Table of Contents

• The gap and challenges between the field and the office

• What is surveying DX?

• Field and office connected via the cloud

• What is the smartphone RTK "LRTK Phone"?

• Features and benefits of LRTK Phone

• Use cases that directly connect the field and the office

• Simple surveying enabled by LRTK

• Conclusion

• FAQ

The gap and challenges between the field and the office

Here we consider the challenges in information sharing and task coordination between the field and the office. In conventional surveying work, it was common to bring back data collected on site and process and review it in the office. Values and drawings measured by surveyors in the field were delivered to the office relying on USB drives or paper records, after which drawings and analyses were performed. This process created time lags, and there was a gap that made it difficult to immediately convey changes or problems that occurred on site to the office.

Furthermore, with a shortage of experienced survey technicians and an aging workforce, it has become difficult to split tasks among multiple people at a single site. When the person responsible for surveying at the site and the person responsible for CAD drawing or data analysis in the office are different, there is also a risk of coordination errors and delays in information transfer between them. Even if a request such as “we want this spot measured additionally” comes up later, if personnel and equipment have already been withdrawn, someone must go back to the site. In this way, there has been a physical and temporal separation between the field and the office, leading to decreased efficiency and productivity. How to eliminate this information disconnect between the field and the office is the key to improving productivity at future construction sites.

What is surveying DX?

A key solution attracting attention to solve these issues is “surveying DX (digital transformation).” Surveying DX refers to efforts to fundamentally reform surveying processes by fully utilizing digital technologies. Under initiatives such as the Ministry of Land, Infrastructure, Transport and Tourism’s *i-Construction*, digitization aimed at improving productivity and reducing labor at construction sites is accelerating. Specifically, this includes the miniaturization and performance improvement of surveying instruments, the introduction of ICT surveying (such as drone photogrammetry and 3D laser scanner point-cloud surveying), data sharing via cloud services, and automation to improve work efficiency.

However, advanced technologies such as drone photogrammetry and terrestrial laser scanners require expensive equipment and specialized skills, so they are not something everyone can immediately adopt. This has led to a new approach that enables precise positioning by combining a smartphone with a small device.

What surveying DX aims for is to create an environment where “anyone, even one person, can easily perform surveying.” Precision surveying that used to require a specialized technical team can be made more accessible through digital technology. In addition, by creating a system in which the field, the office, and all stakeholders such as clients and subcontractors share digital data and can grasp and make decisions in real time, it is expected to reduce wasted work and lead to faster decision-making.

Field and office connected via the cloud

Cloud services are indispensable to realizing surveying DX. By centrally managing and sharing data on the cloud, surveying data obtained on site can be sent to the office immediately and made available for viewing and use by all stakeholders. For example, if point-cloud data of terrain or measurement results of as-built conditions measured on site are uploaded to the cloud on the spot, design staff or project managers in the office can instantly check that data. This significantly changes the conventional flow of “measure on site, bring it back, then check it.”

The advantages of cloud integration go beyond mere speed of data transfer. Constant sharing of the latest information reduces communication losses between the field and the office and prevents rework caused by mismatched understanding. In addition, because data is securely accumulated via the internet, risks such as loss of paper ledgers or USB drives are reduced. Remote experienced technicians can also view field data in real time and give advice, enabling cloud services to play a strong role in skill transfer and training. By literally “directly connecting” the field and the office, collaboration that transcends geographical distance and time differences becomes possible.

What is the smartphone RTK "LRTK Phone"?

A powerful tool that has emerged to practice surveying DX and cloud integration on site is the LRTK Phone. LRTK Phone is a compact RTK-GNSS device that attaches to a smartphone and transforms a standard smartphone into a high-precision surveying instrument. RTK (real-time kinematic) is a positioning method that corrects satellite positioning (such as GPS) errors to achieve centimeter-level accuracy, and it usually required expensive dedicated equipment. LRTK Phone is a product developed by Lefixea, a startup originating from the Tokyo Institute of Technology. Despite being pocket-sized, weighing approximately 165 g and having a thickness of approximately 1 cm (0.4 in), it enables RTK positioning through a built-in high-performance antenna and multi-band GNSS receiver.

This device can be attached to a smartphone (iPhone/Android) with a dedicated phone case or bracket with one touch, and operates by connecting to the phone via Bluetooth or USB. It contains a battery and antenna and can perform continuous positioning outdoors for about 6 hours. By installing a dedicated app on the smartphone, control of positioning, data recording, and uploading to the cloud can all be done in one place. Unlike conventional surveying equipment, it requires almost no complicated preparation or specialized knowledge and is characterized by intuitive operation that anyone can handle. LRTK Phone can also be mounted on a dedicated monopod (pole); in that case, like traditional GNSS surveying instruments, the pole tip can be placed on a ground survey point to acquire the position. Since the app can perform pole-length offset correction, point surveying with centimeter-level accuracy (half-inch accuracy), including vertical accuracy, can be easily carried out.

It can truly be called the next-generation surveying tool with the ease of “if you have a smartphone, you can measure right away.”

Features and benefits of LRTK Phone

Let’s organize the concrete features and benefits of LRTK Phone that bring DX to the field.

• High-precision positioning: LRTK Phone uses RTK-GNSS technology to obtain position coordinates within an error range of a few centimeters (a few inches). While a smartphone alone can have GPS errors of several meters, using LRTK Phone makes it sufficiently capable of tasks that require precision, such as layout of structures or boundary measurements.

• Portability and ease of use: It is a compact device that fits in a pocket and does not require heavy equipment like traditional stationary surveying instruments. It is easy to carry to the site, and preparation is complete simply by attaching it to the smartphone with one touch. Its simple design allows even beginners to use it without hesitation, so measurement can begin as soon as you arrive at the site.

• Cloud integration features: Measured data can be uploaded to the cloud from the smartphone on the spot and shared immediately with the office and other team members. Not only coordinate data but also photos, notes, and voice comments can be linked and saved, allowing you to record and report the site situation as it is. This enables the office to make quick decisions and instructions while looking at the latest information coming from the field.

• A variety of measurement functions: LRTK Phone provides a variety of functions in cooperation with the smartphone’s camera and sensors, not limited to position measurement. For example, combined with a LiDAR-equipped smartphone, you can 3D-scan the surrounding terrain and structures to create point-cloud data, and that point cloud will be assigned accurate coordinates via RTK. Using AR (augmented reality) functions, you can also visualize design drawings or the locations of underground buried objects on site. Automatic calculation of measured earth volumes and as-built management by overlaying with existing drawings are examples of tasks that used to be processed back in the office but can now be done in real time on site.

• Positioning continues even outside communication coverage: Typical RTK-GNSS devices are difficult to use where there is no network connection, but LRTK Phone supports the centimeter-level augmentation service (CLAS) provided by Japan’s Quasi-Zenith Satellite System “Michibiki.” This allows high-precision positioning to continue using augmentation signals from satellites even at mountain sites or locations outside communication coverage. Combined with internet-based reference station services (VRS), ensuring stable positioning accuracy in both urban and mountainous areas is a reassuring feature for field work.

• Low-cost introduction: Conventional surveying instruments and 3D scanners were expensive and had high barriers to introduction, but LRTK Phone offers subscription plans that include the necessary hardware and software, greatly reducing initial costs. It is realistic to operate by fitting one device to each worker’s smartphone and carrying it at all times, enabling simple surveying tasks that were previously outsourced to specialized contractors to be completed in-house, leading to cost reduction.

Use cases that directly connect the field and the office

Now let’s look at concrete scenes showing how the field and the office are directly connected by using LRTK Phone.

Real-time sharing for immediate feedback: Suppose the ground elevation is measured to check progress at a construction site. Traditionally, that data might have been taken back and drawn up and shared with stakeholders several days later. However, elevation data measured with LRTK Phone is synchronized to the cloud immediately, allowing design staff and supervisors in the office to check it in real time. If feedback requests “Please measure a few more points” are made, instructions can be sent to the field workers on the spot, and additional data can be re-shared within minutes. With two-way connectivity between the field and the office, you gain the speed to complete a PDCA cycle within the same day.

Remote expert support: For surveys on special terrain or when troubles occur, advice from experienced technicians may be required. By sharing photos and point-cloud data obtained with LRTK Phone via the cloud, veteran technicians in the office or at remote locations can view the data and provide advice remotely. For example, you can receive instructions such as “There’s something odd about these measurements—please remeasure here,” allowing course correction on the spot. As a result, waste such as returning later to re-survey due to data deficiencies is reduced, improving quality.

Navigation for pile-driving and installation work: Using LRTK Phone’s positioning guidance functions, field workers can identify installation coordinates decided in the office without confusion. For example, in stake-out work such as pile-driving or bolt installation, surveyors used to mark layout points with batter boards or chalk lines. With LRTK Phone, navigation and AR displays that guide workers to pre-set coordinates let them follow the smartphone screen to the exact point. This directly links the planned positions set in the office with on-site work, enabling accurate construction without positional deviation even by a single operator.

Immediate utilization of 3D scan data: 3D point-cloud data acquired by a smartphone camera or LiDAR can also be used immediately via cloud sharing. For example, if you scan the shape of an excavation site with LRTK Phone to create an as-built point-cloud model and upload that data to the cloud, the office’s construction management personnel can quickly calculate earth volumes or compare it with the design model. Because data measured on site can be reflected in construction management the same day, it directly contributes to shortened schedules and faster decision-making. Point-cloud data records the real appearance of the site in detail that photos or drawings cannot show, making it effective for shared understanding among stakeholders.

Site records with geotagged photos: During on-site surveys at the design stage or infrastructure inspections, there are occasions when you want to record site photos together with the photographic location. Using LRTK Phone’s “positioned photo” function, photos taken with the smartphone can be automatically linked with accurate latitude, longitude, and orientation and saved. When photos uploaded to the cloud are checked by the office, location-specific information that is hard to understand from photos alone can be accurately grasped. This makes post-analysis and report creation by comparing photos with drawings smoother and significantly improves the sharing and recording accuracy of site conditions.

Simple surveying enabled by LRTK

As described above, by using LRTK Phone the walls between the field and the office are removed, and the speed and efficiency of surveying work improve dramatically. In particular, the benefits of the simple surveying that LRTK brings are “speed,” “ease,” and “accuracy.” Being able to measure immediately when needed, share immediately, and move to the next action immediately—the cycle enabled by LRTK becomes a powerful tool that directly improves on-site productivity. Because it can be handled without advanced specialist skills, site staff can perform surveys themselves even amid labor shortages and provide high-quality data immediately.

By introducing such a simple surveying system, small-scale surveying and as-built checks that used to be outsourced to external specialists can be completed in-house, leading to cost reduction and accumulation of know-how. If you feel that surveying tasks at your site are time-consuming or labor-intensive, consider introducing LRTK Phone, a next-generation surveying DX tool. It will surely become a reliable partner that greatly expands the possibilities of surveying and dramatically improves coordination between the field and the office.

Conclusion

DX in surveying is not just about high-tech adoption but a means to remove the barriers between the field and the office to improve productivity and quality. The combination of smartphone surveying devices represented by LRTK Phone and cloud integration is attracting attention as a concrete solution. From an era of relying on heavy equipment and complicated procedures, we have now reached a point where high-precision surveying and data sharing are possible with a single smartphone, and workflows are undergoing dramatic change.

By directly connecting the field and the office in real time, delays and errors in information transmission are reduced, and all stakeholders can always grasp the latest situation. As a result, decision-making accelerates, wasted work is reduced, and safety is improved. To avoid falling behind in the wave of surveying DX, it is wise to take a familiar first step by adopting tools like LRTK Phone. That does not merely mean introducing new surveying equipment, but obtaining the future in which the field and the office are seamlessly connected.

FAQ

Q: How accurate is the positioning with LRTK Phone? A: Using RTK corrections, positioning is possible to within a few centimeters (a few inches) in planar position, and under good conditions errors can be less than 1 centimeter (less than 0.4 in). Since normal smartphone GPS has errors of about 5–10 m (16.4–32.8 ft), using LRTK Phone dramatically improves accuracy.

Q: What do I need to use it? A: Basically, you need a smartphone, the LRTK Phone device, and the dedicated app to start positioning. Correction information required for positioning (internet-based RTK reference-station data or augmentation signals from satellites) is included in the service, so there is no need to prepare an expensive additional base station.

Q: In what situations can it be used? A: It can be used in a wide range of situations such as as-built management at construction sites and comparison with design data, photogrammetry during infrastructure inspections, damage recording at disaster sites, and land boundary confirmation. From small-scale measurements to detailed analysis using 3D point clouds, LRTK Phone can handle many tasks, making it especially useful when you want to do “a bit of surveying” on your own.

Q: Do I need specialized knowledge or qualifications to operate it? A: LRTK Phone is designed so that positioning and data sharing can be performed with intuitive app operation. Basic knowledge of GPS and maps is sufficient to use it, and you do not need a special surveyor qualification to operate it. However, if you intend to use results as official public surveying outcomes, verification by a qualified professional may be required separately.

Q: How long does the battery last and what about durability? A: The device’s internal battery enables about 6 hours of continuous positioning. If used while powered from a mobile battery via USB Type-C, it can handle longer work periods. Durability is designed for use at construction sites and it operates without problems even with some rain or dust. However, pay separate attention to the waterproof and dustproof performance of the smartphone itself.