Challenges in the Construction/Civil Engineering Industry and Expectations for DX

In recent years, the construction and civil engineering industry has faced serious challenges such as chronic labor shortages, inefficient workflows, and difficulty passing on skills. For example, the number of construction workers, which was about 6.85 million in the 1990s, has fallen to around 4.7 million today—an almost 30% reduction. On-site aging is progressing: more than 30% are aged 55 or older, while younger workers (29 or under) make up only about 10%. Massive retirements of experienced technicians raise concerns about the severing of institutional knowledge, and combined with declining new entrants, the shortage of skilled on-site personnel is accelerating. The image of construction as a 3K workplace (kitanai—dirty, kitsui—tough, kiken—dangerous) with long hours and hazardous tasks further deters young people from joining the industry.

Labor shortages have caused project delays, declined contract acceptances, and rising costs across the industry, making overall productivity improvement a major issue. Traditional construction sites still rely heavily on analog work—plans and manual labor—leading to rework caused by surveying mistakes or misreading designs. Understanding complex drawings on site requires seasoned intuition, which is a high barrier for younger workers. Against this backdrop, expectations for digital transformation (DX) have never been higher. The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has promoted initiatives like i-Construction with goals such as improving on-site productivity by 20% by fiscal 2025, encouraging public and private adoption of ICT, AI, and IoT to drive construction DX. DX is seen as a trump card to solve labor shortages and skill transfer issues while enhancing operational efficiency and sophistication.

Amid this trend, a particularly notable on-site DX solution combines high-precision positioning technology with AR (augmented reality). By using real-time positioning that minimizes positioning error and AR guidance that overlays digital information on the site, construction management and surveying tasks that previously relied on analog methods can be dramatically modernized. This article explains in detail the new form of civil engineering DX enabled by high-precision positioning × AR guidance and introduces concrete use cases and effects.

Overview and Strengths of High-Precision RTK Positioning and AR Guidance Technologies

First, let’s outline what high-precision positioning and AR guidance are. RTK positioning stands for Real-Time Kinematic, a positioning technology that adds real-time correction information to GNSS (satellite positioning) to reduce GPS errors of several meters down to a few centimeters or less. It uses correction signals from a base station and signals from Japan’s quasi-zenith satellite "Michibiki" (such as CLAS) to calculate one’s position with high accuracy. Because centimeter-level positioning—previously difficult with standard GPS—becomes possible, it achieves the precision required for civil engineering work.

AR (augmented reality) guidance overlays digital information such as 3D models and guide lines onto real-world images captured by the camera of a smartphone, tablet, or other device to support tasks. Implemented via dedicated goggles or existing smartphone apps, users can simultaneously view the site and the design data through the screen. Because it can display the design as if projected onto the actual site, it makes it intuitive to understand "where and what to build," dramatically improving spatial awareness and communication.

Combining RTK high-precision positioning with AR guidance enables AR displays that do not shift by centimeters. In conventional AR, limitations of device GPS and sensors could cause meter-level display errors, making traditional AR impractical for construction sites requiring millimeter- or centimeter-level precision. With RTK corrections, the AR digital model can be overlaid in virtually the exact physical location, allowing on-site verification and instructions with perfect alignment between plans and actual conditions.

High-precision RTK × AR guidance offers several strengths not found in conventional technologies. First is the reduction of human error. There is no need to mentally match surveying results and drawings; users can confirm overlays on-site, preventing oversights and misunderstandings that lead to construction mistakes in real time. With the correct design positions always shown in AR, installers can detect and correct misalignments immediately when placing rebar or bolts. Second is streamlined work processes. Compared to the traditional method of repeatedly surveying, checking, and marking layouts while referring to paper drawings, AR guidance can navigate users to required positions simply by walking with a device. It eliminates the time spent locating points and transcribing measurements, significantly shortening overall work time. Third is improved information sharing. Design information and survey data displayed in AR can be shared via the cloud in digital form, enabling remote stakeholders to view the current situation simultaneously. This makes remote construction management possible because office-based personnel can review AR visuals and generated data to make decisions and give instructions without being physically present.

In summary, by using RTK-derived high-precision positioning as a foundation and offering intuitive visual support via AR, an environment is created where "anyone can measure and construct accurately." Tasks that once depended on veteran intuition and experience are digitized, allowing even newcomers to achieve high-precision results by following machine guidance. This fusion of technologies exemplifies the DX (digital transformation) of civil engineering sites.

Use Cases of On-Site DX with LRTK

What can this high-precision RTK × AR technology actually do on site? Below are representative use cases using a solution called "LRTK," which combines an RTK device attached to a smartphone with an AR app.

• Streamlining piling layout work: Labor-intensive piling layout tasks such as setting reference points and measuring distances can be made smart with AR guidance. With LRTK, the device screen shows the designed pile positions as 3D markers, guiding workers to the target points while they scan the site. Even on sites with poor visibility like dense vegetation, AR can pinpoint "put the pile here," so nothing is missed. Where survey crews previously used a transit or laser with two or more people to stake out pile positions, LRTK enables accurate pile location determination by a single person simply walking with a device. This dramatically speeds up piling and layout marking while reducing human errors.

• Enhancing as-built control: AR is also powerful for checking the as-built state (the shape of completed structures or terrain). LRTK can automatically compare on-site 3D measurement data (point clouds) with the design model in the cloud and generate color-coded heat maps of elevation differences. Displayed on a device, this makes it easy to identify spots where embankment or pavement thickness deviates from design values. Previously, identifying as-built discrepancies required taking survey points, analyzing numbers, and coloring plans—a time-consuming process. With AR heat maps, defective areas are color-marked on the spot, allowing immediate remediation without additional layout marking. Quality control personnel can perform inspections simply by holding up a device, significantly reducing the effort required for as-built verification.

• Quality control in structure construction: High-precision AR is also useful at bridge and tunnel construction sites. Overlaying the planned 3D model on the structure during construction allows real-time checks to ensure that member placements and angles are correct. It’s possible to verify whether steel frames or piping are installed to the designed positions and gradients by comparing AR models with the actual structure. Even small misalignments can be detected on-site to avoid later rework like repositioning bolts. AR can also place models of heavy machinery or temporary installations and overlay them with actual site conditions to easily simulate interference—for example, verifying crane swing ranges relative to surrounding structures and adjusting plans if issues are found. Spatial problems that are hard to grasp from drawings alone can be shared intuitively with AR, helping eliminate recognition gaps among stakeholders. Visualizing construction procedures in AR also helps convey the finished image to junior engineers, serving as an educational tool to support construction management. If AR screens are recorded as photos or videos, they’re useful for later inspections or reporting, producing highly communicative documentation easily. These capabilities help ensure construction quality and safety at a high level.

• Speeding up earthwork volume measurement: LRTK can greatly streamline the estimation of fill and excavation volumes in earthworks. Traditionally, survey crews measured site cross-sections and calculated volumes or generated point clouds from drone imagery—specialized tasks. With LRTK, point cloud data obtained by scanning a site with a smartphone is automatically assigned coordinates, allowing immediate on-site volume calculations. For example, at a development site, scanning terrain before and after grading with LRTK enabled fill volume calculation in a few clicks. This enables real-time daily progress management and residual soil calculations, making progress monitoring and reporting much faster.

• Simplifying point cloud data acquisition: Obtaining point cloud data—a 3D record of the site—is surprisingly easy with LRTK. By combining a smartphone with a compact RTK antenna, users can acquire point clouds with absolute coordinates at centimeter-level accuracy in a short time by simply taking photos or performing a simple scan. For example, by scanning a site like taking photos, anyone can capture extensive point clouds including targets 60 meters away. Previously, expensive, bulky laser scanners and post-processing coordinate alignment were required; that effort is no longer necessary. Scanning a trench interior with LRTK before backfilling, for instance, saves the underground piping point cloud with geographic coordinates. Later, by pointing a smartphone at the excavation site, workers can AR-visualize the underground pipe positions, directly reducing the risk of damaging other buried objects. In renovation projects for existing structures, acquiring current point clouds in advance and comparing them with design models allows efficient evaluation of additional work quantities and interference checks. The accessible point cloud measurement and AR visualization enabled by LRTK create new workflows across survey, design, and maintenance management.

As these use cases show, LRTK promotes DX across surveying, construction management, and infrastructure maintenance, holding great potential to enhance on-site productivity and safety. Next, let’s look at the effects obtained by actual implementation from the perspectives of labor-saving, efficiency, and quality improvement.

Impact on Labor Saving, Efficiency, and Quality Improvement

The effects achieved by introducing high-precision positioning × AR guidance can be summarized in three keywords: labor saving, efficiency, and quality improvement.

Labor saving: The greatest impact is labor saving, which helps alleviate workforce shortages. Tools like LRTK enable work that previously required two to three people—such as surveying and layout marking—to be performed by a single person. With a smartphone surveying device per person, all required points can be measured without pairing a skilled surveyor with an assistant, creating flexibility in personnel allocation. AR guidance navigates novices as they work, allowing them to perform tasks at a certain accuracy even without an experienced supervisor. This also aids skill transfer by enabling less-experienced engineers to become productive through technology, allowing limited personnel to cover more sites and making project execution easier even amid severe labor shortages.

Efficiency: Digital technologies bring dramatic improvements in work efficiency. Sites adopting AR + RTK report substantial reductions in time required for surveying, inspection, and surveys. For example, displaying a design model in AR and taking photos was enough to create meeting materials, reducing the need for additional drawing work or re-surveying. In some cases, terrain surveys that used to take half a day were completed in less than an hour. Cloud integration allows on-site data to be shared instantly with the office, shrinking information transmission lag. Remote decision-making and approvals have been expedited by sharing AR visuals, enabling quicker consensus. These effects reduce unnecessary waiting and travel time, shortening total project duration. The efficiency gains can also free resources for other important tasks and contribute to work style reforms such as reduced overtime.

Quality improvement: High-precision digital technologies directly raise construction quality. Consistent construction at the design-specified positions and elevations reduces variability in as-built outcomes and stabilizes product quality. Preventing dimensional mistakes and omissions caused by human error reduces rework and complaints. Accumulating detailed 3D data and records from construction processes enhances traceability in quality control. During inspections, AR can highlight points needing checking, facilitating smoother client inspections and third-party verification. High-precision RTK × AR is a strong ally for producing structures that reliably achieve targeted performance. Visualizing invisible elements like piping also improves safety, which in turn reduces quality risks.

Future Prospects for Civil Engineering DX and an Invitation to Adopt LRTK

High-precision positioning × AR guidance is becoming the new on-site norm. In Japan, general contractors, small and medium construction firms, and local governments alike are beginning to consider and pilot these technologies. Domestically, trials of high-precision AR for visualizing buried utilities and as-built inspection in infrastructure maintenance and public works have shown improvements in safety and productivity. Overseas, systems that realize centimeter-accurate AR outdoors have emerged, drawing attention for enabling intuitive on-site confirmation and sharing of complex 3D data. Looking ahead, leveraging digital technologies will be indispensable to maintain high-quality infrastructure while responding to a shrinking labor force. DX will accelerate the transition from "construction relying on labor and experience" to "construction supported by data and technology," radically changing workflows and work styles.

Within this trend, LRTK is attracting attention as a key enabler of on-site DX. By simply combining a smartphone with a small antenna, LRTK can perform high-precision positioning, point cloud measurement, and AR displays with no positional offset on a single device—making DX benefits accessible to everyone. Its ease of use—no complicated equipment setup or specialized knowledge required; just bring it to the site and power it on—is another major attraction. Without investing in expensive dedicated equipment, existing smartphones can quickly become surveying tools, lowering the adoption barrier for smaller companies and sites and making one-device-per-person operation feasible.

The labor-saving revolution LRTK brings is not limited to efficiency gains; it has the potential to transform work styles themselves. When digital technology and on-site skills converge, the future construction site we imagine will evolve into a smarter, more sustainable form. To avoid falling behind the accelerating wave of civil engineering DX, it is important to start by introducing digital technologies where you can test them on site. Solutions like LRTK are an ideal first step in the labor-saving revolution. Once used, they often provide an eye-opening experience in surveying and construction management. Those small experiences will accumulate and eventually lead to industry-wide mindset change and productivity improvement. The future of construction sites beneath our feet is already in motion. Why not take this opportunity to adopt high-precision positioning × AR guidance and step together into a sustainable future for civil engineering?