High-precision positioning anyone can do with a layout guidance app: solving labor shortages

Table of Contents

• Measurement and layout work at construction sites and the challenge of labor shortages

• What is a layout guidance app?

• How high-precision positioning anyone can perform works

• Benefits of introducing a layout guidance app

• Single-person stake-driving work: on-site use case

• Simple surveying with LRTK

• FAQ

Measurement and layout work at construction sites and the challenge of labor shortages

In recent years, the construction and civil engineering industries have faced a serious labor shortage. In particular, survey and layout technicians are aging, and there is a shortage of younger personnel, so it is common to hear on-site complaints that “there aren’t enough people who can do surveying.” If reliance on experienced surveyors continues, there is an increased risk that work will be delayed when such specialists are absent, or that construction progress will be affected. Moreover, traditional methods that depend on experience and intuition take time to pass on skills to newcomers, and adapting to a shrinking workforce has become increasingly difficult.

Conventional layout (stake-driving) work typically uses dedicated instruments such as total stations and levels and is generally carried out by teams of two or more. Typically, one person operates the survey instrument while another stands at a distance holding a staff (rod) or prism to mark the position. This two-person workflow demands more personnel and time as the site scale increases, placing a significant burden on site managers. In addition, setting up and leveling the survey instrument on a tripod, and re-setting up whenever the instrument point is moved, require time-consuming preparation and cleanup, making the process inefficient. Furthermore, survey point information collected on site was often recorded in paper field books and later transcribed into drawings at the office. If measurements were missed or recording errors occurred on site, re-visiting the location to remeasure added rework, which was a major loss when a limited number of staff had to manage multiple sites.

Given these factors, continuing traditional layout methods amid labor shortages is becoming increasingly difficult. The industry as a whole is strongly demanding labor-saving and efficiency improvements through digital technology, and the Ministry of Land, Infrastructure, Transport and Tourism is promoting “i-Construction” and on-site DX (digital transformation) to support productivity improvements. One promising trend is the realization of “single-person surveying,” which leverages the latest technologies to allow surveying work to be completed by one person. If layout tasks that previously required two or more people can be performed accurately by a single worker, it could greatly help alleviate labor shortages while shortening construction schedules and improving quality.

What is a layout guidance app?

One solution that enables single-person surveying is the “layout guidance app.” A layout guidance app runs on a smartphone or tablet and uses GPS/GNSS to assist with on-site positioning tasks such as stake-driving. If coordinate data for control points and stake positions extracted from design drawings are preloaded into the app, it calculates in real time the difference between your current position and the target position on site and displays guidance on the screen.

The app screen shows maps or camera images and provides guidance such as “east by ○ cm (○ in); north by ○ cm (○ in).” By simply following the instructions and moving accordingly, you can reach the intended location, allowing even non-experts to pinpoint points accurately without hesitation. Some apps also provide voice guidance or use AR (augmented reality) to overlay virtual markers or arrows on the camera view, intuitively indicating “this is the design position.” Much like a car navigation system guiding you to your destination, a layout guidance app makes on-site positioning easy for anyone.

How high-precision positioning anyone can perform works

A layout guidance app enables intuitive positioning, but how is its accuracy ensured? Typically, the GPS built into smartphones or car navigation systems has errors on the order of several meters, which is insufficient for precise layout on construction sites. However, by using GNSS-capable surveying equipment or services alongside the layout guidance app, high-precision positioning with errors of only a few centimeters is achievable.

The key is a high-precision positioning technology called RTK (real-time kinematic). RTK corrects position in real time by comparing satellite positioning error information between a base station (reference point) and a rover (measuring terminal). In Japan, network RTK services using the Geospatial Information Authority’s continuous reference station network or private reference station services are widespread; by receiving correction data over the Internet from a smartphone, centimeter-level positioning can be achieved without installing a dedicated base station on site. Additionally, Japan’s quasi-zenith satellite “Michibiki” provides a centimeter-level augmentation service (CLAS), which allows devices to receive correction signals directly from satellites and maintain high accuracy even in mountainous areas where mobile communications are poor. In short, using a small GNSS receiver that can connect to a smartphone, you can know your current position outdoors with sufficient survey accuracy—within a few cm (within a few in).

Moreover, the layout guidance app itself incorporates features that make “accurate layout by anyone” possible. The app automates specialist equipment settings and complex calculations, so users only need to follow on-screen instructions, press buttons, or select points to complete tasks. Because design drawings and survey point information can be viewed on the smartphone’s high-resolution screen, there is no need to squint at paper drawings and measure distances with a tape. Visual display of the offset between the current location and the target point allows someone performing layout for the first time to work without confusion. Thus, through advances in both hardware and software, layout work is shifting from skilled artisan tasks to digital operations that anyone can handle.

Benefits of introducing a layout guidance app

So what concrete benefits can be obtained by introducing a layout guidance app on site? Below are the main advantages, compared with conventional methods.

• Labor saving and the ability to work alone: Using a smartphone and GNSS for layout, one person can complete all tasks without an assistant. Less experienced staff can be entrusted with on-site positioning, allowing work to continue despite labor shortages. Situations that used to require waiting for a specialist surveyor can be handled with in-house personnel, eliminating “survey waiting” times.

• Shorter work time and improved efficiency: With one person able to move freely, workflow for layout is greatly simplified, reducing time spent on site movement and equipment setup. For example, even when marking many points across a large site, a layout app allows you to walk from point to point and drastically shorten the time compared to conventional methods. Some sites that adopted smartphone surveying systems reported that stake-out work that used to take half a day was completed in about one hour, clearly demonstrating efficiency gains.

• Reduction of human error and quality improvement: Layout guidance apps can automatically record measured points and save them to the cloud. This prevents transcription errors or missed measurements on paper and ensures accurate positional records for reliable quality control. Because construction is based on high-precision coordinate data, rework and construction mistakes due to misalignment are also reduced. The ability to maintain consistent accuracy regardless of the operator helps standardize work quality instead of relying on veteran intuition.

• Cost reduction: By leveraging smartphones, there is no need to purchase dedicated survey instruments or control terminals, significantly lowering initial costs. High-precision GNSS receivers have become smaller and less expensive in recent years, making them far more affordable than traditional large survey instruments. Some systems are offered as monthly services, allowing flexible operation by using the system only for the required period without owning equipment. When factoring in labor reduction and shorter work times, the total cost advantage becomes substantial.

• Intuitive and easy operation: The refined UI of smartphone apps means they can be operated intuitively without specialized knowledge. By simply tapping the screen, users can perform positioning and recording, so even beginners can learn the operation in a short time. Running on familiar smartphones reduces psychological barriers, allowing anyone to operate from day one. Map and drawing data can be zoomed in and out on the smartphone screen, enabling accurate reading of detailed instructions on site.

• All-in-one versatility: The combination of a layout guidance app and a GNSS receiver can be used for a wide range of tasks beyond stake-driving. It can handle arbitrary point coordinate measurement, as-built (finished) measurements, and even 3D scanning using the smartphone’s built-in LiDAR or camera—making it a single solution for surveying, as-built management, and inspection. Tasks that previously required separate instruments and software can be integrated within one app, serving as an “all-purpose surveying tool.” Collected data can be shared to the cloud on the spot, enabling real-time coordination with the office, which is another major advantage.

Single-person stake-driving work: on-site use case

Let’s see how on-site work actually changes when using a layout guidance app, using stake-driving (layout) as an example.

Consider setting out foundation centerline points at a construction site. Traditionally, a surveyor would perform back-sighting with a total station while another person measured around the site and drove stakes at the points. With a layout guidance app, before construction you create a list of control point coordinates and planned centerline coordinates from design drawings and import that data into the smartphone app.

On site, the GNSS receiver attached to the smartphone determines the current position while the app displays the target stake position. The smartphone screen then shows in real time the offsets such as “east by 5 cm (2.0 in), north by 10 cm (3.9 in).” The worker follows that guidance, moves gradually, and drives the stake where the offset reaches zero. Some apps even overlay virtual flags or markers on the camera image to indicate “drive the stake here,” so even first-time users won’t get lost. Previously, an assistant would shout “a little to the right!” and “there!” to fine-tune the position, but with the guidance app a single person can achieve the precise location.

When stake-driving can be done alone, layout efficiency improves dramatically. There is no need to coordinate staffing, and workers can start stake-driving immediately when needed. Also, coordinates obtained via GNSS are automatically linked to the reference coordinate system and recorded, so consistency can be verified later. The spread of layout guidance apps marks the arrival of an era when stake-driving is easy and highly accurate.

Simple surveying with LRTK

As described above, the combination of a layout guidance app and GNSS technology has a major impact on alleviating labor shortages and improving productivity. Still, some may wonder what equipment to adopt. As a final note, we introduce “LRTK” as an easy solution to start high-precision surveying.

LRTK is our surveying system that integrates an ultra-compact RTK-GNSS receiver, a smartphone app, and cloud services. By simply attaching a dedicated device for smartphones (LRTK Phone), an ordinary smartphone instantly becomes a centimeter-accuracy positioning terminal. LRTK supports network RTK and Michibiki’s CLAS, enabling high-precision positioning anywhere in Japan from urban to mountainous areas. Because it can receive correction information directly from satellites even when out of mobile coverage, stable accuracy is maintained regardless of communication environment. The device is palm-sized with a built-in battery, and is easy to carry with a smartphone in one hand.

The dedicated app is also highly user-friendly, allowing recording of the current position or taking photos with a single button, so beginners can use it without hesitation. In addition to navigation to stake positions, LRTK supports diverse on-site needs such as point-cloud surveying in conjunction with a smartphone’s LiDAR and as-built inspection using AR display of 3D design models. Collected survey data are uploaded to the cloud in real time, allowing the office PC to instantly check results and share them with stakeholders.

LRTK has already been adopted by local governments and construction companies, with feedback such as “waiting times for surveying disappeared and project schedules have more leeway” and “young staff could handle surveying even without veterans.” LRTK, which enables high-precision “single-person surveying” for anyone, is a powerful ally for sites struggling with labor shortages. If you are interested in high-precision positioning with a layout guidance app, we encourage you to experience simple surveying with LRTK.

FAQ

Q: Do I need a special qualification or advanced knowledge to use a layout guidance app? A: No, special qualifications are not required. As long as you can perform basic smartphone operations, a layout guidance app is designed for anyone to use. Advanced settings and calculations are handled automatically by the app, so users only need to follow on-screen instructions to achieve high-precision positioning and layout. After a brief introductory training during implementation, even those with limited surveying experience can start using it on site immediately.

Q: What positioning accuracy can I obtain? A: Accuracy depends on the GNSS receiver and correction service used, but generally horizontal accuracy of about 2–3 cm (0.8–1.2 in) can be obtained. With RTK surveying, if high-quality equipment and good satellite reception are ensured, centimeter-level positioning sufficient for construction surveying is possible. This level of precision is far superior to typical smartphone GPS errors of several meters and is reliable for layout and as-built management.

Q: Do I need to provide my own survey base station? A: Basically, you do not need to provide your own base station. Systems that support network RTK can use correction data distributed over the Internet from a reference station network, and in Japan you can also receive corrections via Michibiki’s CLAS signal. Therefore, centimeter-level positioning on site is available without a dedicated base station or expensive fixed installations.

Q: Can it be used in mountainous areas where mobile coverage is unavailable? A: Yes. Even where smartphone signals do not reach, high-precision positioning is possible if CLAS augmentation signals from Michibiki can be received. CLAS-capable receivers like LRTK can maintain stable accuracy in mountainous areas or remote islands where reference station networks do not reach. However, if satellite signals are physically blocked (e.g., inside tunnels or inside buildings), positioning becomes difficult, so the intended use is primarily outdoors.

Q: Are introduction and running costs high? A: The cost of introducing a layout guidance app is much lower than purchasing traditional survey equipment. Even high-performance GNSS receivers are more affordable than conventional survey instruments, and they can be used in combination with commercial smartphones or tablets, eliminating the need to buy extra terminals. Some services offer subscription plans without device purchase, enabling flexible operation tailored to small sites or project durations. Considering labor cost savings, initial investment is often recouped quickly.

Q: What other uses are there beyond layout? A: Layout guidance apps and smartphone GNSS can be applied to a wide range of surveying and measurement tasks beyond stake-driving. For example, for as-built surveying you can use 3D scan functions to acquire point-cloud data of terrain or structures and perform quality inspection or create as-built drawings by comparing them with design models. For earthwork quantity calculations, volumes of fill and cut can be automatically computed from the acquired point cloud. AR features can overlay 3D design models onto the site view to compare current construction status with planned design. These tasks, which used to require specialized survey instruments and advanced software, become accessible to anyone with a layout guidance app.

Q: Is it easy for small companies or sites to introduce? A: Yes. In fact, small and medium-sized sites with limited staff stand to benefit the most from layout guidance apps. With low initial costs and the ability for in-house staff to complete surveying without specialized skills, companies can avoid outsourcing and rely on their own teams. Because learning the operation is straightforward, companies that previously relied entirely on veterans for surveying can shift to younger staff conducting measurement tasks. Even when a small team manages multiple sites, layout guidance apps enable efficient positioning work at each site. Small sites facing labor shortages tend to experience the greatest benefits from adoption.

Q: Can it be used in rainy or dusty conditions? A: Many smartphone GNSS receivers and related devices are designed to be rugged for construction site use. Some products have dustproof and waterproof (IP-rated) designs and can be used in light rain. Smartphones themselves can be operated in the rain if they are waterproof models or used with dedicated waterproof cases. However, because these are electronic devices, it is wise to avoid prolonged use in heavy rain or situations where devices may be submerged. With appropriate measures, layout guidance apps can be used reliably even in dusty, harsh sites or in extreme heat or cold.