LRTK LiDAR Point Cloud Utilization Frontline: High-Precision 3D Scanning Anyone Can Do Easily

Table of Contents

• Introduction

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

• Centimeter-Level Positioning Realized by LRTK (cm level accuracy (half-inch accuracy))

• Workflow for Utilizing 3D Scans On Site

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

• Convenience Brought by the LRTK Solution

• Summary

• Frequently Asked Questions

Introduction

In construction, surveying, and civil engineering sites, digital transformation (DX) using 3D point cloud data has been accelerating in recent years. Point clouds, which can record a site in full three dimensions, are valuable information resources useful across design, construction management, and as-built inspection. However, traditionally performing such high-precision 3D scans required specialized laser scanners or surveying instruments and demanded skilled operation.

A method attracting attention is the combination of LiDAR sensors on smartphones and tablets with RTK positioning. Recent iPhone and iPad models include compact LiDAR sensors, enabling anyone to easily capture surrounding point clouds. By applying LRTK (a centimeter-level positioning solution) to the positioning information, the captured point cloud can be assigned public coordinates and achieve surprisingly high positioning accuracy. In other words, “anyone” can perform a “high-precision 3D scan on the spot”.

This article introduces the cutting edge of this 3D scanning technique under the keyword “LRTK LiDAR point cloud.” We explain concretely how to acquire point clouds with smartphone LiDAR, the data utilization flow after acquisition (viewing in a viewer, drafting, as-built checks, etc.), and discuss the significance of converting scans to public coordinates and the importance of ensuring accuracy. Finally, we naturally touch on the convenience of our LRTK solution, hoping to encourage adoption at your sites.

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

Traditionally, acquiring 3D point cloud data commonly involved laser scanners costing millions of yen. Today, however, anyone can easily perform surrounding 3D scans using the LiDAR sensor built into the latest smartphones and tablets. For example, iPhone models from the iPhone 12 Pro onward and certain iPad Pro models include LiDAR; by launching a dedicated app and moving the device while walking, you can obtain real-time point clouds of surrounding structures and terrain.

The major appeal of smartphone LiDAR scanning is that it is intuitive and easy. Moving the device feels much like recording a video, so even people without training on specialized equipment can handle it. Heavy tripods or generators are unnecessary, and you can quickly scan needed areas while walking around the site, offering excellent mobility. The scan results are visualized on the screen on the spot, so you can immediately check for omissions. There is no need to bring data back and run long analyses like with traditional photogrammetry; you can judge on site whether you have acquired sufficient point cloud data.

Of course, smartphone LiDAR has physical limitations. The sensor’s effective range is generally several meters—about a 5 m (16.4 ft) radius—and capturing wide areas in detail requires moving while scanning. On the other hand, as long as the operator can walk the area, it is possible to continuously capture large-area point clouds. In practice, the latest point cloud capture apps use AR-based self-localization, and there are examples of continuously scanning an entire office floor or slopes longer than 100 m (328.1 ft). By walking key points, a single person can cover somewhat larger sites, responding flexibly to needs like “I want to measure this spot too,” which were difficult with conventional equipment.

Furthermore, smartphone LiDAR point cloud data becomes even more useful when combined with photogrammetry. LiDAR scans can capture point clouds quickly, and if photos from the smartphone camera are recorded simultaneously, color information (textures) can be added later and fine details can be enhanced. Some dedicated apps offer a “detailed point cloud scan” function that fuses LiDAR and photos to acquire high-density colored point clouds. This flexibility—being able to choose the appropriate 3D scan mode with just a smartphone—is another attraction.

Centimeter-Level Positioning Realized by LRTK (cm level accuracy (half-inch accuracy))

Point clouds obtained with smartphone LiDAR alone are useful for understanding site conditions and relative measurements. However, to truly use them in operations, absolute positional accuracy is critical. The built-in GPS in smartphones typically has meter-level accuracy, making it difficult to align acquired point clouds to plan drawings or reference coordinate systems. That’s where LRTK (a high-precision GNSS positioning solution) comes in.

LRTK is our proprietary solution that makes the real-time kinematic (RTK) GNSS positioning technology easy to use on smartphones. RTK is a technique that corrects GNSS positioning errors by using observation differences between a base station and a rover, which traditionally required specialized expensive equipment. LRTK combines a smartphone, a compact receiver, and correction information delivered over the internet to allow position determination within a few centimeters of error. For example, typical smartphone GPS has errors around 5–10 m (16.4–32.8 ft), but with LRTK you can achieve horizontal positioning accuracy of ±1–2 cm (±0.4–0.8 in) and vertical accuracy of about ±3 cm (±1.2 in). This level of accuracy rivals that of conventional first-class GNSS survey equipment, yet the devices fit in a pocket.

When positioning information from LRTK is combined with smartphone-acquired point clouds, you can assign public coordinates (absolute coordinates) to the entire point cloud. That means the point cloud is mapped to the correct location and elevation within real geodetic systems (such as global geodetic coordinates or Japan’s plane rectangular coordinate system). This makes it dramatically easier to overlay 3D scan data on CAD drawings or GIS maps later or to integrate it with other survey data. Normally you would need post-processing (georeferencing) to align point clouds to known reference points, but with LRTK georeferencing is effectively completed during measurement.

The important point is that high-precision positioning and point cloud acquisition are realized in a one-stop workflow. Using an LRTK-compatible app (such as our “LRTK Phone” app), a single smartphone can perform RTK positioning and LiDAR scanning simultaneously, automatically adding latitude, longitude, and elevation information to the acquired point cloud. By simply walking around the site with the device, the surveying workflow, including downstream tasks, can be completed without waiting for a surveyor’s presence or heavy equipment setup. There are increasing cases where, after a few minutes of instruction, site personnel themselves can acquire point clouds with absolute coordinates. The centerpiece enabling the “high-precision 3D scan anyone can do” is precisely this centimeter-level positioning by LRTK.

Workflow for Utilizing 3D Scans On Site

Let’s follow the basic workflow to see how 3D scanning combining smartphone LiDAR and LRTK can be used in actual operations. Below we explain the sequence from point cloud acquisition to data checking, sharing, drafting, and as-built verification.

Point Cloud Acquisition Procedures and Tips

First is on-site point cloud acquisition. After setting up a LiDAR-equipped iPhone/iPad with LRTK positioning, start scan mode in the dedicated app. Then simply point the device at the target (terrain or structure) and walk slowly while scanning the surroundings. The LiDAR sensor continuously obtains distance information and the app displays the point cloud in real time. Because LRTK records the device’s positional coordinates with high precision simultaneously, the point cloud is assigned absolute coordinates at this stage.

There are several tips for smoothly acquiring high-quality point clouds:

• Maintain an appropriate distance: Keeping about 1.5–2 m (4.9–6.6 ft) from the target yields good point density and accuracy. Too far makes points sparse; too close increases occluded areas.

• Face the LiDAR toward the target: Avoid tilting the smartphone too much and move with the LiDAR sensor roughly facing the target (parallel to within about 30°) for better results. Extreme angles increase hard-to-measure areas.

• Keep a consistent scanning direction: Generally move forward in one direction and avoid backing up or making sudden lateral movements. If lateral movement is necessary, sidestep while facing the target (crab-walk) to get better results.

• Move slowly and steadily: Keep your arms and elbows as stable as possible and move the device smoothly without sudden swings. Cover the area like filling in with a single stroke, and avoid repeatedly passing over the exact same spot to reduce data jitter.

By following these points, even those without field experience can acquire high-quality point clouds in a short time. With practice, you’ll learn how to scan complex structures without omissions. After scanning, stop the processing in the app and confirm the data is properly saved (many apps automatically back up to the cloud).

Immediate Point Cloud Confirmation and Measurements

After acquisition, immediately check the data on site. With dedicated viewer functions and cloud integration, you can display 3D point clouds on the smartphone right away. Inspect the recently captured point cloud from various viewpoints to confirm the necessary areas are fully scanned and that there are no gaps or holes. If you find omissions, you can perform additional scans on the spot, minimizing rework.

In the viewer you can rotate, zoom, and inspect point clouds in detail, and basic measurements are also possible. For example, you can measure distances between two points, calculate the area or slope of a surface, or even compute volumes on site. This lets you instantly determine whether the scanned data covers the target sufficiently and whether its accuracy meets your needs. In civil engineering, being able to calculate excavation or fill volumes on site aids quantity management and as-built checks, offering significant benefits.

For instance, scanning a cross section of an embankment and calculating the fill volume can be done on the smartphone with a single tap. Tasks that used to require bringing survey data back to dedicated software for analysis can now be completed on site, greatly accelerating decision-making. The ability to confirm and utilize point cloud data on site turns 3D scanning from mere recording into a real-time measurement and verification tool.

Sharing Point Clouds and Drafting

Point cloud data captured on site can be uploaded to the cloud and shared as is. Using the LRTK cloud service, simply pressing sync on the smartphone will save point cloud data, the positioned coordinates, photos, and more to the cloud. Colleagues or supervisors in the office can view the uploaded point cloud in a 2D/3D web viewer via a browser—no software installation required—so even PCs without dedicated software can access the data. This seamless sharing enables “measure on site → share/report immediately.”

Cloud-hosted point clouds are not only viewable but can be used in various ways. You can extract arbitrary cross sections from the point cloud and produce drawings, or extract coordinate values of important points into tables. You can also import the acquired point cloud into CAD or BIM software to overlay and compare with design drawings or 3D models. If the point cloud already has public coordinates assigned via LRTK, it will align perfectly in CAD with the design drawings, eliminating troublesome alignment work. Point cloud data can be downloaded in standard formats (LAS, XYZ, etc.) for detailed analysis in other software as needed.

Additionally, sharing point clouds via the cloud makes it easy for remote experts to advise or verify quality. For example, a construction manager in the office can check the latest point cloud and issue real-time instructions like “please excavate a bit more here.” If the cloud service supports commenting or comparing past and new data, it also helps with time-series change management and report creation. Smoothly sharing acquired point clouds among stakeholders and using them consistently through drafting and reporting is a major strength of on-site DX.

Application to As-Built Verification

Point cloud data is powerful for as-built verification and quality control. Traditionally, as-built checks compared surveyed values on site with design drawings, but using point clouds allows measuring and recording the entire site at once to verify as-built conditions without omissions.

For example, scanning a concrete structure after casting captures surface smoothness and dimensions digitally. Overlaying this with the design 3D model makes it visually clear which parts match the design and which have excesses or deficiencies. Similarly, point clouds help check pavement thickness in roadworks or final elevation on a development site. Unlike spot checks with tapes or levels, point clouds capture variation across whole surfaces, improving quality control accuracy.

Saving point clouds as evidence for as-built inspections provides persuasive material for later third-party verification. Subtle slopes or irregularities that photos may not convey can be shown numerically with point clouds. Showing a 3D model to the client also helps align understanding. Such data-driven as-built management aligns with the growing practice of CIM utilization (Construction Information Modeling). Point clouds obtained with a smartphone and LRTK make it easy to adopt this process even on small to medium sites.

AR Overlay of Design Data

A high-precision scanning environment enabled by LRTK and smartphones is also applicable to AR (augmented reality) uses beyond point cloud capture. Specifically, you can project design-stage 3D models or drawing data (BIM/CIM models) onto the smartphone screen in the site coordinate system and compare them with the real world. With LRTK accurately tracking the smartphone’s position and orientation, the AR overlay aligns with reality with minimal offset.

Using this feature, you can support operations like stakeout for piles or equipment installation via AR. Virtual stakes or marks at design positions can be displayed, allowing workers to mark locations on site based on the AR reference. Tasks that previously required surveying instruments to derive angles and distances can now be confirmed by looking at the model while holding a smartphone and saying “the pile head comes here.” If you acquire point clouds before and after buried-works execution, you can visualize the location of underground pipes or cables in AR after backfilling. This lets you know buried object locations without excavation, which is invaluable for future maintenance or renovations.

Thus, point cloud scanning and LRTK-based high-precision alignment are powerful for “feeding measured data back into real space.” It’s not just measuring—the measured data can intuitively support on-site decisions, which is gaining attention as a new construction management style.

Significance of Assigning Public Coordinates and the Importance of Ensuring Accuracy

As noted earlier, matching 3D point cloud data to public coordinate systems and ensuring positioning accuracy are key to full operational use. Here we summarize their significance.

First, about public coordinates (absolute coordinates). In Japan, public surveys generally require results to be in government-defined coordinate systems (plane rectangular coordinates based on the global geodetic system or latitude/longitude). Even if data is used only within a site, it is desirable that it be on a unified coordinate system considering the need to compare multiple datasets or to connect with future works. Relative point clouds from a single smartphone will later require registration to known points, increasing effort and error risk. If point clouds measured on site are assigned public coordinates using LRTK, they may be usable directly as 3D data for electronic deliverables without baseline surveys or post-processing.

Next, the importance of accuracy. Needless to say, errors of a few centimeters matter in surveying and construction management. For example, a 5 cm misalignment of a structure’s centerline can constitute a construction defect, and whether ±2 cm is acceptable for road width measurements depends on the case. Smartphone LiDAR’s shape accuracy depends on the environment, but if LRTK provides cm-level positional accuracy, you can confidently use the measurement results for on-site quality control. Conversely, point clouds with only usual GPS accuracy (meters) may have detailed shapes but still include errors of several meters depending on the target, making them impractical.

High-precision coordinates also enhance the long-term value of data assets. If past data are saved in rigorous coordinate systems, future re-surveys and comparisons are straightforward. When integrating multiple point clouds into a single large model, having public coordinates on each makes it possible to join them without misalignment, like assembling a puzzle. All these benefits are realized only with LRTK’s centimeter-level positioning.

In short, ensuring “positional certainty” is indispensable for point cloud utilization, and LRTK is a highly rational and powerful means to that end. High-precision georeferenced point clouds become a reliable “digital twin” of the site, forming the basis for all analyses and decisions.

Convenience Brought by the LRTK Solution

Finally, here is a summary of the convenience provided by an LRTK solution that makes smartphone LiDAR + RTK positioning easy to use on site. Our offering, LRTK Phone, is an all-in-one platform enabling surveying, point cloud recording, and cloud integration with just an iPhone. Key benefits for site deployment include:

• Mobility and ease of use: Surveying can be completed with a smartphone-sized device weighing about 165g and an iPhone. There is little burden in transporting equipment, and you can work one-handed even in confined or high locations.

• Single-person operation: LRTK RTK positioning runs automatically, removing the need for assistants or the traditional two-person surveying teams. A single site person can perform point cloud measurement and verification, helping alleviate labor shortages.

• Multifunctional integrated app: The app provides point cloud scanning (fast and detailed modes), AR-based design projection, geotagged photos (coordinates and orientation), coordinate navigation (guidance to arbitrary points), distance/area/volume measurements, and more—all within one app. There is no need for separate devices or software, and data transfer between functions is seamless.

• Real-time cloud sharing: Measurement data can be synchronized to the cloud on the spot, eliminating the hassle of copying data via USB after returning to the office. Using the cloud’s 3D viewer, you can measure distances and areas, overlay multiple point clouds and design models, and instantly share information with stakeholders who don’t have dedicated software.

• Cost efficiency: Deployment is far less costly than acquiring specialized 3D laser scanners and high-precision GNSS equipment. You can leverage existing smartphones to reduce initial investment, and fewer devices mean lower maintenance costs and less failure risk.

These advantages have promoted LRTK solution adoption across municipalities and construction companies nationwide. For example, local governments have started using LRTK-equipped smartphones for rapid disaster-site recording, enabling less-experienced staff to perform accurate damage assessments. In construction, reports include “significant time savings in as-built management for earthworks” and “measurements previously outsourced to specialists now completed in-house.” These outcomes stem from the combination of ease of use and data reliability unique to LRTK LiDAR point clouds.

The barrier to introducing high-precision 3D scanning at your site is no longer high. By leveraging an LRTK solution, tasks that were previously impractical can be performed efficiently. If you are considering site DX or operational improvements, try this new approach.

Summary

The combination of smartphone LiDAR sensors and LRTK high-precision positioning has ushered in an era where anyone can easily perform high-precision 3D scans. Without relying on traditional specialized equipment, site personnel can record surroundings in 3D at needed times and immediately put the data to use—this is a strong driver for DX in the construction and civil engineering industries.

This article explained the flow from acquiring LRTK LiDAR point clouds to their utilization and highlighted their benefits and potential. The ease of smartphone LiDAR, the positioning accuracy provided by LRTK, and the efficiencies from cloud integration and AR use together bring immeasurable productivity gains. In particular, high-precision point clouds assigned public coordinates dramatically increase the value of site measurement data and directly contribute to reducing downstream effort and improving quality.

Without being constrained by traditional practices or expensive equipment, start using smartphone + LRTK point cloud utilization even on small sites. You will likely be surprised by its simplicity and usefulness. We hope to contribute to enhancing your site capabilities through the LRTK solution. Experience the latest trends in high-precision 3D scanning on your site.

Frequently Asked Questions

Q1. What preparation 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. Supported devices include LiDAR models such as iPhone 12 Pro and later or iPad Pro (4th generation and later). With an internet connection, you can receive correction information via LRTK and perform positioning and point cloud acquisition. No special surveying qualifications or difficult settings are required—just follow the app’s instructions.

Q2. What level of accuracy can be achieved? Can a smartphone really be that accurate? A. Yes—under appropriate conditions you can expect *approximately ±1–2 cm horizontally and ±3 cm vertically*. This rivals conventional high-end GNSS survey equipment. Standalone smartphone GPS typically has 5–10 m (16.4–32.8 ft) errors, but LRTK greatly reduces satellite positioning errors using RTK. High accuracy requires good satellite visibility outdoors; in tunnels or urban canyons among tall buildings, satellite reception may be poor and accuracy may degrade, in which case consider additional measures (setting up a base station or post-processing).

Q3. Is there a limit to the area that can be scanned with smartphone LiDAR at once? A. The LiDAR sensor’s effective range is a few meters, but by walking while scanning you can continuously capture point clouds for *areas on the scale of tens to 100 m (328.1 ft)*. For example, walking in a straight line records a wide swath along that path, and you can cover an area roughly the size of a sports ground in a single continuous scan in some cases. However, capturing extremely large areas (e.g., several hundred meters square) in high detail in one pass is unrealistic; in such cases divide the area and scan multiple times, then merge the data. LRTK Phone also has a photogrammetry mode, so you can supplement areas out of LiDAR range with photo-based data.

Q4. Even if enhanced by LRTK, isn’t a smartphone still inferior to professional equipment? What are the trade-offs? A. Smartphones excel in ease of use and mobility, but compared with dedicated equipment they do have disadvantages in sensor performance and environmental durability. For example, commercial laser scanners can measure up to 100 m (328.1 ft) with millimeter precision, while smartphone LiDAR reaches only a few meters and has slightly coarser resolution. Also, dedicated equipment is generally more reliable in rain or harsh environments. However, LRTK’s positioning accuracy is comparable to professional gear, and for everyday targets within about 5–10 m (16.4–32.8 ft) smartphone measurements provide practical accuracy and repeatability. The key is to use the right tool for the job: use conventional equipment for millimeter-precision or long-distance measurements, and smartphone + LRTK for mobility-focused tasks requiring centimeter accuracy. In many field cases, smartphone accuracy is sufficient, so we recommend starting with smartphone surveying.

Q5. How can the acquired point cloud data be used? Can it be handled in CAD or other software? A. Acquired point cloud data can be displayed in the *LRTK cloud 3D viewer* and used for distance and area measurements. You can create cross sections, compare point clouds, and more in the cloud. Point clouds can also be exported in standard file formats and imported into CAD or point cloud processing software. For example, download as LAS or an XYZ coordinate list and load into your CIM tool to compare with design data. Using high-precision coordinate lists and photos acquired simultaneously can greatly streamline report generation and as-built drawing creation.

Q6. Can people who are not good with technology operate it? I’m worried about on-site operation. A. Rest assured. LRTK-compatible apps are *user-friendly by design*, with intuitive operations for surveying and scanning. For example, main app controls such as “Start Positioning” and “Start Point Cloud Scan” are one-tap operations. Results can be checked visually in a 3D view, so there is no need to interpret complex numbers. There are cases where workers unfamiliar with ICT began using the system after a short training of a few tens of minutes and soon performed point cloud measurements independently. If you get stuck, on-screen guides and our support services are available to help, so even first-time users can operate confidently. Many users say that once accustomed, it is even easier than using a transit or level.

The above answers common questions about LRTK LiDAR point cloud utilization. Please make use of high-precision, easy 3D scanning to improve efficiency and promote DX at your sites.