Can Measuring and Layout Be Done Solo? The New Normal on Construction Sites Opened Up by LRTK

Table of Contents

• Background for why solo surveying and layout is being required

• Traditional surveying and layout work and inefficient points

• Emergence of new technologies that make solo layout possible

• Benefits of solo layout enabled by smartphone RTK "LRTK"

• Toward a future where solo layout is the norm

• FAQ

Background for why solo surveying and layout is being required

"What if surveying and layout work could be done by just one person..." — such a seemingly fantastical scene on construction sites is taking on a sense of reality. Until now, surveying and layout work has been commonplace to perform with at least two people. For example, one person operates the surveying instrument while another holds a staff (rod) or prism and stands at the survey point; such two-person teams have long been the norm. However, in recent years a style that completes surveying and layout with just one person has been attracting attention. Behind this trend are the construction industry’s overall labor shortages and increasing needs for efficiency.

Japan’s civil engineering and construction industry is loudly calling out a serious shortage of personnel. As aging leads to experienced surveyors reaching retirement one after another and the number of young entrants declines, securing personnel who can perform surveying and layout is a major challenge. At the same time, demands for work-style reform and productivity improvements have increased the need to operate sites with fewer people. In such circumstances, tasks that can be done by one person become key to site operations. Naturally, surveying and layout work is no exception, and methods that allow one person to perform layout have been in demand. If one-person layout becomes possible, flexibility in personnel allocation greatly improves and manpower can be redirected to other important tasks. As a team, downtime while waiting for surveying is reduced, and having the ability to measure immediately when needed directly smooths project progress. In other words, realizing solo layout is not merely labor-saving; it can be the key to raising overall site productivity and flexibility.

Traditional surveying and layout work and inefficient points

Layout is the work of accurately transferring positions and elevations from the design drawings to the actual site. It includes marking foundation locations of buildings, marking pile centers for bridges, and drawing building reference lines (layout lines); this process plays a crucial role that affects construction quality. Because high precision is required, traditional layout has been carried out by specialized surveying teams with the utmost care. However, that approach has several inefficiencies.

First, it requires multiple people. Typically a total station (TS) optical surveying instrument is used, with a surveyor operating the TS while another worker carries a prism and moves. For marking pile positions, the TS operator measures angles and distances and gives instructions while an assistant marks the instructed points with piles or markings. Because such work cannot be done without at least two people, arranging personnel can be cumbersome. Especially on large sites where layout is done in many places, workers must call out to each other at each point, and the work tends to take time.

Second, equipment setup takes time. When using a total station, preparations start with mounting the tripod, leveling, and aligning the instrument to known control points. If the number of layout locations increases, the tripod must be repositioned each time and backsight procedures redone, taking up significant time. Also, the range measurable by a TS has line-of-sight (visibility) constraints. If there are obstacles (material piles, heavy machinery, etc.) between the point to be measured and the TS, measurement may be impossible, requiring moving the instrument or devising measurement procedures, which adds extra work.

Third, data recording tends to be analog. Traditionally, results measured on site were marked on the ground or piles, and coordinate values and other data remained only in the instrument or on handwritten notes. Later transferring these to drawings or other devices requires manual input, causing human error and time loss. As described above, while total-station layout can achieve high precision, it has issues in terms of flexibility and efficiency, leading to the image that "layout work = troublesome work."

Emergence of new technologies that make solo layout possible

Recent technological innovations are changing these conventions in layout work. New approaches have appeared in the world of surveying and layout, which previously relied on manpower and conventional equipment. One of these is the automatically tracking total station. The latest TS models automatically track prisms like a robot to measure distances and angles, allowing an operator to perform layout alone while walking with a prism. However, automatic-tracking TS units are expensive and require time to learn, so they are not something everyone can immediately introduce.

Other methods that have become common include photogrammetry using drones and 3D point-cloud surveying with terrestrial laser scanners, which can acquire terrain data without humans measuring directly. These are revolutionary ways to reduce the labor of surveying itself, but they are mainly used for terrain measurement and as-built management and are not well suited to layout tasks such as pile-driving or marking layout lines. Drones also have constraints like weather and no-fly zones, meaning they cannot always be freely used on site.

Particularly noteworthy among these is solo layout enabled by GNSS positioning technology using satellites. RTK surveying, a type of surveying that uses GNSS (Global Navigation Satellite System), has become a powerful method to enable solo layout. RTK (Real Time Kinematic) is a technology that combines positioning signals from satellites with correction information distributed from a base station in real time to pinpoint positions with centimeter-level accuracy (a few inches). Using RTK, one can measure high-precision coordinates while moving around the site without mounting heavy optical equipment. A major advantage is that even distant points on a large site can be measured without concerns about line-of-sight; simply carrying the receiver and walking to the point is enough.

With these latest technologies, the fixed notion that "surveying and layout require large equipment and multi-person teams" is beginning to collapse. A symbol of this shift is the emergence of pocket-sized RTK-GNSS receivers. The era when anyone can perform precise positioning anywhere using a palm-sized device is approaching. And the product that embodies this concept is exactly "LRTK". Next, let’s see how LRTK, a simplified RTK system using a smartphone, makes solo layout possible and is rewriting site conventions.

Benefits of solo layout enabled by smartphone RTK "LRTK"

LRTK is an easy-to-handle RTK-GNSS positioning system developed by a startup originating from Tokyo Institute of Technology. By attaching a business-card-sized small receiver to a smartphone and operating it with a dedicated app, it is designed so that even those without specialized knowledge can perform centimeter-level positioning (half-inch accuracy). Tasks that were once thought to be the work of trained surveyors can be handled intuitively with LRTK. It is quietly sparking a revolution on sites as a tool that lets you "measure anytime, anywhere."

So what specific benefits does solo layout using LRTK offer? Here are the main points.

• High-precision positioning: The RTK method enables high-precision positioning with errors on the order of several centimeters. This accuracy is a far cry from conventional standalone GPS and is sufficient for pile positioning and marking reference lines.

• Mobility and portability: The slim, lightweight device fits in a pocket (weighing approximately 125 g), so walking around a large site is not a burden. There is no need to carry tripods or heavy equipment up and down slopes; one person can easily perform layout even in confined or uneven locations.

• Ease of operation: The smartphone app has a simple UI and is intuitive to use. Just tap a button at the point you want to measure to record coordinates — complex settings and calculations are automated. Even without special skills, users can start using it immediately.

• All-in-one functionality: A single unit covers everything from point surveying to area surveying and even pile-position guidance functions. It includes diverse features such as photogrammetry, AR-based site simulation, and distance/area/volume calculations from measurement data, allowing it to meet a wide range of on-site measurement needs with one device.

• Cloud integration: Measured data can be uploaded to the cloud from the smartphone with a single tap. This eliminates the need to return to the office and manually transcribe into drawings, enabling real-time information sharing with remote offices. Because layout results can be shared immediately, all stakeholders can proceed with construction while understanding the current situation.

• Low cost for one-per-person use: Priced very reasonably compared to dedicated surveying instruments, LRTK breaks the constraint of "expensive, so only one unit per site," making an era in which each worker carries an LRTK increasingly realistic. If everyone from newcomers to veterans can measure with their own device, waiting times and work being person-dependent can be reduced.

With these advantages, LRTK is a tool that dramatically lowers the barrier to layout work. For example, tasks that traditionally required two to three people and half a day, such as marking pile centers, are beginning to be completed by one person in a few hours using LRTK. Some sites adopt a hybrid operation in which critical points are double-checked with TS or levels as before, while large numbers of points are handled quickly by smartphone RTK. This approach is far more efficient than doing everything by traditional methods while still ensuring the required accuracy.

Concerns that "the latest surveying equipment is difficult to handle" are unnecessary. Because LRTK is operated via a smartphone app, people accustomed to smartphones can master it quickly. The app clearly displays the current positioning status (satellite reception and RTK accuracy), and warns if accuracy is insufficient. Users can complete layout by following on-screen instructions without needing to understand complex technical terms. By enabling anyone on site to operate like a surveyor, LRTK holds tremendous potential.

In actual civil engineering sites, solo layout by LRTK contributes to productivity and safety improvements. For example, on earthwork (land formation and excavation) sites, supervisors or heavy equipment operators can take an LRTK device from their pocket and measure heights and distances at required points right there. This greatly reduces the need to call a surveyor or to stop machinery while waiting. Moreover, in steep slope situations where surveyors previously had to carry heavy tripods, LRTK can be carried with one hand, allowing safer work. The need for multiple people to enter hazardous slopes is reduced, resulting in lower workload and improved safety.

Toward a future where solo layout is the norm

In this way, the smartphone RTK system LRTK is set to significantly change the conventions of layout work. When solo layout becomes possible, it will not only alleviate personnel shortages but also change how sites are run. Even with limited personnel, multiple tasks can more easily proceed in parallel, contributing to shorter schedules, cost reductions, and stricter quality control. An environment where you can measure whenever you want could become the trump card for improving productivity on future construction sites.

The spread of solo layout also promotes the site’s digital transformation (DX), not merely reducing manpower. Tools like LRTK enable work that used to rely on craftsmen’s intuition and experience to be driven by data. If layout data is shared in real time via the cloud and linked with ICT construction machines and other construction management systems, the boundary between site and office disappears and smoother decision-making becomes possible. This aligns with the Ministry of Land, Infrastructure, Transport and Tourism’s "i-Construction" initiative and supports industry-wide digitization and labor-saving efforts.

A future in which solo layout is the norm is right around the corner. As a concrete solution, LRTK is a very attractive option. The revolutionary ease of being able to start solo layout work today with just a smartphone and a small device—without difficult preparation or special qualifications—is compelling. Try LRTK and you may be surprised to find that tasks you used to leave to the surveying team can now be done by you alone. Why not take a step to introduce this new normal in layout, improving productivity while ensuring quality? For detailed product information and case studies, please check the LRTK official website.

FAQ

Q: What are the benefits of doing layout solo? A: The biggest benefit is saving personnel and time. Tasks that previously required two to three people can be done by one person, enabling quick response even on sites short of workers. It also creates flexibility to perform layout in parallel with other tasks, reducing wasted time when machinery or workers are stalled waiting for surveying. Digital recording and sharing of data reduce human error and improve quality control. Overall, it simultaneously achieves productivity gains and cost reductions.

Q: What is RTK surveying? How is it different from traditional surveying? A: RTK surveying is a technology that dramatically improves satellite positioning accuracy. Ordinary GPS surveying can have errors of several meters, but RTK uses correction information from a base station to compute corrections in real time, improving accuracy to a few centimeters (a few inches). This makes precise positioning and elevation measurements required on construction sites possible using satellite positioning alone. Unlike optical surveying instruments (such as total stations), RTK does not require time-consuming instrument setup or line-of-sight assurance; once the antenna is set up, you can measure a wide area mobilely.

Q: What is LRTK? A: LRTK is a small RTK-GNSS receiver used in combination with a smartphone. It is a positioning terminal system developed so that anyone can easily perform high-precision positioning via a dedicated smartphone app. It is palm-sized and far more user-friendly than traditional surveying instruments because the app automates complex operations. Often called a "simplified RTK system," it is a versatile layout tool that non-surveyors can use on site.

Q: Can beginners with no surveying experience master LRTK? A: Yes, LRTK is designed to be easy for beginners. Operations are performed in the smartphone app, and by following on-screen prompts you can measure and record with button taps. Coordinate transformations and height calculations are automated, so even without specialized knowledge you can obtain accurate layout results. Satellite reception state and accuracy are displayed in real time, so even those unfamiliar with the equipment can use it with confidence. With a short training or on-site practice, anyone should be able to put it to practical use quickly.

Q: Is the accuracy really sufficient when one person performs layout? A: If used properly, accuracy can be sufficiently ensured. Positioning accuracy obtained with LRTK using the RTK method is typically about 2–3 cm (0.8–1.2 in), which is acceptable for general building and civil engineering layout. LRTK is actually used for foundation pile center marking and positioning of structures and meets the required accuracy. However, for final stages requiring millimeter-level precision, it is sometimes prudent to double-check with traditional optical instruments (total stations or levels). Also, due to the nature of GNSS positioning, it cannot be used indoors or in tunnels where satellites cannot be received; in such cases, combining with conventional methods covers those situations. In short, by using LRTK in the right places, solo layout can balance accuracy and efficiency.

Q: What do I need to introduce LRTK? A: Basically, you can start with an LRTK unit and a smartphone. LRTK is available in types that connect to a smartphone’s Lightning or USB-C port, and you attach it to your compatible smartphone. An internet connection is required to receive satellite correction data, but within Japan free correction services using "Michibiki" (quasi-zenith satellites) and public control points are available. Initial setup is guided by the app and is not difficult. No special qualifications are required to introduce it, and once you learn how to use it, you can use it on site from tomorrow. Depending on site needs, preparing a tripod or pole (monopod) allows operations in various styles such as fixed positioning or handheld positioning.