CONEXPO-CON/AGG Notable Trends: Construction DX Advancing through Single-Operator Surveying and Construction Equipment Guidance

Table of Contents

• Introduction

• Labor shortages in overseas civil engineering markets and the trend toward construction DX

• Innovation in one-person surveying (single-person surveying)

• Advances in construction machine guidance (machine guidance)

• Comparison with conventional methods

• On-site DX using cloud services and AR integration

• Implementation benefits: Advantages by stakeholder

• Utilization of simplified surveying using LRTK

• FAQ

Introduction

At the 2023 CONEXPO-CON/AGG, one of the world’s largest construction equipment exhibitions held in Las Vegas, USA, many cutting-edge technologies symbolizing the construction industry’s digital transformation (DX) were showcased. Among them, particular attention was focused on "one-person surveying" (one-man surveying) and "machine guidance" (machine guidance). In overseas construction markets where labor shortages are becoming severe, these technologies, which enable efficient on-site work with small crews, have come into the spotlight as <strong>key technologies for construction DX</strong>.

Attempts to complete surveying work single-handedly and to support heavy equipment operators with advanced technologies directly contribute to improved productivity and safety on site. This article explains, with reference to the latest trends in the overseas civil engineering industry, the innovations that one-person surveying and machine guidance bring to construction sites. It also touches on use cases for GNSS positioning and RTK technologies that underpin these systems, and the potential for on-site DX through integration with cloud and AR. Finally, we introduce the advantages and applications of the useful <strong>simple surveying solution "LRTK"</strong> for putting this DX into practice, to help you consider its introduction to your sites.

Labor Shortage in Overseas Civil Engineering Markets and the Trend toward Construction DX

In recent years, overseas civil engineering and construction markets have been facing a serious labor shortage. Due to an aging workforce and a decline in young entrants, it is becoming increasingly difficult to secure the survey technicians and skilled operators required on site. At the same time, infrastructure demand remains strong, increasing the need to complete many projects with limited personnel. To address this challenge, the adoption of digital technologies aimed at automating work and reducing manpower, in other words "construction DX," is accelerating.

At construction sites overseas, including in the United States, initiatives that use ICT (civil engineering IT) and IoT to improve productivity are becoming mainstream. For example, machine guidance (automatic control and guidance of heavy equipment) based on 3D design data, and cases where on-site workers themselves use GNSS equipment to perform surveying and as-built verification are becoming common. At CONEXPO-CON/AGG as well, many companies proposed these technologies as solutions to labor shortages.

What is notable in countries abroad where technology adoption is advancing is the idea of "doing more work with fewer people". Specifically, by <strong>dramatically increasing each individual's work efficiency</strong>, the trend is to offset workforce reductions and maintain or improve productivity. The key to this is technologies such as one-person surveying and construction equipment guidance, which are featured here. In the next chapter, we will first take a closer look at one-person surveying, an innovative change in the field of surveying.

Innovation in One-Man Surveying (Single-Person Surveying)

One-man surveying is an umbrella term for methods and technologies that enable surveying work, which traditionally required two or more people, to be completed by just one person. Until now, surveying typically involved one person operating surveying instruments such as a total station while another person held a staff (survey rod) at a distant point. However, in recent years, new approaches have emerged that overturn this convention, allowing a single operator to carry out surveys alone.

In addition to the aforementioned labor shortage, there is a growing need to streamline surveying. With veteran surveyors aging and a shortage of younger personnel, voices in the field are increasingly saying, "It would be ideal if surveying could be done by a single person." In Japan, the Ministry of Land, Infrastructure, Transport and Tourism-led *i-Construction* advocates using ICT to improve construction efficiency, and, alongside drone surveying and machine guidance, it is expected to encourage the adoption of one-person surveying.

So, what skills are necessary to carry out surveying alone? With recent technological advances, the very methods of surveying are undergoing significant change. Conventional optical surveying, which used to be mainstream, inevitably required multiple personnel. However, today the following solutions have been put into practical use.

• Robotic total station: A total station equipped with an automatic tracking function; when an operator carries a prism and moves, the instrument automatically follows the target. This makes it possible for one person to perform angle and distance measurements.

• UAV (drone) surveying: Acquire terrain data by aerial photogrammetry and create 3D models and drawings in post-processing. It has the advantage of surveying wide areas in a short time.

• Laser scanner surveying: Use a ground-based 3D laser scanner to capture surrounding point cloud data at once, enabling highly detailed measurements.

These are all groundbreaking technologies that reduce manpower and improve efficiency, but in practice they also present challenges in terms of operating costs and conditions. Robotic total stations are expensive and require advanced operational skills, and drones and laser scanners also face weather limitations, flight restrictions, and high barriers in specialist knowledge. Therefore, what is attracting particular attention is one-person surveying using GNSS (satellite positioning)-based RTK surveying.

RTK (Real-Time Kinematic) is a technique that uses correction information from a base station to improve GNSS positioning accuracy to the centimeter level, and by using a dedicated receiver (rover), a single person can obtain high-precision position coordinates in real time. Unlike conventional methods that require setting up a total station or securing line of sight, it offers high mobility, allowing one person to move around a large site and rapidly collect survey points. In other words, even on vast development sites or road construction sites, <strong>a single worker can complete surveying simply by walking with a GNSS receiver</strong>.

The advantages of one-person surveying are immeasurable. Because it eliminates the need to allocate multiple people, it enables cost savings from reduced manpower, removes the waste of waiting for someone to be available, and being able to survey immediately when needed speeds up the entire site. For example, in situations where heavy-equipment operators traditionally had to wait for the survey team to arrive, if workers can perform the survey themselves they can reduce waiting time and resume work immediately. If survey data can be shared digitally right away, rework can be avoided and the risk of schedule delays is also reduced.

Thus, the technology that has seen the most field implementation to enable single-person surveying is RTK-GNSS surveying. In recent years, new tools have also emerged that make this RTK technology even easier to use. That will be covered in a later chapter, but next let’s take a look at another trend: construction machinery guidance (machine guidance).

Advances in Construction Equipment Guidance (Machine Guidance)

Construction equipment machine guidance (also called machine control) is a system that equips heavy machinery with GPS/GNSS and sensors to guide and assist operators based on 3D design data. It detects the machine position and blade height of bulldozers, excavators, and other machines in real time, displays deviations from the design surface on an in-cab monitor, and can automatically control the blade. This enables operators to perform highly accurate earthmoving and grading work without relying on experience or intuition.

The main reasons machine guidance is attracting attention are also labor shortages and the need to improve work efficiency. With the number of experienced operators declining, it is urgent to establish an environment where <strong>even newcomers can work with accuracy close to that of experienced workers</strong>. By introducing machine guidance, accurate construction can be achieved by relying on the machine even without veterans, which in turn leads to more consistent quality and less rework. Also, traditionally surveyors drove stakes and set up batter boards at the site, and operators used those as references for excavation and embankment, but after introducing machine guidance the physical installation of stakes can be greatly reduced. In other words, because it allows work to continue while reducing surveying effort, it also contributes to shorter overall schedules and cost savings.

At CONEXPO-CON/AGG, many manufacturers were exhibiting the latest machine-guidance-compatible equipment. In the latest models, the operator interface has become more intuitive and has been improved so operators can grasp the necessary information at a glance (such as height differences to the design surface and slopes). There are also features such as automatic adjustment of a hydraulic excavator’s bucket angle and systems that visualize compaction levels using sensors mounted on rollers, indicating applying digital guidance to all processes.

Notably, machine guidance, which until now has been used mainly on large-scale sites, is spreading to <strong>small- and medium-sized projects and compact construction equipment</strong>. In fact, at CONEXPO-CON/AGG 2023, inexpensive retrofit guidance kits for small-scale site development and sewer construction were announced, showing the technology’s widening reach. As a result, it is becoming easier for not only major general contractors but also small and medium-sized contractors to adopt these systems, and the industry as a whole is expected to be lifted.

The effectiveness of machine guidance has already been demonstrated on-site. In one overseas road improvement project, there are reports that after introducing guidance, working time was reduced by about half. Compared with the days when operations relied on human experience and rules of thumb, re-surveying and over-excavation were reduced, leading to savings in fuel and materials. Furthermore, by reducing stake-driving tasks, workers had fewer occasions to enter areas around heavy equipment, producing the additional benefit of improved safety. Indeed, machine guidance is becoming the standard on future construction sites.

Comparison with Conventional Methods

Let’s clarify how new technologies such as one-man surveying and machine guidance specifically differ from conventional construction methods. The table below shows a comparison with conventional approaches for surveying work and heavy equipment operation.

Table 1. Surveying Operations: Conventional Method vs. One-man Survey (RTK Survey)

Table 2. Heavy Equipment Operations: Conventional Method vs. Use of Machine Guidance

As the above comparison makes clear, both one-man surveying and machine guidance achieve substantial labor savings and quality improvements by covering traditional inefficient procedures and human-dependent elements with digital technology.

On-site DX through Cloud Utilization and AR Integration

As a means to further unlock the true value of single-operator surveying and machine guidance, there is integration with cloud technologies and AR (augmented reality). By sharing and managing data in the cloud, information transfer between the field and the office — and even between construction machinery — becomes smoother, and construction management is becoming real-time.

For example, if you upload position coordinates and as-built data obtained from surveying to the cloud, they can be shared instantly with office engineers and other teams. This eliminates the traditional time lag of "waiting for survey results before updating drawings" and speeds up on-site decision making. Also, when design changes occur, they can be reflected immediately in construction equipment guidance systems and surveying terminals via the cloud, enabling construction consistently unified with the latest data. There is no need to run around the site with USB drives, and it's also possible to update by simultaneously distributing updates to multiple machines remotely.

Meanwhile, the use of AR (Augmented Reality) is also opening up new possibilities for on-site DX. For example, initiatives are under way to use tablets and AR glasses to display the site while overlaying the finished form from the design drawings and the locations of buried objects onto the real space. For heavy equipment operators, systems are being researched that project design lines and target heights onto the windshield. If this becomes practical, <strong>workers will literally be able to determine the correct position and height just by looking</strong>, dramatically improving the intuitiveness and accuracy of work.

DX solutions linked with the cloud and AR are enabling the entire series of processes—surveying → design → construction → inspection—to be digitally and seamlessly connected. This is revolutionary not merely because it reduces manpower, but because it makes possible advanced construction management based on data. For example, advanced cases overseas have emerged in which progress during construction is scanned by drones or robots and converted into point cloud data, which is instantly analyzed on a cloud-based digital twin (virtual site) and reflected in the next day's construction plan. In Japan as well, it is expected that on-site DX combining these cloud and AR technologies will become increasingly widespread.

Implementation Benefits: Advantages for Each Stakeholder

The technological innovations described so far bring benefits to people in every role involved in construction projects. Let's organize the specific advantages from each perspective.

ゼネコン・施工会社: They can improve productivity while supplementing labor shortages, directly leading to shorter project delivery times and cost reductions. Reduced rework due to improved accuracy cuts wasteful expenditures and is expected to raise overall profit margins. Introducing the latest technologies also contributes to enhancing corporate image and competitiveness in winning contracts. Especially for overseas projects, DX is becoming standardized, so responding to these technologies will be an appealing point for acquiring new orders.

重機オペレーター: Machine guidance provides visual assistance for operation, reducing workload. Having consistently accurate guidance eases psychological pressure, which in turn contributes to safer operation. Learning speeds increase, making it easier for newcomers to become effective quickly. For veterans, reliance on intuition and experience is reduced, lessening physical and mental burdens and allowing them to concentrate on more advanced tasks and on mentoring.

施工管理者（現場監督）: Because site data can be acquired and shared in real time, progress management and quality control become significantly easier. Time spent waiting for surveying setup or dealing with rework is reduced, enabling focus on overall, bird’s-eye management. Information sharing with headquarters and design staff via the cloud becomes smoother, speeding up decision-making and helping to close the gap between site and office.

測量技術者: At first glance, one-man surveying might raise concerns that surveyors will no longer be needed, but in reality personnel with surveying expertise remain important. New technologies mean the role of surveying technicians will change. They will be freed from simple measurement-point tasks and be able to focus on higher value-added work such as planning-oriented control point setting, verification of as-built conditions, and data analysis. In addition, traditionally physically demanding tasks (such as long hours of surveying under intense sun) will be reduced, contributing to a safer environment that enables long-term active work.

In this way, the introduction of construction DX technologies brings positive effects to all stakeholders on-site. By reducing labor while improving quality, a virtuous cycle of "work becomes easier while outcomes improve" is created, and, in turn, it contributes to enhancing the sustainability of the construction industry as a whole.

Using LRTK for Simple Surveying

Finally, as one solution that allows easy implementation of the one-person surveying described above, we introduce "LRTK". LRTK is a palm-sized, high-precision GNSS receiver that can be used in conjunction with a smartphone, and is designed so that anyone can easily perform RTK surveying without complicated equipment operation or specialized knowledge.

Traditionally, positioning with centimeter-level accuracy (half-inch accuracy) required expensive surveying equipment and skilled technicians. However, by utilizing LRTK, simply attaching a small receiver to a smartphone with a dedicated app installed enables a single person to perform control point surveying and as-built verification. The positioning accuracy, both horizontal and vertical, is within ± a few centimeters (± a few inches) and is comparable to full-scale GNSS equipment, ensuring sufficient accuracy required on site. Because the collected data can be synchronized to the cloud in real time, producing drawings in the office immediately and sharing them with stakeholders is also smooth.

The advantages of LRTK are its portability and ease of use. Because equipment weighing only a few hundred grams can be brought to the site and high-precision surveying can be performed in a short time, it can quickly meet needs such as “I just want to measure this spot.” For example, even if additional surveying becomes necessary during a small-scale repair, with LRTK a single person in charge can respond immediately, keeping interruptions to the work to a minimum. Furthermore, since on-site staff can complete the task without calling a specialized surveying team, there is a significant cost benefit.

For companies and sites looking to advance construction DX, a simple surveying tool like LRTK is ideal as the first step in adoption. Its relatively low cost and the convenience of using existing smartphones let you try it on-site immediately and quickly see the benefits. The successful experiences gained from that will lead to the introduction of further DX technologies (machine guidance and cloud integration, etc.). Please take this opportunity to experience the advantages of single-person surveying with LRTK on-site and discover new possibilities in construction.

FAQ

Q: What is one-man surveying? A: One-man surveying (single-person surveying) is a method that enables surveying tasks that traditionally required two or more people to be completed by a single person. It utilizes robotic total stations and GNSS (RTK) positioning technologies, allowing surveying to be carried out without an assistant. It has attracted attention as a solution to labor shortages, and practical implementation is already progressing, mainly overseas.

Q: If machine guidance is introduced, do operator skills become unnecessary? A: Machine guidance is a technology that supports and complements operator control, but it does not make the experience and judgment of skilled operators entirely unnecessary. Rather, because guidance ensures the accuracy of basic tasks, operators can concentrate more on higher-difficulty work and on site safety checks. Beginners can perform work to a certain level, but the greatest effect is achieved when combined with the knowledge of experienced operators.

Q: Do these technologies require a large investment to implement? A: Implementation costs vary depending on the technology and equipment, but in recent years the range of price points has widened and there are increasingly affordable options even for small-scale projects. For example, retrofit-type machine guidance kits and smartphone-compatible surveying devices (LRTK, etc.) are significantly lower cost compared with traditional dedicated equipment. Also, because these technologies can deliver large cost savings through productivity improvements, there are many reports of initial investments being recovered in a short period.

Q: Is the accuracy of one-person surveying with GNSS sufficient? A: With RTK-GNSS surveying, you can expect accuracy of about ±1-2 cm (±0.4-0.8 in) in horizontal position and about ±3 cm (±1.2 in) in the vertical direction. This level of accuracy is acceptable for most civil construction surveying applications. However, satellite positioning is affected by reception conditions under trees and around high-rise buildings, so it is necessary to make on-site judgments such as alternating use with a robot TS depending on the situation. On earthwork sites and infrastructure projects with largely open work spaces, RTK-GNSS can provide sufficiently high-accuracy single-person surveying.

Q: Specifically, how should we proceed with introducing this on-site? A: First, we recommend trialing it on a small-scale site or for a portion of the workflow. For example, have the construction crew perform as-built checks with LRTK that were previously requested of the survey team, or try fitting an add-on guidance system to a single backhoe. By having on-site staff actually use it, the benefits and issues will become clear. Even a limited initial introduction can be expanded more easily to other trades and the entire site if it produces successful experiences. Also, make use of support from equipment manufacturers and service providers during implementation; receiving pre-training and operational support will help it become established on site. Even if there is resistance to new technology, once the benefits are felt you should be able to gain on-site understanding and cooperation.