Say Goodbye to Paper Drawings with BIM! The Smart Construction Revolution Enabled by LRTK

Large-format paper drawings spread out on construction sites—long the backbone of site management—are now facing a major shift. The construction industry is burdened with chronic labor shortages, rising infrastructure maintenance costs, and the need for rapid disaster response, making productivity improvements urgent. To address these challenges, the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) is promoting digitalization in construction through initiatives like “i-Construction” and construction DX (digital transformation), with BIM at the center. In fact, BIM/CIM has been positioned by MLIT as the “engine of the productivity revolution,” intended to enhance every business process. Adopting BIM also contributes to workplace reform on site as well as improvements in quality and safety, giving it significant social value. Digital-driven operational efficiency and labor-saving measures are now unavoidable, and BIM holds the key.

Following this trend, from fiscal 2023 the MLIT made BIM/CIM use the default for all directly managed design and construction projects (using 3D models unless there are special circumstances). Furthermore, full mandatory implementation of BIM/CIM for public works is planned by 2027, and adoption is already advancing across public projects worth about ¥2.5 trillion annually. The construction industry is at a major turning point, and full-scale BIM adoption is imperative.

With BIM’s spread, the long-standing reliance on paper drawings is shifting toward digital-data–centric smart construction. This article unpacks what BIM is, its benefits, and real-world site applications, explaining next-generation construction methods that allow you to “say goodbye to paper drawings.” We also touch on LRTK, a high-precision positioning solution that links BIM and the field in real time, and introduce the frontline of the smart construction revolution where anyone can perform high-precision surveying easily.

What is BIM? The shift from paper drawings to 3D data

BIM (Building Information Modeling) is a method that consolidates construction project information into digital 3D models for practical use. Originally developed in the building sector, the concept has expanded into civil infrastructure (CIM: Construction Information Modeling), and today it is commonly referred to as BIM across both architecture and civil engineering. The goal is to centralize and share 3D models and associated information across all phases—from survey and design to construction and maintenance—to improve overall project efficiency.

A BIM model can store not only a 3D model representing the shape, dimensions, and spatial relationships of structures, but also attribute information such as material, strength, cost, and construction dates for each component, and reference information like drawings, photos, point cloud survey data, and reports. Digitally integrating information that used to be scattered across 2D drawings and paper documents allows both clients and contractors to make effective use of the data and boost productivity. Structural and dimensional relationships that were hard to grasp from paper drawings become intuitively visualized in 3D models, deepening shared understanding among stakeholders and reducing miscommunication and errors. As a result, rework caused by design mistakes and on-site corrections are reduced, contributing to improved quality and safety.

BIM essentially forms the foundation of a digital twin—a virtual counterpart of the real structure or site. Advanced examples, such as the Shuri Castle reconstruction, have used BIM-based “digital twin models” to facilitate information sharing among stakeholders. BIM makes it possible to digitalize entire physical spaces at a scale previously impossible with paper drawings, enabling visualization and optimization of the whole project.

Benefits of using BIM (consensus building, quality improvement, labor savings, etc.)

• Consensus building and error reduction through 3D visualization: Structures that are hard to imagine from 2D drawings can be intuitively understood via 3D models. Sharing 3D models at local briefings or progress meetings gives all stakeholders a common vision of the finished product, smoothing consensus and decision-making. Performing clash checks and other verifications on the model during design can reveal mistakes that would be missed on drawings, reducing rework during construction. Consequently, high-quality construction can be achieved with fewer people and shorter schedules, improving overall productivity.

• Progress sharing and improved safety: During construction, the 3D models created at the design stage can be used to simulate and share construction sequences on site. When all staff can visually grasp the finished state beforehand, task planning becomes easier and safety management improves. For instance, complex structures can be understood by checking construction steps via 3D-model animations, helping even inexperienced workers follow workflows. Many sites report positive effects from using BIM models for sharing finished-image expectations and verifying procedures.

• Efficiency in maintenance and management: BIM data also proves powerful in maintenance phases. Recording inspection results on a 3D model for bridges or tunnels lets you centralize crack locations and repair histories. Marking anomalies on the model and linking coordinates, photos, and record dates makes it easy to locate the same spot during the next inspection, aiding degradation tracking and repair planning. Because a BIM model can hold all sorts of attribute data (dimensions, materials, construction date, asset IDs, etc.), the need to reconcile ledgers and drawings disappears, drastically improving maintenance workflow efficiency. This leads to reduced life-cycle costs and longer infrastructure lifespan.

• Shorter schedules and cost reductions: Detailed front-loading in the design stage and concurrent engineering reduce overall schedules and costs. MLIT surveys report many BIM-adopting companies experiencing improved efficiency, faster consensus building, fewer errors, and better safety. Very few firms reported no measurable benefits, so the advantages of BIM are being realized across most sites.

Examples of BIM use: Digital construction advancing on sites

• Large-scale civil works (earthworks, roads, etc.): In earthworks, it has become common to overlay drone-acquired pre-construction 3D point clouds (scan data) with the designed final ground model to precisely quantify excavation and fill volumes. This enhances as-built accuracy control and quality assurance. In road and tunnel works, point cloud terrain data can automatically generate longitudinal and cross sections, enabling comparisons between design models and construction results for quality control. Drone + CIM adoption allows broad terrain capture and immediate earthwork volume calculations that were previously difficult, dramatically optimizing construction planning and progress management.

• Bridges: BIM is also used in bridge projects. 3D models of piers and girders are used to check for interference with surrounding terrain and existing structures and to animate construction sequences for planning. Recently, 3D technology has been applied to bridge maintenance as well: drones scan entire bridges to create detailed point-cloud models for identifying and recording deterioration. Areas like the underside of girders, which previously required high-access platforms for close inspection, can now be examined for fine cracks on point-cloud models, offering an efficient and comprehensive maintenance approach.

• ICT earthworks (smart construction): MLIT-promoted ICT construction (smart construction) integrates ICT into surveying, design, and construction to advance civil works. Practically, 3D design data loaded into construction machines enables machine control (MC) and machine guidance (MG) for automated or semi-automated operation of bulldozers and excavators, allowing precise grading and excavation to the design model. This makes it possible to achieve consistent quality without highly experienced operators, and one supervisor can remotely operate multiple machines. As-built management commonly uses point clouds from drones or 3D laser scanners to compare terrain before and after operations. In one site, drone surveying reduced survey time to less than one-fifth of previous durations and eliminated the need for high-access work, improving safety. ICT construction is advanced together with BIM-driven 3D data use and forms a core technology supporting construction DX.

From these examples, it’s clear that combining BIM with cutting-edge technologies is driving a productivity revolution on site. Combining 3D models with drones and automated machinery can shorten surveying and construction management tasks that used to take days down to hours, and enable precise tasks that were difficult by manual labor to be performed accurately and safely. In practice, the 3D models created with BIM are becoming the digital work instructions on site, and surveying → design → construction → inspection processes are beginning to connect seamlessly. Data-driven smart construction is becoming the new standard.

Paperless site management enabled by data integration

To maximize BIM’s value, close integration between field data acquisition and the design/construction process is essential. The true value emerges when surveying → design → construction → inspection are seamlessly connected by digital data rather than remaining fragmented.

Concretely, the initial stage involves acquiring detailed 3D survey data (point clouds and orthoimages) via drone surveying or ground LiDAR and integrating them as baseline information for terrain and structures into the design BIM model. The resulting high-precision design 3D model can be used directly as machine-guidance data or construction management materials during construction. If you perform as-built surveys during construction, current point clouds and survey coordinates can be immediately reflected in the BIM model to visualize and verify progress. Connecting this workflow end-to-end with digital data eliminates reliance on paper drawings and manual information transfer, realizing paperless construction management.

A key to data integration is using a common coordinate system and data formats so that “measured data goes straight into the model, and model data goes straight to the field.” MLIT recommends open data formats like LandXML, J-LandXML, and IFC for BIM application in public works. This enables surveying instruments, design CAD, and construction machines to use the same data, reducing double entry and rework. For example, whereas crews used to read paper drawings and manually input coordinate values into survey instruments on site, they can now simply load electronic data into equipment. For post-construction verification, design models and measured point clouds can be overlaid and differences automatically color-coded so areas needing additional work are immediately apparent.

Recent cloud advancements have made data sharing between site and office even more real time. If site-measured coordinates or photos are synced to the cloud, headquarters or design teams can view the data instantly and issue instructions. Previously, there was a time lag while survey teams returned to the office to create drawings, report, and start reviews; cloud integration now enables the speedy practice of “measure, show, transmit, and decide.” This accelerates overall planning and contributes to schedule reductions and cost savings. Remote construction management, where experts monitor from afar, is becoming practical, reducing travel time and the need for hazardous on-site work and thereby improving safety.

Thus, establishing an environment where surveying → design → construction → inspection data flows smoothly is key to BIM-driven efficiency gains. Conversely, no matter how sophisticated the 3D model, its value is lost if data exchange with the field is fragmented. The next section delves deeper into LRTK, a technology that links the field and models and embodies smart construction.

What is LRTK: An ultra-high-precision positioning tool you can use with a smartphone

One foundational technology supporting advanced BIM use is RTK (Real-Time Kinematic) positioning. RTK exchanges GNSS data received at both a base station and a rover via communication to cancel out error factors and achieve centimeter-level positioning accuracy. While normal GPS has errors on the order of 5–10 meters, RTK can provide centimeter-level accuracy in real time. Since the 1990s, RTK has gradually been applied to civil surveying and machine positioning, but traditional RTK equipment tended to be large, expensive, and required specialist knowledge. Deploying a fixed receiver and radio equipment, carrying tripods as a two-person team to set up—a high hurdle for small contractors and municipalities. Poor communication environments prevent positioning, and satellite signal blockage in forests or high-rise areas reduces accuracy.

Solving these issues, an innovative device that makes RTK surveying easy for anyone is LRTK (Local RTK). LRTK refers to a positioning solution centered on ultra-compact RTK-GNSS receivers that attach to smartphones or tablets. For example, the LRTK Phone is a product that attaches to an iPhone; weighing about 165 g and about 1 cm thick, it sticks to the back of a smartphone and instantly transforms a daily-use phone into a surveying instrument with centimeter-level accuracy. Tasks that previously required two people and a tripod can now be completed by one person with just a smartphone—truly opening the era of “surveying with a smartphone.”

LRTK operation is very intuitive. Launch the dedicated app, and it connects to the device automatically so high-precision positioning begins within seconds. No complex initial setup or special controller is needed, and anyone familiar with smartphones can quickly learn to use it. The interface allows you to record points you want to measure with a tap or follow on-screen guidance to navigate to target points, offering a game-like experience with minimal training costs. Compared to traditional surveying instruments that only trained technicians could operate, this is a significant leap.

LRTK leverages the latest technology in both hardware and software. The device contains a battery that runs about six hours and supports extended operation via a mobile battery. Regarding communications, in areas without cellular coverage such as mountain regions, it can directly receive centimeter-level augmentation services provided by Japan’s quasi-zenith satellite system Michibiki (QZSS) to correct errors, enabling centimeter-level positioning even outside cellular networks (in covered areas it also supports network RTK via the internet). This greatly improves the traditional RTK requirement for constant internet connectivity.

Its biggest advantage is rich functionality enabled by the smartphone platform. The LRTK app integrates with a phone’s built-in LiDAR sensor and camera to perform high-precision 3D scanning on site. Acquired point clouds are immediately tagged with global geodetic coordinates, eliminating the post-scan registration step previously required. It can AR-display design 3D models over the phone’s camera image so models align accurately with real-world views. The positioned photo feature automatically tags captured photos with precise latitude/longitude and camera orientation, making it easy to locate the exact same crack or repair spot later. Other features—such as coordinate navigation that guides you to a specified coordinate with an arrow (for stake-out guidance) and length/volume measurement on captured point clouds—bring tasks that once required multiple specialized devices and software into an all-in-one LRTK + smartphone workflow. That such capabilities are available without expensive specialized equipment is remarkable, giving every field worker the potential to use them.

In short, LRTK is a high-precision GNSS positioning device you can use with a smartphone. It dramatically simplifies field surveying and leads to smart construction that links BIM models and the real world in real time.

The smart construction revolution LRTK makes possible

Introducing LRTK to a site transforms surveying and construction management methods. The biggest point is that it directly links digital BIM models with the real site.

For example, using LRTK you can reference the 3D model created in the design phase right on site. If you AR-project the design model onto the real scene via the smartphone screen, you can share the completion image that was difficult to understand from paper drawings on the spot and intuitively grasp “what will be built here.” Because all stakeholders can simultaneously view the same finished image, misunderstandings about construction content decrease and communication improves. AR-guided positioning enables accurate placement of structures at specified locations and heights and pinpoint guidance for stake-out positions, greatly streamlining layout work and reducing human error. One site reported that using LRTK’s AR navigation for stake-out reduced a task that used to take half a day to a short duration with far fewer mistakes. LRTK thus directly provides on-site guidance that tells workers “construct this exactly as shown” by linking the digital model to the physical space.

Conversely, feedback from the field to digital models becomes real-time. Coordinates measured with LRTK and acquired point clouds can be immediately shared via the cloud, enabling instant incorporation of the latest site data into BIM models for office-side review and analysis. For example, scanning the post-excavation terrain with LRTK and comparing it to the design model lets you verify as-built conditions on the model and immediately judge surplus or deficit. Previously, quantity calculations and as-built checks weren’t possible until data were brought back; now you can compute and assess quantities on site. On the LRTK cloud, shared point clouds can automatically generate cross sections, and stakeholders can be given URLs to view 3D models in a browser. Without specialized software, results can be reviewed, making site–office coordination much smoother and enabling real-time construction management practices of “measure, show, transmit, and make the next decision.”

Because LRTK combines GNSS positioning with smartphone sensor technology, it supports seamless position measurement outdoors and indoors, further promoting smart construction. Other GNSS devices lose positioning when satellite signals are blocked, but LRTK can supplement positioning with an iPhone’s AR technology, allowing brief periods of self-positioning under bridges or in forests so measurements can continue. Even when satellites cannot be fully captured, camera imagery and inertial sensors can maintain positioning, filling previous gaps such as “stopping until you get back outside a tunnel” and making LRTK a true “measure anywhere” tool. This feature is powerful for tunnel work, indoor tasks, and urban surveys.

Thus, adopting LRTK on site enables real-time, two-way linkage between BIM models and the field, making surveying and construction management smart. By presenting high-precision digital models on site for error-free construction and immediately measuring and reflecting as-built conditions into models, projects can proceed with data that is always current and consistent. This is the ideal of smart construction, and LRTK is making it a reality.

Future outlook: BIM guiding the future of construction DX

Digital transformation (DX) in construction will accelerate further. In the context of infrastructure DX, BIM will become the core integrating IoT, AI, and robotics to more tightly unify design, construction, and maintenance processes. The long-term vision includes building a constant “digital twin” of the site to monitor and control conditions in real time.

Automation and labor-saving initiatives are already producing advanced cases. In building construction, painting robots and rebar-assembly robots for interior finishing are being commercialized, reporting worktime reductions of 30–50%. In civil engineering, automated heavy-equipment control and remote operation are spreading, with trials where one operator oversees multiple machines. Stable quality can be maintained without relying solely on experienced operators, enabling newcomers to perform at a consistent level and easing training burdens. Autonomous patrol robots and AI surveillance cameras are beginning to enable unmanned nighttime security and real-time safety checks. Drones are indispensable for surveying and progress management, automatically generating 3D models from aerial photos to calculate volumes and monitor as-built conditions, making high-altitude surveys without scaffolding common and improving safety while greatly reducing work time (reports of less than one-fifth the previous time exist).

This trend of automating and assisting human tasks with digital technologies is the essence of labor saving. It doesn’t merely reduce personnel; it lets machines handle precision or dangerous tasks so people can focus on more creative work. Adopting labor-saving technologies is expected to deliver societal benefits in productivity, safety, and quality control.

The future vision for BIM and smart construction is a fully data-driven feedback-controlled workflow: continuously visualizing the site digitally and autonomously advancing construction. AI-based automatic terrain recognition, automatic 3D model generation from point clouds, and high-speed cloud communication for remote coordinated work will increase operational convenience and efficiency. MLIT’s “i-Construction 2.0” promotes site automation aiming for fundamental labor reductions—such as one person controlling multiple machines and automating design through construction. In the future, one site supervisor might monitor multiple robots and machines while people concentrate on decision-making and creative tasks.

High-precision digital data is a prerequisite for this future. No matter how advanced AI or robots become, inaccurate base drawings or survey data will prevent correct operation. The fusion of BIM models and field measurement technologies—tools like LRTK—will play a major role. If “anyone can measure accurately,” digital management can reach every corner of the site and amplify DX benefits. LRTK’s spread of smartphone-based surveying could help solve chronic technician shortages: intuitive operation lowers training costs and enables newcomers to use it quickly, reducing dependency on veterans and easing skill transfer. LRTK’s easy, high-precision positioning is therefore a potent enabler of MLIT-promoted initiatives like i-Construction and wider construction DX. As smartphone-based surveying methods expand, we can expect major transformations in surveying, construction practices, and site workstyles.

Conclusion: Experience easy surveying with LRTK

We hope you’ve grasped the value LRTK brings to BIM and smart construction. Finally, here’s a quick review of how simple smartphone surveying with LRTK can be.

• Setup: Attach the LRTK device to the back of your smartphone (e.g., an iPhone) and launch the dedicated app. There is an initial user registration, but once connected you’ll have automatic device pairing on subsequent uses and positioning starts within seconds.

• Preparing for positioning: The app acquires satellites and begins receiving correction data. In roughly 30 seconds the fix solution stabilizes, and the screen displays a high-precision mode status such as “Centimeter-level accuracy available.” This indicates you’re ready to survey.

• Measuring points: At the target point, hold the phone steady and tap the app’s “Point positioning” button. After several seconds of observation, an averaged high-precision coordinate is calculated and the latitude, longitude, and elevation appear on screen. You can add a point name or notes and save the record. It’s literally one tap to obtain an accurate location.

• Photo documentation (optional): To record site conditions with photos, switch to “positioned photo” mode and take pictures. The photo files are automatically tagged with precise latitude/longitude and camera orientation, allowing later verification against cloud maps and supporting report creation and time-based comparisons.

• Stake-out and guidance (optional): For staking coordinates from drawings, use the “coordinate navigation” function. Enter the target coordinates and the on-screen arrow shows the direction while distance updates in real time. Follow the guidance until the arrow turns green, indicating arrival at the target; place a stake or marker to complete accurate layout even without surveying expertise.

• Data sharing: After surveying, tap the app’s “Sync” button to upload data to the cloud. Measured coordinates, photos, and point clouds are saved in the cloud and can be immediately accessed from office PCs. You can issue shareable URLs for stakeholders to view 3D data in a browser and measure distances or areas. This makes it possible to measure on site and instantly share accurate results for subsequent tasks in a one-stop flow.

With LRTK, centimeter-level surveying that used to rely on skilled technicians becomes surprisingly simple. With just a smartphone, anyone can achieve cm-level accuracy. LRTK’s combination of ease and precision makes it a powerful tool for advancing BIM-based smart construction. Try LRTK surveying on site—you’ll likely experience efficiency gains and peace of mind that overturn conventional thinking. Embrace the new form of construction LRTK enables and take your site to the next stage.