplementary scanning on the spot, minimizing rework.

In the viewer you can rotate, zoom, and inspect details, and basic measurements are possible. For example, you can measure the distance between two points, calculate the area or slope angle of a surface, and some tools even perform volume calculations on site. This lets you instantly determine whether the captured areas are sufficient and whether the accuracy meets your needs. In civil engineering, being able to compute excavation or embankment volumes on site supports quantity management and as-built verification, which is a major benefit.

For example, scanning a cross-section of an embankment and calculating the embankment volume can be done on a smartphone with a single tap. Tasks that previously required returning with survey data and analyzing it in specialized software can now be completed on site, greatly speeding decision-making. Being able to confirm and utilize point cloud data on site turns 3D scanning into a real-time measurement and verification tool rather than mere documentation.

Sharing Point Clouds and Drafting Drawings

Point cloud data captured on site can be uploaded to the cloud and shared as is. With the LRTK cloud service, a single sync tap on the smartphone stores point cloud data, measured coordinates, and photos in the cloud instantly. Colleagues and supervisors in the office can view uploaded point clouds with a 2D/3D viewer via a web browser. Since it runs in the browser without installing software, PCs without dedicated software can still view the data. Smooth data sharing between field and office enables seamless “measure on site → share/report immediately.”

Cloud-stored point clouds are not only viewable but can be used in various ways. For example, you can extract arbitrary cross-sections from point clouds to generate drawings, or extract coordinate values of important points into tables. You can also import captured point clouds into CAD or BIM software to overlay and compare with design drawings or 3D models. If the point cloud already has public coordinates assigned by LRTK, it will line up exactly on CAD, eliminating cumbersome alignment tasks. Point cloud data can be downloaded in standard formats (LAS, XYZ, etc.) for detailed analysis in other software as needed.

Sharing point clouds via the cloud also makes it easy for remote specialists to advise or verify quality. A construction manager can check the latest point cloud from the office and give real-time instructions like “please excavate a bit more here.” If the cloud platform supports adding comments and comparing past and current data, it also helps with time-series change management and report generation. Smoothly sharing captured point clouds among stakeholders and using them consistently for downstream drafting and reporting is a major strength of on-site DX.

Application to As-Built (Completion) Checks

Point cloud data is also powerful for as-built control, verifying post-construction shapes and dimensions. Traditionally, as-built checks compared design values to measured site values; using point clouds allows the entire site to be measured and recorded at once, enabling thorough as-built verification without omissions.

For example, scanning a concrete structure after casting captures the entire surface’s smoothness and dimensions digitally. Overlaying this with the design 3D model lets you visually identify where there is surplus or deficit relative to the design. Similarly, point clouds are useful for checking pavement thickness in roadworks or finished elevations on graded land. Unlike manual checks with measuring tapes or levels, point clouds allow you to grasp variations across entire surfaces, improving quality control accuracy.

Saving point cloud data as evidence for as-built inspection provides persuasive documentation for later third-party verification. Subtle slopes and undulations that photos alone cannot convey can be expressed numerically with point clouds. Showing 3D models to stakeholders is often more effective for aligning understanding. This data-driven as-built control aligns with the future-required use of CIM※ (※Construction Information Modeling). With point clouds obtained by smartphone and LRTK, even small and medium-sized sites can easily implement CIM-like practices.

Overlaying Design Data with AR

The high-precision scanning environment using LRTK and smartphones also applies to AR (augmented reality) uses beyond point cloud capture. Specifically, you can project design 3D models or drawing data (BIM/CIM models, etc.) onto the smartphone screen aligned to the on-site coordinate system and compare them with the real world. Because LRTK accurately tracks the smartphone’s position and orientation, AR-displayed virtual models have minimal positional offset and align closely with reality.

This feature enables AR-assisted layout work such as stake positioning and equipment placement. Virtual stakes or marks at design positions can be displayed, and workers can mark the site accordingly. Tasks that used to rely on surveying instruments to derive angles and distances can now be checked by looking at the model while holding a smartphone to confirm “the stake head should be here.” Also, by capturing point clouds before and after burying utilities, you can visualize underground pipes or cables in AR even after backfilling. Knowing the location of buried elements without excavation is highly useful for future maintenance or renovation.

Thus, point cloud scanning combined with LRTK’s high-precision alignment is powerful in “feeding measured data back into real space.” It does not end with measurement; measured data can provide intuitive on-site decision support, representing a new style of construction management.

The Significance of Assigning Public Coordinates and the Importance of Ensuring Accuracy

As mentioned, a key to fully using 3D point cloud data for work is matching to a public coordinate system and ensuring positioning accuracy. Here we summarize those points again.

First, public coordinates (absolute coordinates). In Japan, public surveying results are generally required in coordinate systems set by the national government (plane rectangular coordinate systems based on the global geodetic system or latitude/longitude). Even for data used only within a site, being on a unified coordinate system is desirable if you may need to cross-reference multiple datasets or connect to future work. Point clouds captured only relative to the smartphone will require later alignment to known points, increasing effort and error risk. If you assign public coordinates to point clouds measured with LRTK on site, you may be able to use them directly as three-dimensional electronic deliverables without separate control-point surveys or post-processing.

Next, the importance of accuracy. Needless to say, errors of a few centimeters can be critical in surveying and construction management. For example, a structural centerline off by 5 cm could result in construction defects, and whether ±2 cm is acceptable for road width measurements depends on the case. While smartphone LiDAR’s geometric accuracy depends on the environment, if LRTK ensures centimeter-level positional accuracy, you can confidently use the measurement results for on-site quality control. Conversely, if a point cloud’s positions were determined only by normal GPS (several meters), even with detailed shapes captured, the data could include meter-level positional errors and be unusable in practice.

Moreover, having high-precision coordinates increases the value of the data as a long-term asset. When re-surveying another section in the future, past data saved in a precise coordinate system makes comparison easy. When integrating multiple point clouds into a single large model, having public coordinates on each point cloud allows them to join like puzzle pieces without offset. All these benefits are realized only with the centimeter-level positioning that LRTK provides.

In short, ensuring “positional certainty” is essential for point cloud utilization, and LRTK is a highly rational and powerful means to achieve that. Highly accurate, well-positioned point cloud data becomes a reliable “digital twin” of the site and forms the basis for all analyses and decisions.

Convenience Brought by the LRTK Solution

Finally, we summarize the convenience of the LRTK solution that makes smartphone LiDAR + RTK positioning easy on site. Our offering, LRTK Phone, is an all-in-one platform that completes surveying, point cloud recording, and cloud linkage with just an iPhone. Here are the main benefits when introducing it on site.

• Mobility and ease of use: Surveying can be completed with a smartphone-sized device weighing about 165 g and an iPhone. There is no burden of transporting heavy equipment, and you can work one-handed in narrow or high places.

• Single-person operation: LRTK RTK positioning operates automatically, eliminating the need for assistants or the traditional two-person surveying teams. One on-site person can perform point cloud measurement and verification, helping to alleviate labor shortages.

• Multifunctional integrated app: A single app provides high-speed and detailed point cloud scanning, AR-based design data projection, surveying photos (photos with coordinates and orientation), coordinate navigation (guidance to arbitrary points), distance/area/volume measurement, and more. There is no need to prepare separate devices or software, and data transfer between functions is smooth.

• Real-time cloud sharing: Measurement data can be synchronized to the cloud on site, eliminating the bother of copying data via USB after returning to the office. You can measure distances and areas with a 3D viewer in the cloud, overlay multiple point clouds and design models, and immediately share information with stakeholders who do not have dedicated software.

• Cost efficiency: Introducing this solution costs far less than assembling specialized 3D laser scanners and high-precision GNSS instruments. You can use an existing smartphone to reduce initial investment, and fewer devices mean lower maintenance costs and reduced failure risk.

These advantages have driven adoption of the LRTK solution across municipalities and construction companies nationwide. For example, local governments have begun using LRTK-equipped smartphones to quickly record disaster sites, enabling even inexperienced staff to make accurate damage measurements. In construction, feedback includes “time required for as-built checks with heavy machinery was greatly reduced” and “measurements that used to be outsourced to specialists are now completed in-house.” These outcomes reflect the unique combination of ease of use and data reliability provided by LRTK LiDAR point clouds.

Introducing high-precision 3D scanning technology in your field is no longer a high hurdle. With the LRTK solution, you can efficiently tackle detailed surveying and recording tasks that were previously impractical. If you are considering field DX or workflow improvement, try this new approach.

Conclusion

The combination of smartphone LiDAR sensors and LRTK high-precision positioning has brought an era in which “anyone can easily perform high-precision 3D scans.” Without relying on specialized instruments, on-site staff can record surroundings in 3D at the necessary moment and use the data immediately—this capability is a strong driving force for DX in the construction and civil engineering industries.

This article covered the workflow from capturing LRTK LiDAR point clouds to their utilization and highlighted the advantages and potential. The convenience of smartphone LiDAR, the positioning accuracy of LRTK, cloud integration, and AR use together produce significant efficiency gains. In particular, high-precision point clouds with public coordinates greatly enhance the value of surveying data and directly contribute to downstream labor savings and quality improvement.

Rather than being bound by traditional practices or the notion that expensive equipment is required, start using smartphone + LRTK point cloud workflows even on small sites. You will likely be surprised by their simplicity and usefulness. We hope to contribute to improving your on-site capabilities through the LRTK solution. Experience the latest trends in high-precision 3D scanning on your site.

Frequently Asked Questions

Q1. What preparations and equipment are needed to use LRTK and smartphone LiDAR? A. Basically, you only need a *LiDAR-equipped iPhone or iPad* and our *LRTK Phone system* (high-precision GNSS receiver and dedicated app) to get started. LiDAR-capable devices include iPhone 12 Pro and later and iPad Pro (4th generation and later). With an internet connection, you can receive LRTK corrections and perform positioning and point cloud capture. No special surveying qualifications or difficult setup are required—just follow the app instructions to complete preparation.

Q2. What level of accuracy can be achieved? Is a smartphone really that accurate? A. Yes—under suitable conditions, you can expect about ±1～2 cm (±0.4～0.8 in) horizontally and ±3 cm (±1.2 in) in elevation. This accuracy is comparable to high-end GNSS surveying instruments. Standalone smartphone GPS typically has errors of about 5～10 m (16.4～32.8 ft), but LRTK greatly reduces satellite positioning errors using RTK technology. To achieve high precision, you need a clear outdoor environment with sufficient GNSS signal reception. In tunnels or urban canyons among tall buildings, satellite reception can be poor and accuracy may drop; in such cases consider alternative measures (setting up a base station or post-processing).

Q3. Is there a limit to the area that smartphone LiDAR can scan at once? A. The LiDAR sensor’s effective range is a few meters, but by moving while scanning you can continuously capture areas on the order of tens to 100 m (328.1 ft). For example, walking in a straight line records along your path, and in area terms you might cover the size of a sports ground in a single continuous scan. However, capturing very large areas (e.g., several hundred meters square) in high detail in one pass is not realistic; in that case divide the area and scan in multiple passes, then merge the data. LRTK Phone also has a photogrammetry mode, allowing you to supplement areas beyond LiDAR’s reach with photo-based reconstruction.

Q4. Even if it’s high-precision gear, isn’t it still just a smartphone? Are there shortcomings compared to traditional surveying instruments? A. Smartphones excel in ease of use and mobility, but they do fall short of dedicated instruments in sensor performance and environmental robustness. For example, commercial laser scanners can measure to millimeter accuracy at 100 m, while smartphone LiDAR reaches only a few meters with somewhat coarser point resolution. Dedicated instruments are also more reliable in rain or harsh conditions. However, LRTK provides positioning accuracy comparable to professional gear, and for typical short-range tasks (within about 5～10 m (16.4～32.8 ft)) a smartphone delivers practical accuracy and repeatability. The ideal approach is to “use both”: rely on specialized instruments when millimeter precision or long-range measurement is required, and use smartphone + LRTK for mobility-focused tasks requiring centimeter accuracy. In many real-world applications, smartphone accuracy is sufficient, so starting with smartphone surveying is recommended.

Q5. How can the captured point cloud data be used? Can CAD and other software handle it? A. Captured point clouds can be displayed in a *3D viewer on the LRTK cloud*, and used for distance and area measurements. You can create cross-sections, compare point clouds, and other processing in the cloud. Point clouds are exportable in standard file formats, so importing into CAD or point cloud processing software is straightforward. For example, download as LAS or XYZ coordinate lists and load into your CIM tools for comparison with design data. If you also captured high-precision coordinate lists and photos, using them together streamlines report creation and as-built drawing production.

Q6. Can people who are not good with machines operate this? Any concerns about on-site operation? A. Rest assured. LRTK-compatible apps are *user-friendly*, designed so that surveying and scanning are intuitive. For example, app buttons are simple—major operations like “Start Positioning” and “Start Point Cloud Scan” are executed with one tap. Results are reviewed visually in a 3D view, so you don’t need to interpret complicated numbers. In practice, field workers unfamiliar with ICT have begun using the system after training of just a few tens of minutes and successfully performed point cloud measurements. If you get stuck, on-screen guidance and our support services will assist, so even first-time users can operate it on site. Many find it easier than using traditional transit or level instruments once they are used to it.

We have answered common questions about using LRTK LiDAR point clouds. Please take advantage of high-precision, easy 3D scanning to improve your operational efficiency and promote DX.