AR Construction Builds the Worksite of the Future: The New Standard in the Construction Industry

Table of Contents

• Introduction: The new normal brought by AR in construction

• What is AR technology? Why it is attracting attention in the construction industry

• Expanding AR use cases on construction sites

• 5 benefits of AR utilization

• Case studies of AR use in the construction industry

• Challenges of AR adoption and future outlook

• Easy AR use enabled by simple surveying with LRTK

• FAQ

Introduction: The New Normal Brought by AR Construction

In recent years, digital transformation in the construction industry (the so-called construction DX) has been accelerating, and among these trends the use of AR (augmented reality) technology—often called AR construction—is becoming the new normal on construction sites. Tasks that were previously performed with drawings and 2D plans can now be confirmed by overlaying 3D models and information onto the real world through smartphones and tablets, bringing revolutionary changes to construction management, surveying, and inspection. In fact, AR has begun to be piloted and introduced in many construction projects both domestically and internationally, and the idea that "AR will be commonly used on future construction sites" is becoming increasingly realistic.

This article explains the basics of AR technology in the construction industry, its use cases, the benefits of adopting AR, concrete examples, and future prospects. In addition, at the end of the article we introduce simple surveying using "LRTK," a solution that makes AR adoption easy. It offers a preview of the 'new normal' in how AR is transforming worksites.

What is AR technology? Why it is attracting attention in the construction industry

AR (Augmented Reality) is a technology that overlays digital information onto real-world images through devices such as smartphones, tablets, and AR glasses. A familiar example is the game app "Pokémon GO", where virtual characters appear in the real-world scenery seen through the camera, but in the construction industry this technology is used for on-site work support.

The reason AR is attracting attention in the construction industry is that it can intuitively connect the construction site and design data. Traditionally, construction personnel carried out on-site checks while looking at paper drawings or CAD plans, but with AR they can see the finished image from the drawings while standing on site. For example, if you superimpose a life-size 3D model of the planned building over the building under construction as seen through a smartphone, you can confirm the finished appearance on the spot.

AR is often contrasted with VR (virtual reality), but whereas VR is self-contained within a virtual space, AR adds information to the real space. In the construction industry, which deals with "the real site that exists right now," AR that overlays the real scene is more practical for on-site inspections and work support. For these reasons, AR technology is expected to deliver significant benefits in a variety of areas such as design, construction management, and safety measures.

Expanding AR Use Cases on Construction Sites

AR use cases on construction sites are truly diverse. Below we list the main scenarios and introduce how AR is used in each.

• Design and planning stage: Display the completed model of planned buildings and civil structures on the actual site using AR to share design intent with stakeholders and to check impacts on the surrounding landscape. Because the completed image can be experienced on site before construction begins, explanations and consensus-building with clients and neighboring residents become smoother.

• Construction management (quality and progress control): On construction sites, verify structures and equipment by overlaying the design 3D data onto real images. The verification work that used to involve checking drawings becomes an intuitive on-the-spot visual inspection, enabling early detection of construction errors and preventing rework. AR is also used to visualize construction progress and upcoming tasks, facilitating information sharing between the site, the office, and the client.

• Surveying and as-built verification: AR is being applied to surveying tasks that traditionally required skilled craftsmanship. On a smartphone or tablet you can place a virtual survey pole to measure terrain, and overlay design cross-sections with the as-built condition to check consistency. The emergence of AR surveying apps that allow one person to instantly measure terrain and earthwork volumes has rapidly improved surveying efficiency.

• Safety management and equipment inspection: AR helps visualize hazardous areas and make underground utilities “visible.” For example, tools have appeared that let workers simply point a smartphone and display the positions of buried pipes and cables in AR. These are applied to reduce the risk of accidentally damaging buried utilities at excavation sites and to provide safety training through high-altitude work simulations.

• Training and remote support: AR can be used to pass on veteran know-how and train new staff. On site, using AR glasses or tablets to display work procedures and cautions in the field of view enables learning while working. You can also share on-site footage in real time with experts at headquarters and receive instructions and advice across AR from remote locations. This helps maintain work quality while compensating for a shortage of skilled workers.

As described above, from design to construction, maintenance, and training, use cases for AR are expanding across every process. Now, let's take a deeper look at the concrete benefits that the introduction of AR brings to the field.

Five Benefits of Using AR

1. Dramatic Improvement in Work Efficiency (Time Savings and Reduced Manpower)

One of the biggest advantages of introducing AR is that it dramatically improves on-site work efficiency. For example, in cases of surveying and dimensional measurements, tasks that used to take two or more people half a day can be completed by one person in a few minutes with an AR-enabled smartphone app. In fact, with an AR surveying app for iPhone/iPad developed by a major general contractor, by bringing an iPhone to the site and simply placing virtual stakes (poles) on the screen to specify the area, the volume of fill or excavation could be measured instantly and automatically. As a result, it was reported that surveying work time was reduced by more than 90% compared to conventional methods.

In addition, AR also speeds up the on-site verification and inspection process. Until now, as-built inspections required multiple steps—surveying after construction and comparing with drawings…—but if design data can be overlaid onto the actual site with AR and checked on the spot, immediate decisions can be made. Furthermore, overseas cases report that by directly displaying 3D design models in AR and omitting the process of redrawing them into 2D drawings, they reduced overall project costs by about 10%. In other words, using AR significantly saves labor and time, directly leading to shorter schedules and cost reductions.

2. Reduction of Errors and Rework (Improving Quality)

One of the frequent issues on construction sites is construction mistakes and the rework that accompanies them. Many causes stem from positional deviations and dimensional errors. AR can be a powerful tool to prevent this. For example, if the designed locations of piping and rebar are displayed in AR over a tablet’s camera view, you can intuitively check for clashes or incorrect installations before construction. At Shimizu Corporation, they introduced the AR system "Shimz AR Eye" for equipment piping work during construction and, by overlaying BIM piping models onto site footage, made it possible to verify discrepancies between drawing information and the actual installation on the spot. As a result, compared to when checks were performed with paper drawings, the burden of verification work was greatly reduced, and it has been reported to have led to a reduction in human error.

Additionally, some AR services offer the capability to display underground buried pipes and buried objects in AR without excavating them. This allows the precise locations of underground infrastructure to be known in advance, preventing unexpected collisions or damage during excavation and protecting construction quality. By using AR to constantly visualize "the gap between design and the site" and correct it early, rework can be reduced and quality defects prevented before they occur.

3. Facilitating communication (sharing among stakeholders)

AR brings innovation to on-site communication. Construction projects involve many stakeholders—designers, construction managers, tradespeople, and clients—but sharing a common vision with AR can eliminate gaps in understanding. For example, if you explain while displaying the planned building at full scale in AR on a tablet (displaying the planned building at full scale in AR), the completed image that was difficult to convey with paper drawings becomes clear at a glance. Using AR in presentations to clients or owners can prevent mismatches like "this isn't what I expected" in advance and enable consensus-building with a stronger sense of agreement.

Even on site, if you display the next steps and cautions on AR, you can reduce mismatches in understanding between veteran and less experienced staff. As the saying goes, a picture is worth a thousand words, and visually showing via AR speeds comprehension compared with instructions given only in words. Furthermore, remote support can be realized in which engineers at headquarters share the on-site AR footage and give instructions in real time. This allows the expertise of experienced personnel to be applied to on-site work even when they are not physically present, while also reducing time lost to travel. By making information sharing smoother, a virtuous cycle is created in which smoother information sharing leads to error prevention and improved safety.

4. Improving Safety (Risk Visualization and Training)

AR is also effective for safety management on construction sites. There are various risk factors on site, such as working at heights, heavy equipment operations, and the presence of underground utilities, but by visualizing them with AR it becomes easier to anticipate hazards and take countermeasures. For example, in pre-work safety training, VR/AR technologies can be used to simulate the risk of falling from heights, or AR can be used to highlight hazardous areas on site to ensure thorough awareness. Also, during actual work, if AR can display information on site such as "No entry beyond this point" and "High-voltage lines run behind this wall", it can raise each worker's safety awareness.

The aforementioned AR visualization of underground buried pipes also has major safety benefits. During excavation work, the confirmation that traditionally relied on drawings and guesswork — “there should be a gas pipe around here” — could, if AR can accurately display the pipe’s route on the actual ground, prevent accidents that would accidentally damage piping. Furthermore, if an accident does occur, AR is useful for on-site investigation and reporting. By overlaying AR information on site photographs and recording them, the situation can be reviewed in a three-dimensional, visual way, which can be used when considering measures to prevent recurrence.

5. Support for Human Resource Development and Technical Succession

With concerns about the aging of skilled workers and a shortage of young personnel, AR also contributes to on-site personnel development. For new employees and young technicians, it is difficult to understand complex structures and processes from paper drawings alone, but by working while viewing life-size models or animated procedures in AR, they can learn intuitively. For example, if they wear AR-enabled smart glasses while working, even with both hands occupied the next work instructions and checkpoints are displayed in their field of view. Because they can proceed as if someone were teaching them beside them even without an instructor present, on-site OJT can be streamlined.

AR is also effective for the visualization of veteran craftsmanship. The subtle hunches and tacit knowledge acquired during work are hard to convey in words, but by displaying auxiliary lines and guides with AR and providing on-the-spot feedback on the quality of work, it supports the transmission of skills. In fact, there have been reports that using AR manuals in equipment maintenance "dramatically reduced forgotten bolt tightening and missed inspections." This is a good example of AR complementing human attention with technology, such as highlighting bolts that were forgotten to be tightened. Overall, AR demonstrates value from a human-resources perspective as a tool that reduces mistakes by less-experienced workers, accelerates their development, and eases the burden on skilled workers.

Challenges in AR Adoption and Future Prospects

While expectations for AR in construction are rising, several issues have been identified regarding its full-scale deployment on-site. Here, we outline the current challenges and future prospects.

1. Device and equipment challenges: Currently, the AR devices mainly used on construction sites are smartphones and tablets. While these are convenient and low-cost, they are unsuitable for prolonged use or tasks that require both hands. Helmet-integrated AR glasses (smart glasses) and devices like HoloLens are also being trialed, but they are expensive and have issues with weight and field of view, so they still face hurdles for everyday use. However, technology is advancing rapidly, and it is expected that within the next few years lighter, higher-performance, and more affordable AR glasses will emerge. This will make the prospect of a future site where "all workers wear AR goggles" increasingly realistic.

2. Accuracy and alignment: The accuracy of AR displays has also been a challenge. In typical smartphone AR, position estimation relies on GPS and gyros, which can cause errors on the order of several tens of centimeters (several tens of in) and a drift phenomenon in which the model shifts when the user moves. In construction use cases, millimeter- and centimeter-level accuracy (millimeter-level ≈ 0.04 in, centimeter-level ≈ 0.4 in) is often required, and some have asked, "Is precise positioning impossible with AR?" However, this too has advanced. With AR combined with high-precision GNSS (RTK), discussed later, and image-analysis–based position correction techniques, it is now possible to fix a 3D model in the real world without deviations at the level of a few centimeters (a few in). In other words, the accuracy hurdle is steadily being overcome.

3. Data preparation and operation: AR utilization basically requires digital 3D data. Without assets such as BIM/CIM models or point cloud data, nothing can be displayed. While BIM use is advancing in large companies’ major projects, small- to medium-scale works and renovation projects often lack 3D data, making it difficult to reap the benefits of AR. However, in recent years tools have appeared that can easily 3D-ify sites using photogrammetry or scanners, and tools that semi-automatically generate 3D models from 2D drawings are also emerging. In extreme cases there are even simple features for improvised AR display that let you point a smartphone on site, measure only the necessary points, and display AR on the spot. In other words, even without a full BIM model, it has become possible to create data on-site and use AR. There is also concern on the operational side about whether people who are not used to IT on site can use these tools. On this point, companies that actually introduced AR tools have reported that “thanks to intuitive operation, site staff were able to start using them without special prior training.” UI improvements and simple designs tailored to site needs have progressed, increasing the number of products that can be used regardless of IT literacy.

4. Costs and ROI: Introducing new technology involves costs, but in the case of AR one attractive point is that it can be started at a relatively low cost. Smartphones and tablets are already brought to many sites, and free or low-cost AR apps exist. Even when introducing dedicated equipment, in many cases it is less expensive than traditional surveying instruments or advanced specialized equipment, and it is easier to obtain effects commensurate with the investment (ROI). As mentioned above, the cost reductions from shortened work time and reduced mistakes are very large, so AR implementation costs can be fully recovered. Also, subsidies may be available as part of on-site DX budgets. Overall, it is expected that there will increasingly be situations where “not introducing AR and continuing with the inefficient traditional methods” will actually lead to greater losses.

Although the above challenges remain, they are being steadily resolved through technological advances and ingenuity. Above all, the very fact that practical examples of AR in construction are increasing to meet on-site needs of "it would be convenient if it were like this" signals momentum across the entire industry. In the future, AR will fuse with related technologies (AI-based image recognition, IoT sensor integration, etc.), making increasingly advanced applications possible. For example, AI automatically inspecting simply by pointing on site using AR, and sharing construction data in real time via the cloud and reflecting it on everyone's AR screens may also become a reality.

In future construction sites, AR will be as commonplace a tool as air──this is the new normal that 'AR construction' brings. With companies across the industry competing to adopt AR, it's important to start using it now so you don't fall behind.

Easy AR Use Enabled by Simple Surveying with LRTK

Finally, as one solution that allows such AR applications to be easily implemented on site, we introduce "LRTK". LRTK was developed by Refixia, a Minato-ku, Tokyo-based startup, and is a tool that enables centimeter-level high-precision positioning (cm level accuracy (half-inch accuracy)), 3D scanning, and AR display on iPhone and iPad. LRTK solves the on-site alignment (origin alignment) and display drift issues that have been challenges for conventional AR by using the RTK method of GNSS (Global Navigation Satellite System).

Specifically, a pocket-sized dedicated RTK-GNSS receiver is attached to an iPhone for use. Because this receiver constantly acquires a highly accurate current position and compares it in real time with the coordinates of the model displayed in AR, the digital model is always precisely fixed in its "proper place." This enables a stable AR display in which the model does not shift even when the user walks around, and a major feature is that 3D data can be overlaid in the correct position without performing complicated reference-setting work on site.

Furthermore, the LRTK is designed as an all-in-one simple surveying instrument that can handle a variety of on-site tasks with a single unit. Leveraging high-precision positioning information, it can perform a point-cloud scan of terrain (using the iPhone's LiDAR sensor) at the press of a button, and measure distance, area, and volume on the acquired point cloud. For example, if you scan piping before it is buried with an iPhone+LRTK and save it to the cloud, you can, even after backfilling, confirm its position and depth as if viewing through AR, which can be useful for future excavation work. Surveying data and photos are automatically synced to the cloud, making real-time information sharing between the field and the office another attractive feature.

Operation is extremely simple and can be handled intuitively even without specialized knowledge. On actual sites, there have been comments such as "I could use it immediately without prior training", and from seasoned workers to younger staff everyone can leverage AR with a smartphone-like feel. Compared with conventional surveying equipment, equipment costs are also reduced, making it a practical solution that site supervisors and foremen can carry one per person and use whenever they want.

With LRTK, you can immediately experience on your own job site the benefits of AR construction introduced so far. Efficiency through high-precision simplified surveying, error prevention with drift-free AR, and information sharing via cloud integration — you can achieve all of this on your smartphone without any special large-scale system. It is truly a tool that brings the "job site of the future" to the present. If you are interested in AR construction, please take a look at LRTK's detailed information and consider implementing it on your job site.

FAQ

Q. What is the difference between AR and VR? Which should be introduced in the construction industry? A. AR (augmented reality) is a technology that overlays digital information onto real-world scenes, while VR (virtual reality) is a technology that provides experiences entirely within a virtual environment. In the construction industry, AR, which can be used while viewing the actual site, is more suitable for construction management and surveying. On the other hand, VR is suited to safety-training simulations and design reviews in virtual space. The two are used according to their purposes, but in terms of supporting on-site work, AR is becoming the "new normal."

Q. What equipment and environment are required to use AR on-site? A. Basically, you can get started with a device that supports AR display such as a smartphone or tablet. Recent smartphones have robust AR capabilities and can be used simply by installing a dedicated app. If you want to view on a larger screen, a tablet like an iPad is effective. Also, on bright outdoor sites, consider screen visibility. In addition, if you want to improve accuracy, using attachments such as RTK-GNSS receivers can provide AR with minimal positional drift (for example, there are solutions like LRTK). As for network environment, communication is required when linking to the cloud or sharing among multiple people, but many apps allow basic AR display to work offline.

Q. I'm worried about accuracy with smartphone AR. Can it also verify positions to the millimeter level (mm (0.04 in))? A. With a standard smartphone-only AR, GPS errors and sensor errors can cause deviations on the order of tens of centimeters (tens of cm; several inches to a few feet). However, with appropriate techniques it's possible to achieve quite high-precision AR display. For example, indoors, markerless AR that recognizes walls and floors to align references can provide stable displays. Also, when high accuracy is required outdoors, combining the aforementioned RTK-GNSS can achieve accuracy within several centimeters (within several cm; within a few inches). In practice, there are reports of using AR technology to verify bridge-pier installation positions to the centimeter level (cm (0.4 in)) and to measure ground inclination to the millimeter level (mm (0.04 in)). In other words, with appropriate equipment and methods, precise position verification with AR is fully possible.

Q. Can veteran on-site workers handle AR? Many are not familiar with IT... A. Yes, because many AR apps are designed for intuitive operation, even those who are not familiar with IT can use them relatively smoothly. You only need to hold up the screen as if taking a photo with a smartphone, so no complicated operations are necessary. In companies that have actually introduced AR solutions, there were concerns such as "older craftsmen might avoid it at first," but when they tried it, there are examples of it being well received with comments like "You can tell right away" "It's convenient." Also, there is no need to read a lot of text, and you can understand just by looking at the 3D models and markings displayed on the screen, so it can actually be easier for workers who lack confidence in reading language or drawings to make use of it. If you provide a brief explanation of how to operate it at the time of introduction, it should be accepted across age groups.

Q. I'm worried about the costs of implementing AR. Is there really an effect that justifies the cost? A. The cost of implementing AR depends on the case, but in most situations you can start at low cost if you limit its use to smartphones and tablets. Even when introducing paid specialized apps or devices, they are relatively inexpensive compared with traditional large equipment. Above all, considering the labor and rework costs that AR can reduce, the return on investment can be high. For example, if a surveying task that used to take two people one day can be completed by one person in one hour, that difference quickly translates into cost savings, and avoiding even a single construction error can prevent losses of hundreds of thousands of yen or more. The benefits may be hard to see before implementation, but in practice many sites feel “I wish we had used it sooner” after implementation. Also, there are cases where national or local government subsidies and grants can be used, so if you are concerned about costs it is a good idea to consult a specialized vendor.

Q. We’d like to introduce AR at our job sites—where should we start? A. As a first step, we recommend experiencing AR with a simple app you can try on your own smartphone or tablet: try a simple AR app that can be used on your existing smartphone or tablet. For example, try measuring distance or area with a free AR measurement app, or get a feel for it with a tool that can display simplified architectural models in AR. If you decide to integrate it into your operations seriously, it’s reassuring to contact companies that provide construction-focused AR solutions (for example: LRTK) and request demos or trials. Clarify which of your operations is likely to benefit (surveying, construction management, or inspection), and pilot it at small sites or on specific processes to start. Gradually expand the scope while monitoring site staff reactions, and by rolling out successful examples internally, you can smoothly embed AR-based construction practices as a new norm within your company.