On-site Communication Transformed by AR in Civil Engineering: Eliminating Perception Gaps with Clients

Table of Contents

• Introduction

• Challenges of Traditional On-site Communication

• How AR Technology Transforms Communication - Preventing Construction Errors and Improving Quality - Closing Perception Gaps with Clients - Rapid Response to Design Changes and Reaching Consensus - Remote, Real-time Information Sharing

• Field Cases of AR Use

• What Is Simple Surveying with LRTK?

• FAQ

Introduction

In recent years, the introduction of AR (augmented reality) technology into the civil engineering field—often referred to as AR civil engineering—has attracted attention. AR that overlays design data onto the real site view via smartphones or tablets is a technology that can greatly contribute to improving construction management accuracy and reducing construction errors. Because stakeholders can share on-site the completed-image that was hard to grasp from paper drawings, it fills the perception gap between clients and contractors and revolutionizes on-site communication. This trend also aligns with DX (digital transformation) advancing in the construction industry and initiatives such as *i-Construction* promoted by the Ministry of Land, Infrastructure, Transport and Tourism.

This article explains the challenges that traditional on-site communication in civil engineering has faced and the benefits AR technology offers to solve them. It also introduces concrete scenes showing how AR use smooths consensus building with clients, and finally presents the next-generation tool “Simple Surveying with LRTK” that allows anyone on site to easily use AR and surveying.

Challenges of Traditional On-site Communication

On civil engineering sites, discrepancies often arise between clients (owners) and contractors (builders) in reading drawings and sharing the completed-image, causing various problems. Here are the main challenges.

• Construction errors due to differences in drawing interpretation: Drawings convey only planar information, so it is not easy for on-site staff to accurately understand the designer’s intended completed form. Misreading 2D drawings has often led to mistakes such as installing rebar or pipelines in the wrong position or misunderstanding attachment locations of structures, resulting in rework later.

• Insufficient transmission of design changes or adjustments during construction: Even if design changes occur during work, the latest information may not reach all workers, causing mistakes where construction continues according to outdated drawings. Redistributing paper drawings or explaining verbally creates time lags in information sharing, and it is difficult to ensure everyone on site is fully informed.

• 2D materials fail to convey the completed image well: For clients, it is not easy to imagine the finished product from drawings or perspective images alone. For example, comments like “I can’t picture the final form from the drawings” or “I don’t know how the surrounding landscape will actually change” are common. As a result, the image held by the client can diverge from the contractor’s understanding before completion.

• Perception gaps between client and contractor: The above factors can combine to create subtle differences in image between client and contractor regarding the finished form. Even if attendees feel they’ve explained sufficiently in meetings, full mutual understanding may not be achieved, and at completion there is always a risk of dissatisfaction such as “This is not what I expected” or comments like “I wasn’t told” or “This is different from what I imagined.”

As shown, traditional communication methods have limits in transmitting drawing information and sharing the completed image, and perception gaps have led to construction errors, rework, and unnecessary friction. So how does AR technology address these challenges?

How AR Technology Transforms Communication

By using AR to visualize design information on site, AR delivers dramatic effects against the above challenges. Below are the main ways on-site communication changes when AR is employed.

Preventing Construction Errors and Improving Quality

With AR technology, you can overlay a 3D model derived from design drawings onto the current construction status in real time. On site, you can compare the structure under construction with the designed 3D model to immediately check for discrepancies or mistakes. For example, you can confirm through a tablet whether rebar or piping is positioned according to the drawings and, if there is an error, correct it the same day. This allows early detection and correction of major construction errors, preventing rework. The result is improved quality and shorter schedules, enabling smoother progress until handover to the client.

Closing Perception Gaps with Clients

By using AR to display the post-construction image on site, clients and contractors can discuss while sharing the same visual. Traditionally, the image a client forms from drawings and the image held by the contractor can differ subtly. But with AR, for instance, showing a 3D model of the planned bridge or road overlaid on the actual site landscape allows the client to intuitively understand the final form. As the saying goes, “seeing is believing,” and because both parties can view the same AR imagery during discussion, it becomes a powerful means to close perception gaps.

In practice, site meetings using AR tend to prompt immediate, concrete feedback from clients such as “This matches my image” or “Could we lower the height here a bit?” Contractors can quickly adjust the design plan and display alternatives in AR, so misunderstandings can be resolved on the spot and consensus formed quickly. AR visualization reassures clients and contributes to building trust across the project.

Rapid Response to Design Changes and Reaching Consensus

When design changes or additional requests arise during construction, AR allows the changes to be visualized and verified immediately on site. Modifications that are hard to convey by swapping paper drawings or verbal explanation become obvious when presented as a 3D model. For example, a discussion like “What would it look like if we raised this retaining wall by another 50 cm (19.7 in)?” can be displayed in AR on the spot for client and contractor to review together. This enables immediate on-site decision-making and markedly streamlines the review and approval process for additional works.

Because all stakeholders share the same post-change image and can agree on it, troubles such as “We weren’t informed” or “Our understandings differed” are avoided. Consequently, the time required to reach consensus with the client is drastically reduced and the risk of project delays due to plan changes is lowered.

Remote, Real-time Information Sharing

AR technology also excels at information sharing with remote locations. Even if a client cannot visit the site every time, on-site staff can live-stream AR-displayed footage from a tablet or share the latest AR-derived site data (photos or point cloud models) via the cloud, allowing real-time grasp of construction status from the office. With the recent spread of online meetings, AR makes it possible for client and contractor to discuss while viewing the “same scene” even through a screen. Remote meetings can be vivid and practical, achieving communication without perception gaps despite physical distance.

Moreover, sharing comparison footage of as-built (completed structure) photos taken in AR against the design model lets stakeholders conduct visual progress reporting and status explanations. This makes explanations to clients or higher authorities easier and speeds up decision making. Tasks that were previously handled via meeting materials or reports can be performed quickly and accurately using AR-driven “visualization.”

Field Cases of AR Use

Now imagine how on-site communication changes with AR by looking at actual use scenes.

Example of a site meeting for a bridge construction: A construction manager uses an AR app on a tablet to overlay a life-size 3D model of the future bridge onto the construction site. The client can stand on site and, through the tablet, see a virtual bridge spanning the real landscape and concretely understand “how the scenery will change when completed.” The completed image, which is difficult to convey only by text or speech, can be shown as integrated into the actual scenery with AR, earning praise from clients like “It’s very easy to understand.”

In this scene, contractor and client are discussing while viewing the same AR imagery, which reduces misunderstandings like “Our images differ” and significantly smooths communication. For example, if the client worries “Would this girder height block the surrounding view?” the contractor can immediately alter the model height and show it. By manipulating the AR model to present alternatives, the parties can discuss and agree on design adjustments on the spot. The combination of BIM/CIM 3D models and AR allows verifying the actual sizes and dimensions of components and structures on site, offering the secondary benefit of detecting design inconsistencies or potential construction errors earlier.

In this project, assuming the client is located remotely, AR footage was also shared via the cloud. Contractors uploaded high-precision site data and AR-overlaid footage obtained using a system called LRTK to the cloud, and the client reviewed it via a web browser from the office. This created an environment where the client could timely check the as-built state and provide comments even when not on site. The number of days needed for consensus formation was greatly shortened compared to before, accelerating the project decision-making cycle.

Thus, AR use is profoundly changing on-site communication and consensus-building processes. AR, which brings the feeling of “sharing the entire site during discussion,” is likely to become a new standard for civil engineering sites. For clients and contractors to progress projects as a unified team, AR-driven visualization is becoming an indispensable element.

What Is Simple Surveying with LRTK?

Finally, as a solution to easily realize the AR use described above on site, we introduce “Simple Surveying with LRTK.” LRTK is a next-generation surveying and AR integrated tool developed by Reflexia Inc., a startup originating from Tokyo Institute of Technology. It consists of an ultra-compact RTK-GNSS receiver (positioning terminal) that can be attached to a smartphone or tablet (iPhone/iPad) and a dedicated app, enabling anyone to perform centimeter-level (half-inch accuracy) high-precision positioning and AR display easily with their device. In other words, your everyday smartphone is transformed into a high-precision, all-purpose surveying instrument and AR device—a revolutionary system.

The greatest feature of LRTK is that complicated coordinate-alignment work on site becomes unnecessary. General AR apps required manual adjustments to align 3D models to reference points on site each time, or placement of markers for camera recognition. There was also the issue of the model drifting when users moved, making stable AR display outdoors surprisingly laborious. LRTK, however, continuously uses accurate positioning information from RTK-GNSS to track model positions, so a displayed 3D model remains aligned with the actual survey coordinates without drifting. Once the device is started, design models are projected onto the site in world coordinates immediately, allowing high-precision model display even where vegetation or structures make marker placement difficult. This “AR projection that does not drift” is a unique strength of LRTK and can be achieved by anyone on site with simple procedures.

Moreover, LRTK includes functions to instantly share acquired position information and captured photos/point cloud data on the cloud. This allows survey results taken on site to be shared with the office or remote clients on the spot, enabling real-time feedback for plan revision or approval. For example, by sending a shared URL issued on the LRTK cloud, a client can check the latest site data and AR footage uploaded to the web without logging in. Information-transmission time lags are significantly reduced and the cycle to reach consensus is shortened.

In short, Simple Surveying with LRTK is a concrete solution that embodies the “on-site communication revolution by AR technology” discussed in this article. Without purchasing specialized surveying equipment, attaching a small receiver to your smartphone provides a state-of-the-art surveying and AR experience. Survey tasks and stake-out work that previously relied on skilled craftsmanship can be performed by projecting digital 3D models accurately onto the site with LRTK. Because one smartphone per person can complete tasks from surveying to as-built management and AR-based verification, work time is drastically reduced and productivity soars. Also, since high-precision positioning data and 3D scanning/AR features are integrated, you not only measure but can visually confirm and easily share measured results on the spot. As a result, from sharing the completed image with clients to preventing mistakes and managing progress, on-site DX in civil engineering will accelerate dramatically.

LRTK is compatible with *i-Construction* promoted by the Ministry of Land, Infrastructure, Transport and Tourism and is an ideal solution for promoting digitalization in the construction industry. Please consider it as an opportunity to dramatically improve the accuracy of construction management and communication with cutting-edge AR × positioning technology.

FAQ

Q1. What can AR technology do in civil engineering? A. Using AR (augmented reality), digital design information can be overlaid onto the real construction site through a smartphone or tablet screen. For example, you can project life-size models of structures from the drawings on site and compare as-built conditions with the design, or share the completed image on the spot. You can also display virtual pile-driving positions or lines to guide layout marking (setting-out work). Depending on how AR civil engineering is used, various aspects of site management and surveying become intuitive and efficient. Communication that previously relied on text and drawings can be understood visually via AR, reducing perception gaps among stakeholders.

Q2. Do I need special equipment or skills to use AR on site? A. No. Basically, you can get started with a smartphone or tablet and a compatible AR app. Modern smartphones have high-performance cameras and, in some cases, LiDAR sensors; with a dedicated app anyone can easily perform 3D scanning and AR display. Operation is intuitive—simply move the device according to on-screen guidance to measure or display models. The systems are designed to be usable without special qualifications, and even site staff unfamiliar with IT can learn quickly with short training. If you want a higher-precision AR experience, you can improve accuracy by adding equipment such as an RTK-GNSS receiver (for example, using a system like LRTK can keep positioning errors to a few centimeters). In any case, it is far simpler than traditional surveying equipment, and people from young to experienced can use the technology.

Q3. Can AR share the situation even if the client cannot come to the site? A. Yes. If you share the AR footage or the captured 3D data via the cloud, remote clients and stakeholders can access the latest status. For example, if the site manager uploads photos or point cloud data with the projected completed model to the cloud, the client can access that data from the office and virtually grasp the site situation. Services like the LRTK cloud allow you to send an issued URL so the client can view uploaded AR footage on the web. You can also live-stream AR footage in real time for remote meetings, providing vivid explanations in online conferences. In this way, AR enables “viewing the same thing” in communication, so consensus building with the client can proceed smoothly even remotely.

Q4. What is LRTK? What are its benefits? A. LRTK is a civil-engineering solution that fuses high-precision positioning technology RTK with AR, using a dedicated compact GNSS receiver attached to a smartphone. The brand name originates from the company and concept and is not a specific acronym (it does, however, imply the use of RTK—real-time kinematic positioning technology). The biggest advantage of LRTK is that your smartphone becomes a centimeter-level (half-inch accuracy) surveying device with simple equipment. Without expensive dedicated surveying machines, a smartphone plus a small receiver enables high-precision positioning, 3D scanning, and AR display, dramatically improving efficiency of site surveying and as-built verification. Because positioning data, 3D models, and AR functions are integrated, measured results can be displayed in AR on site for easy confirmation and sharing. As a result, from sharing the completed image with clients to preventing mistakes and quickly reaching consensus, the quality and speed of on-site communication improve significantly. LRTK is an attention-grabbing tool that supports construction DX, and its adoption is expected to increase on-site productivity and reliability.