Solo RTK Stakeout: The Latest Surveying Method That Eliminates the Need for a Total Station

Table of Contents

• Background: Why solo stakeout is in demand

• What is RTK stakeout?

• Why a total station becomes unnecessary

• Advantages of RTK stakeout

• Cautions and limitations of RTK stakeout

• Technologies that enable solo RTK surveying

• Simple surveying with LRTK

• FAQ

Background: Why solo stakeout is in demand

On construction sites, staking out (setting stake positions) must be performed accurately and efficiently. Stakeout is a critical process that marks the reference positions for buildings and structures on the ground, and positional errors can lead to construction mistakes and rework, so careful surveying and marking are indispensable. Traditionally, stakeout required skilled surveyors and specialized equipment, and working in pairs was the norm.

However, in recent years, with severe labor shortages and an aging workforce in the construction industry, reducing manpower and improving efficiency have become urgent. Against the background of initiatives such as *i-Construction* promoted by the Ministry of Land, Infrastructure, Transport and Tourism and the spread of digital technologies like drone surveying and machine guidance, the soloization of surveying tasks has also become a major challenge. New surveying methods have emerged to meet the growing demand for “completing stakeout alone” and “keeping surveying running with limited personnel.”

In conventional stakeout, surveying crews used tape measures and total stations (TS) to transfer coordinates from drawings to the ground and install markers called chauhaki (batter boards) or stakes. This could be difficult depending on weather and terrain, and the work took time and effort. Having people mark stake positions in areas where heavy machinery operates also carries safety risks, and hazardous footing increases danger. To solve these issues and enable anyone to quickly and safely mark stake positions, the cutting-edge positioning technology called RTK has attracted attention.

What is RTK stakeout?

RTK stakeout is a method of performing stakeout using real-time kinematic (RTK) high-precision GNSS positioning. Position information obtained by RTK-GNSS is far more precise than conventional standalone GPS positioning, with errors on the order of a few centimeters (a few inches). This meets the accuracy required for typical civil engineering and land development sites and is sufficiently applicable to stakeout tasks such as building layout and roadway centerline staking. In RTK positioning, a base station (reference point) and a rover (the surveyor’s unit) simultaneously receive satellite signals and correct errors in real time by differencing their data. Therefore, across wide sites the operator can simply walk around holding the antenna, verify their position against specified coordinates, and place stakes at target points.

Using RTK for stakeout removes the need for the line of sight that was previously required. Traditionally, optical aiming with a total station meant that obstacles on the straight line between measurement points made work difficult. But with RTK-GNSS, as long as the sky is open and satellite signals can be received, coordinates for arbitrary points can be obtained directly even across obstacles. For example, boundary stake installation on expansive development sites or locating structures within sites with poor visibility can be done efficiently because you can measure your current position via satellites if you are anywhere near a reference point. RTK survey data can also be recorded digitally, eliminating the need for handwritten notes and allowing direct use in drawings and 3D models.

Why a total station becomes unnecessary

There are several reasons RTK stakeout is said to make a “total station unnecessary.” First, RTK allows tasks that formerly required two people with a total station (TS) to be completed by one person. TS surveying required one person to set up and observe with the instrument while another held a prism at moving points. There are robotic TS units with automatic tracking that make solo surveying possible, but they are expensive and require skilled operation, so adoption is limited. In contrast, RTK positioning systems using a small GNSS receiver paired with a smartphone are designed to be intuitive even for users without special skills, and they greatly lower the barrier to surveying.

Second, the speed and convenience are major factors. When using a TS, you must set the instrument on a tripod and perform setup each time, but with RTK you can start surveying as soon as you pick up the antenna and walk. Because large equipment and precise setup are unnecessary, preparation time is reduced and you can begin confirming stake positions whenever needed. The equipment is compact and lightweight, offering excellent portability, and movement within the site is easy. You don’t have to lug heavy tripods and batteries, making it simple for one person to survey at heights or in confined spaces.

Third, there are cost advantages. Total stations and high-precision optical surveying instruments are generally very expensive, with large costs for acquisition and maintenance. On the other hand, smartphone-linked RTK-GNSS receivers that have become widespread are more affordable, lowering the equipment cost barrier. Small and medium-sized construction firms and local government bodies that lacked dedicated surveying teams can now adopt high-precision surveying at lower cost.

For these reasons, using RTK technology has made stakeout without relying on a total station a realistic option. However, as discussed below, RTK is not万能; it is important to use traditional instruments where appropriate. Choosing the right technology for the task allows both efficiency and accuracy to be achieved.

Advantages of RTK stakeout

Here are the benefits that solo RTK stakeout brings to the field. The labor-saving and acceleration enabled by the latest technology directly improve site productivity.

• Labor savings and reduced personnel: Because surveying tasks can be completed by one person, large numbers of personnel are no longer required for stakeout and as-built measurements. Even sites struggling with staffing shortages can accomplish necessary surveying with minimal members.

• Time savings and improved efficiency: Large-scale equipment setup and multi-person coordination are unnecessary, so surveying can start immediately when needed. Work time is reduced and overall workflow efficiency improves. Positioning data are automatically recorded and shared digitally, enabling faster post-processing and reporting.

• High-precision positioning: RTK-GNSS can achieve centimeter-level precision. Even easy-to-use equipment can obtain high-precision data, ensuring quality for stakeout and as-built management.

• Portability and responsiveness: Many devices fit in a pocket, making site movement and transport easy. One person can go to high places, confined areas, or distant points with ease, allowing flexible response to any site condition.

• Improved safety: Minimizing surveying personnel reduces the number of people entering hazardous areas where heavy machinery operates. Shorter task durations also lower safety risks for marking on busy roads and other high-traffic environments.

• Low-cost adoption: Compared to traditional optical surveying instruments, small RTK-GNSS receivers and software are inexpensive. Small businesses that could not afford expensive TS units can now adopt high-precision surveying at accessible prices.

• Ease of data utilization: Survey results are obtained as digital data from the start and can be imported directly into CAD drawings or 3D models. The need to re-enter values from paper is eliminated, and cloud sharing enables immediate distribution to stakeholders, making data-driven workflows from surveying to design and construction management smooth.

Cautions and limitations of RTK stakeout

There are points to be aware of and limits to the convenience of RTK stakeout. First, GNSS positioning is heavily affected by the satellite reception environment. In narrow urban sites surrounded by tall buildings, in dense forests, or under bridges, satellite signals can be blocked and positioning tends to become unstable. In some cases, errors may temporarily reach several tens of centimeters (several dozen inches), or the solution may not stabilize and remain in a “float” state. In such environments, it is advisable not to force RTK stakeout but to use traditional total station surveying or batter boards for verification.

Also pay attention to the required level of accuracy. For common civil engineering uses, RTK’s approximately 2–3 cm (0.8–1.2 in) accuracy generally suffices, but for critical stakeout tasks requiring millimeter-level precision—such as steel-frame column locations or bridge foundation pile centers—relying solely on RTK is risky. In such cases, it is safer to use RTK to obtain the approximate position and then perform detailed measurement and adjustment with a total station or optical level; a two-stage approach secures accuracy. At critical points, double-checking is essential: use RTK to save labor but finish with traditional methods where necessary.

Furthermore, to use RTK stably you need to learn equipment handling and positioning techniques. Modern RTK devices and apps are user-friendly and easy to operate, but basic precautions remain—keep the antenna vertical, set the antenna height correctly, and constantly monitor signal conditions. When first using RTK, don’t jump into live stakeout work; practice in open areas to confirm the stability of positioning results. Gradually gaining experience will let you confidently apply RTK stakeout on-site.

Technologies that enable solo RTK surveying

What has made RTK stakeout a practical method for anyone are the many supporting technologies advanced in recent years. In particular, the emergence of compact surveying equipment and smartphone apps has been a major turning point. Previously, centimeter-accuracy GNSS surveying equipment weighed several kilograms and was stationary, handled only by trained surveyors. Now, palm-sized high-performance GNSS receivers can be attached to smartphones or tablets and used via Bluetooth in compact RTK systems. The smartphone handles the user interface and communication, while the small receiver performs high-sensitivity positioning, making RTK surveying accessible to anyone.

In Japan, the environment for obtaining correction information for RTK positioning is also becoming well established. Network RTK using the Geospatial Information Authority of Japan’s permanent GNSS station network (VRS methods, etc.) is widely available, and if a GNSS receiver can communicate, centimeter-level positioning is possible without setting up your own base station. Also, the Quasi-Zenith Satellite System (QZSS) “Michibiki” has started a centimeter-level positioning augmentation service (CLAS), enabling RTK-like positioning by receiving correction information directly from satellites even in remote mountainous or island areas without mobile coverage. With these infrastructure developments, solo RTK surveying—once a high hurdle—has become much more accessible.

Moreover, AR (augmented reality) technology strongly supports solo stakeout. By overlaying design stake positions and guidance arrows on a smartphone or tablet camera view, the screen alone intuitively shows “where to place the stake.” It’s like a “navigation system for stakeout,” guiding even inexperienced workers to the specified position without hesitation. For example, simply walking the site with a tablet can display distance information like “X cm remaining” as you approach the target, and when you reach the designated spot the on-screen marker appears to line up exactly with the stake position on the ground. Combining RTK’s high precision with AR visualization is bringing an era in which anyone can perform stakeout easily and accurately.

Simple surveying with LRTK

To make the most of RTK technology, easy-to-use devices and systems are important. Previously, conducting RTK surveying on-site required expensive dedicated gear and complicated setup, but now solutions like LRTK allow anyone to easily introduce RTK surveying. LRTK is an all-in-one surveying system that combines a compact, high-performance GNSS antenna attachable to a smartphone or tablet, a dedicated app, and cloud services. Your smartphone becomes a high-precision GNSS receiver, and intuitive app controls enable straightforward surveying.

For example, with LRTK even personnel with limited surveying experience can perform everything from simple as-built measurements to precise stakeout. Tasks that used to require two people can now be reliably guided to stake positions by one person using LRTK’s AR navigation. The LRTK series has significantly lowered the adoption barrier for RTK-only surveying for small and medium construction companies and local governments. As a modern RTK solution compatible with i-Construction, it is attracting attention as a tool that can dramatically improve on-site productivity and surveying accuracy.

If you worry, “I want to use RTK to do stakeout alone, but I don’t know what to prepare,” LRTK provides the necessary devices, app, and cloud environment in a package, making introduction smooth. Pricing and operation are designed with usability in mind, so companies without dedicated surveying departments can handle it. As RTK becomes more widespread, surveying work is expected to shift from being a “craftsman skill” to a “task anyone can do” through digital technology. As a forerunner, simple surveying with LRTK has the potential to change long-standing site practices.

FAQ

Q: How accurate is RTK surveying? Is RTK alone really enough? A: RTK-GNSS positioning can achieve horizontal accuracy of about 2–3 cm (0.8–1.2 in) and vertical accuracy of about 3–5 cm (1.2–2.0 in) in good open conditions. This level of accuracy is sufficient for many civil engineering surveys and construction management tasks. However, in urban canyons or forested areas, temporary errors on the order of several tens of centimeters (several dozen inches) have been reported. For important reference points or pile centers, it is advisable to double-check RTK measurements with a total station or similar instrument.

Q: If I have RTK, are total stations and levels no longer necessary? A: RTK is very convenient, but it does not completely replace total stations (TS) or optical levels. Each instrument has strengths. RTK allows one person to measure many points over a wide area, but for millimeter-level precision or tasks requiring optical straight-line extensions, TS or levels are more stable. The ideal approach is to use RTK and traditional instruments appropriately according to site conditions: leverage RTK where it brings efficiency, and use TS or levels for final adjustments to exploit the strengths of both.

Q: What is needed to use network RTK? A: To use network RTK (such as VRS), you need an RTK-capable GNSS receiver and a means to receive correction data over the Internet. Specifically, you need a device capable of mobile data communication (a receiver with a built-in SIM or tethered smartphone) and a subscription to a service that provides GNSS correction information. In Japan, both paid correction services by private providers and free services leveraging the Geospatial Information Authority’s permanent station data are available. Receiving such correction data lets you perform centimeter-level positioning in real time without setting up your own base station. Note that network RTK cannot be used where there is no mobile coverage; in such cases, you must either set up a local base station and transmit corrections by radio or switch to post-processing (PPK).

Q: I’m nervous about introducing RTK for the first time. Can I learn to use it? A: Modern RTK equipment and software are designed with the user in mind, and basic operations are not difficult. Systems like LRTK guide you through the process in a smartphone app, making them accessible even without extensive expertise. Still, understanding correct equipment setup and satellite reception tips helps achieve maximum accuracy. Start by practicing in open areas, then gradually try more complex sites as you gain experience. Manufacturer support can help resolve questions. With proper learning and practice, even beginners can become proficient with RTK stakeout in a short time.

Q: What is simple surveying with LRTK? A: LRTK is a solution that combines an ultra-compact RTK-GNSS receiver usable with smart devices, a dedicated app, and cloud services. It enables centimeter-level surveying (simple surveying) without complex setup or specialized equipment. For example, attaching an LRTK receiver to a smartphone and walking the site automatically captures high-precision position data and manages and shares it in the cloud. Tasks that used to be performed by veteran surveyors—such as stakeout and as-built measurements—can be accurately carried out by less experienced personnel using LRTK’s intuitive AR navigation. In short, simple surveying with LRTK is a new surveying method that achieves RTK-level precision with more user-friendly equipment and operation, and its effectiveness is already being demonstrated on many sites.