Coordinate Navigation Revolutionizes Piling! Easy 3D Construction Enabled by LRTK

Introduction: The Current State of 3D Construction and Piling Work

In recent years, the construction industry has been paying increasing attention to 3D construction, a method that leverages three-dimensional data. By using digital 3D models and coordinate data from the design stage and directly referencing them on site, the goal is to improve productivity and accuracy. In reality, however, basic positioning tasks such as piling (stakeout/pile-driving) work still often rely on traditional methods at many sites.

In typical piling work, surveyors or site staff determine positions—"drive a pile at this point"—based on 2D drawings, and mark the ground with stakes or markers. A common method uses a total station (optical surveying instrument), setting up the device and measuring angles and distances from a reference point to determine each pile location. This work usually requires at least two people, and placing many piles across a wide site demands significant effort and time. Operating surveying instruments requires specialized knowledge and experience, and amid a growing shortage of skilled workers and manpower, piling work can become a bottleneck.

Outdoor work also faces issues such as difficult instrument setup due to bad weather or terrain, or obstructed lines of sight that delay positioning. Manual positioning carries inevitable risks of measurement errors and marking mistakes, and even a few centimeters of misplacement can affect later construction quality. Therefore, traditional piling required experienced staff to proceed carefully with repeated checks. Despite the concept of 3D construction, efficiency at the actual piling stage was limited.

What Is Coordinate Navigation? Definition and Functions

A new approach called "coordinate navigation" has emerged as a key to changing this situation. As the name implies, coordinate navigation refers to the technology or function that guides people or machines to a specific coordinate point. If the target point’s coordinates (latitude, longitude, elevation, etc.) are known in advance, GNSS (Global Navigation Satellite Systems) and similar systems can be used to navigate a worker to that location. Think of it as an on-site car navigation system. Just as a car's navigation guides a driver to a destination address, coordinate navigation leads the user directly to the target coordinates without getting lost.

The basic mechanism of coordinate navigation is simple. When you input (or select) the target coordinates into a device, the device displays in real time the direction to move and the remaining distance. The worker simply walks in the direction indicated by the on-screen arrow and can instantly tell whether they are approaching or moving away from the target. At longer distances the display shows the "approximate bearing and distance," and as you get closer it shifts to finer distance and direction guidance, ultimately indicating "you are at the target!" when you arrive.

This idea of coordinate guidance is powerful if sufficient accuracy can be achieved. Even without staring at plans or tape measures, anyone can reach the exact point via intuitive navigation. However, realizing this required positioning technology capable of centimeter-level accuracy. That’s where the smartphone-based high-precision positioning solution "LRTK" was developed. LRTK uses a compact RTK-GNSS receiver attached to a smartphone to enable centimeter-class positioning and offers an all-in-one field tool through an app that provides coordinate navigation among other functions. The next section examines the flow and features of coordinate guidance using LRTK in detail.

Workflow and Features of Coordinate Guidance with LRTK

Using LRTK’s coordinate navigation function makes guiding to piling positions remarkably simple. Below is the typical usage flow.

• Prepare coordinate data: Before construction, register the design coordinate list for points requiring piles or placements in LRTK’s cloud system. Each point can be managed with a name or ID, allowing hundreds of coordinates to be organized even on large sites. On site, simply select the desired point from the LRTK app on your smartphone to set that coordinate as the navigation target.

• Start navigation: Once the target coordinate is set, the smartphone screen displays a directional arrow and the straight-line distance to the target, and navigation begins. For example, the screen may show "NE 5.3m," so you walk northeast as instructed. LRTK continuously updates your position using high-precision GNSS positioning, so the distance decreases as you walk and the direction is adjusted in real time.

• Precision guidance and arrival confirmation: As you approach the target, the display automatically switches to a finer guidance mode. It guides you in increments such as "20 cm left" or "10 cm left" until the remaining error reaches zero. When you finally coincide with the target point, the on-screen marker aligns exactly and an alert or notification confirms arrival. Guidance to the specified coordinate is now complete. You can then drive the pile or mark the point, and the positioning task is finished.

As this flow shows, LRTK’s coordinate guidance can be completed via simple button operations and on-screen instructions, even without specialized knowledge. There is no need to remeasure dimensions on site or set up instruments to measure angles. A single worker can reach the target point with just a smartphone in hand.

A notable advantage of LRTK’s coordinate navigation is the combination of high accuracy and ease of use. RTK-GNSS positioning keeps horizontal errors to a few centimeters and vertical errors to a similar order, enabling positioning accuracy comparable to a total station. At the same time, operation is intuitive—follow the visual arrow on the screen—so even first-time users won’t be confused. Another important point is the portable, single-operator equipment. LRTK operates with a smartphone and a palm-sized receiver, eliminating heavy tripods and bulky instruments. Walking the site is not a burden and there’s no setup time, so many points across a wide area can be positioned and navigated quickly without breaks.

Moreover, the LRTK app innovatively uses camera AR display as an aid during navigation. In short, when you raise the smartphone near the target point, a "virtual pile (AR marker)" appears on the camera view, indicating the location as if a physical stake were present on the ground. If your position overlays the virtual stake on the screen, you can be confident you’re standing at the design point. This visual feedback increases confidence in pile-driving operations.

Comparison with Traditional Piling and Problem Solving

Coordinate navigation-based piling addresses many issues inherent in traditional methods. The following compares the old approach and outlines the benefits.

• Required personnel and skills: Traditionally, a skilled surveyor and an assistant were needed, and becoming proficient took time. With LRTK, one person can operate it without special certifications or years of experience. Even sites suffering from a shortage of skilled workers can complete pile positioning with fewer personnel.

• Work speed: Using a total station, time is consumed setting up and packing up equipment and aligning angles for each point. On large sites, repositioning the instrument often requires redoing measurements. Coordinate navigation allows immediate movement to the next target, greatly reducing time per measurement point. For example, ten piling points that once took half a day might be finished in just 1–2 hours with LRTK in some cases.

• Accuracy and reliability: Manual surveying involves human error, such as misreading measurements or misplacing marks. Coordinate navigation provides guidance based on digital data, so points are always shown according to design values. Real-time error readouts during work let you notice and correct deviations immediately, reducing variability in position accuracy and improving confidence in quality.

• Re-establishment and rework: Stakes and markers can get displaced or removed by heavy equipment. Traditionally, recovering a lost stake required calling the survey team. With coordinate navigation, anyone can quickly restore the point at any time. If the design coordinates are retained, even a disappeared point can be shown on site immediately, minimizing rework.

• Cost and adoption barriers: Robotic automatic-tracking total stations or high-precision GNSS units can enable single-person operation but are expensive and often out of reach for small and medium enterprises. They also require unique software operation and maintenance. LRTK, by contrast, leverages a smartphone and a small receiver, reducing upfront costs and offering an app-like user experience that’s easy to learn. Sites that previously gave up on 3D construction due to cost or technical barriers now have a practical solution.

In short, the coordinate navigation + LRTK combination fundamentally resolves inefficiencies of traditional methods. Carrying heavy survey equipment, worrying about weather, and struggling with staffing are all greatly reduced, enabling accurate piling with small teams and short timeframes. This is a major step forward for broader adoption of 3D construction.

Use Cases: Effects of Coordinate Navigation in the Field

Sites that adopted coordinate navigation report various positive impacts on efficiency and quality. Here are some concrete examples.

• Piling for large-scale solar farms: In mega-solar installations requiring hundreds of piles over vast areas, LRTK’s coordinate navigation proved powerful. Previously, survey teams set up batter boards (chōhari) from reference points and operators used hand signals to position machinery for pile installation. After introducing LRTK, site supervisors could direct pile locations one after another solo. On-screen markers and AR piles allow operators to guide machinery accurately to the designated positions. As a result, overall piling times were dramatically reduced—sometimes to less than half of the previous duration. Additionally, measured coordinates for each pile could be recorded on site, enabling immediate verification that locations were within a few centimeters of design values; any deviations could be corrected before mounting frames, preventing later issues.

• Reproducing survey points at disaster recovery sites: In landslide-affected areas, it’s essential to record and revisit exact measurement points. A local government used LRTK to save coordinates and orientations from an initial survey, then used the coordinate navigation function for a follow-up survey several months later. Different personnel were able to return to precisely the same locations and capture photographs at the same orientations and angles. This allowed accurate data comparisons over time, aided recovery assessments, and centralized field notes and photos in the cloud for improved workflow efficiency.

• Confirming boundary points on rural land: In mountainous development sites where boundary stakes are often obscured by trees and vegetation, LRTK helps confirm land boundary markers. By importing boundary coordinates from cadastral maps and navigating to them on site, workers can pinpoint boundary stakes even in dense undergrowth. Feedback from users included comments like "faster than searching with a metal detector" and "no more wasted time in large forests from wrong guesses." Even reference points hidden under vegetation or snow can be located by digging where coordinate navigation indicates, greatly improving the reliability of inspections.

These examples show that coordinate navigation-based piling and surveying deliver both productivity gains and quality assurance on site. Reduced work time leads to lower labor costs and shorter schedules, while improved accuracy cuts down rework and defects in later stages, contributing to overall cost savings and increased project reliability. Because all data are recorded digitally and shared, stakeholders can collaborate more smoothly: construction managers can check positioning results and photos on the cloud from the office and give real-time directions. Coordinate navigation + LRTK therefore improves not only the act of driving piles but also on-site communication and management.

Innovation through Combination with AR Display

Combining coordinate navigation with AR (augmented reality) display further enhances convenience and transforms the on-site experience. LRTK leverages high-precision positioning to overlay 3D models and markers on the smartphone camera view without spatial offset. This makes previously imagined "design completion images" and invisible reference points directly visible on site.

For example, the LRTK app can AR-project registered design drawings or model data on site. Displaying a completed building or structure model on the ground lets all site staff intuitively share the finished image and simplify construction decisions. In civil works, projecting design lines (such as road centerlines or final elevations) onto the ground enables verification by comparing the current terrain or earthwork status against the design. You can instantly see information like "the road edge will be here" or "fill should reach this height" at a glance.

For piling, the aforementioned AR pile marker is particularly useful. When viewing the target area through the smartphone, a virtual colorful stake appears to mark the exact location on the ground. Even in low-light or open-field conditions with no physical markers, the screen clearly indicates "drive the pile here!" eliminating missed markings. On steep or hazardous slopes where close approach is unsafe, you can view the AR display from a safe distance to confirm the position without approaching. With AR, workers no longer rely solely on instrument readings but can cross-check digital information with the actual scene. This fusion of intuition and data is a genuine innovation for construction sites.

Looking ahead, AR integration promises even broader possibilities. For example, if LRTK’s guidance could be experienced hands-free through AR smart glasses, direction arrows and models would appear in the worker’s field of vision while both hands remain free—highly convenient during active tasks. While the smartphone screen is already practical, AR glasses for pile-navigation may soon become feasible. As 3D construction × AR advances, the gap between drawings and the field will narrow further and the entire construction process will become more seamless.

Benefits for Small Teams and SMEs

LRTK’s coordinate navigation is not just for large firms—small teams and small-to-medium enterprises (SMEs) stand to gain significantly. Here are the main advantages for sites with limited personnel and budgets.

First, the low initial investment threshold is notable. Traditional ICT construction equipment is expensive and often requires training dedicated operators, making it hard for smaller companies to adopt. LRTK, composed of a smartphone, a small receiver, and a service subscription, can be put into operation as soon as the essentials are acquired. Prices are generally lower than conventional surveying equipment, so SMEs can cost-effectively adopt advanced technology.

Second, the simplicity and ease of use are invaluable for teams with limited staff. Even without a veteran surveyor, site supervisors or workers can perform surveying and pile positioning during downtime. Handling tasks in-house instead of outsourcing reduces costs and lead times. Feedback from sites that introduced LRTK includes remarks such as: "Time spent on surveying was drastically reduced, allowing staff to focus on other critical tasks," and "We no longer had to worry about the precision of pile positions, giving more leeway in construction planning." For small teams, improving each person’s productivity has an outsized impact on overall project performance, and LRTK can be a powerful ally.

Also noteworthy is that multiple functions are consolidated in one device. Besides coordinate navigation, LRTK offers single-point surveying (recording point positions), automatic coordinate stamping of photos, point-cloud acquisition via 3D scanning, as-built (construction outcome) data checks, and cloud-based team sharing. Achieving all of this with separate devices and software would require large investment and complex operations; LRTK lets you complete these tasks with just a smartphone. Even firms with limited capital can implement cutting-edge construction management comparable to larger companies. This contributes to uplift across the industry by making digital benefits widely accessible.

Future Outlook and Industry Impact

The piling revolution driven by coordinate navigation is just beginning, but it points to transformative changes across the construction industry. First, we can expect wider adoption of digital surveying and construction technologies. Government initiatives like the Ministry of Land, Infrastructure, Transport and Tourism's i-Construction support this trend, and easy-to-use, high-precision tools like LRTK will accelerate the industry's digital transformation (DX). In the future, with all site data digitally managed and shared—including construction histories—scenes like comparing paper piling drawings with the field may become a thing of the past.

Also expected is the establishment of new construction styles centered on LRTK. For example, integration with automated machine control. Although 3D machine guidance and machine control are already in use, LRTK could serve as a high-precision positioning hub enabling machines to autonomously move to specified locations and perform excavation or placement. Combining drone-based wide-area 3D survey data with real-time feedback from planning to as-built inspections could make smart construction commonplace, shortening schedules, improving quality, and reducing previously invisible waste and risks.

There are also human-resource implications. The industry may shift from reliance on craftsmen skilled in surveying and batter-board staking to a generation adept with tablets and smartphones. If construction becomes a tech-enabled, smart workplace attractive to younger workers, it could help address labor shortages and skill transfer. Technology that complements or replaces parts of veteran intuition and experience can enhance safety and reduce mistakes. In short, the piling revolution brought by coordinate navigation has the potential to effect continuous, industry-wide change rather than being an isolated improvement.

By envisioning this future, it’s clear that next-generation surveying and construction methods—unbound by traditional conventions—can dramatically boost on-site productivity and reliability, contributing to overall industry advancement. Technologies like LRTK will increasingly be seen as key to balancing "accuracy × efficiency."

Conclusion and a Natural Path to Simple Surveying with LRTK

This article has explained the revolutionary progress of piling work through coordinate navigation in the context of 3D construction and the features of LRTK that make it possible. Pile position setting, once dependent on manpower and experience, is now becoming a task that anyone can perform quickly and accurately thanks to LRTK. By achieving centimeter-level precision and intuitive AR guidance with a familiar tool—the smartphone—LRTK is a game changer for construction sites.

If you’re a construction manager who feels the traditional approach presents problems, there’s no need to worry, "Can we really use this?" LRTK’s simple equipment configuration and easy operability mean it can be deployed on site without special qualifications or intensive training. Start with small projects or limited applications to experience its convenience and benefits firsthand. The experience of achieving professional-level surveying with minimal steps using only a smartphone will likely change on-site conventions.

Combining accuracy and speed in construction is a source of competitive advantage for any project. If you feel any inefficiency or uncertainty in your surveying or piling processes, consider LRTK’s simple surveying features. Embracing the latest technology will enable anyone to implement 3D construction easily and bring about an era where site productivity and quality assurance go hand in hand.