Table of Contents

• What is tilt-compensated GNSS

• Why tilt compensation is needed (field challenges)

• How the technology behind tilt compensation works

• Features of LRTK equipped with tilt-compensated GNSS

• Case studies and use cases of field efficiency using LRTK

• Data sharing and measurement flexibility through cloud integration

• Compatibility and potential of tilt-compensated GNSS with cloud integration

• The overall picture of simple, high-accuracy positioning with LRTK

• Conclusion: Reasons to adopt LRTK for surveying

• FAQ

What is tilt-compensated GNSS

Tilt-compensated GNSS is a technology that uses sensors built into surveying GNSS receivers to detect the device’s tilt and enables accurate positioning even when the pole (survey rod) is tilted. Normally, GNSS positioning requires the receiver (antenna) to be placed vertically directly above the survey point. Tilt-compensated GNSS relaxes this vertical requirement and automatically corrects the coordinates of the ground target even when the receiver is tilted. For example, if the pole tip remains on the point to be measured but the pole becomes tilted, the device measures the tilt angle and orientation via internal sensors and corrects the position to where it would be if the device were ideally vertical.

Traditionally, surveyors adjusted the pole’s bubble level (spirit level) and repeatedly repositioned it to keep the receiver directly overhead. With tilt-compensated GNSS, even if the pole cannot be kept perfectly vertical, measurement errors are automatically corrected. As a result, surveying work is significantly sped up and positioning becomes easier even in narrow areas or on poor footing. Especially in recent years, advances in high-precision tilt detection using IMUs (inertial measurement units) have produced GNSS devices that can maintain centimeter-level accuracy even with large tilts of around 30°–60°. Tilt-compensated GNSS can thus be regarded as a new generation of GNSS technology developed to balance high-precision positioning and improved work efficiency.

Why tilt compensation is needed (field challenges)

The demand for tilt-compensated GNSS stems from various challenges encountered on survey sites. In conventional surveying, GNSS receivers or prisms must always be set vertically, which caused the following problems.

• Sites with limited space or many obstacles: In locations such as next to buildings or under trees, it was difficult to stand the pole vertically, making accurate positioning challenging. When there was no space to set the pole upright or when it was impossible to install it from directly above on a slope, conventional practice required abandoning the measurement or measuring from an alternate position.

• Increased workload and time: Adjusting the bubble in the level for each point to keep the pole vertical was time-consuming and a heavy burden on operators. Especially when measuring many points, posture corrections had to be made each time, increasing the total surveying time.

• Manpower and communication: In traditional optical surveying (transit or total station), it was common for a surveyor and an assistant to work in pairs. One person holds the pole while the other reads and gives instructions, requiring tight coordination. There was also risk of positional errors or mistakes due to miscommunication.

• Marking effort: In construction surveying, it was necessary to mark (chalk out) positions on the ground based on the design drawings before construction. This multi-step process—surveying → marking → construction—was inefficient, and markings could be misplaced or erased. A method that could more directly set out and position points was desired.

Given these challenges, the field required technology that made surveying “easier,” “solo-capable,” and “reliable.” In fact, reports indicate that latest GNSS surveying can reduce work time to about 1/6 compared to conventional methods. Tilt-compensated GNSS attracted attention as a key technology capable of solving these issues. If strict verticality of the pole is no longer a concern, one person can work efficiently and reliably, improving overall surveying productivity.

How the technology behind tilt compensation works

So how does tilt-compensated GNSS detect tilt and perform corrections? The core is sensor fusion technology using an IMU (inertial measurement unit). An IMU combines accelerometers and gyroscopes to rapidly measure three-dimensional motion (acceleration) and rotation (angular velocity) of the device. By integrating this IMU into the GNSS receiver and combining its outputs with GNSS-derived position information, tilt compensation is achieved.

The basic mechanism is as follows.

• Measurement of tilt angles and heading: The IMU inside the surveying device measures the receiver’s tilt angles (pitch and roll) and orientation (yaw) in real time. For example, it captures how many degrees the pole is tilted and in which direction in milliseconds.

• Calculation of the tip position: Given the GNSS antenna position (in its tilted state), the device calculates the coordinates of the pole tip contacting the ground from the tilt angles detected by the IMU and the pole length. In other words, it uses trigonometry to determine how many centimeters the tip is offset from the receiver position in the downward-slanted direction.

• Sensor fusion correction: GNSS positioning data and IMU tilt data are integrated to perform real-time correction to the point directly beneath the antenna. Crucial here is sensor fusion using advanced algorithms such as a Kalman filter. By fusing GNSS’s absolute position with the IMU’s relative tilt detection, position estimation can be stabilized at a higher accuracy than either source alone.

• Use of magnetic sensors (in some cases): Some models include a magnetic compass (geomagnetic sensor) in the IMU to obtain an absolute heading reference. However, magnetic sensors are subject to errors from metal and environmental influences, so many recent high-precision GNSS receivers estimate heading from gyros and accelerometers (self-calibration), simplifying magnetic calibration. Many modern devices achieve calibration that is close to “imperceptible”—requiring just a small movement at initial startup for automatic calibration.

Through the above processes, the receiver can always compute the accurate ground measurement point even when tilted. Importantly, IMU-based tilt correction is highly effective over short periods and produces results comparable to GNSS-alone accuracy. Sensor drift is routinely reset or corrected by GNSS signals, so within typical surveying durations there is no need to worry about significant accuracy degradation. Understanding this mechanism clarifies why tilt-compensated GNSS is reliable.

Features of LRTK equipped with tilt-compensated GNSS

LRTK is a cloud-integrated latest GNSS solution and, naturally, a positioning device equipped with tilt-compensated GNSS functionality. The LRTK device is an ultra-compact RTK-GNSS receiver designed to be attached to a smartphone; despite weighing just 125 g and being 13 mm thick, it includes a built-in battery. It is designed for one-touch attachment/detachment to a dedicated smartphone case, turning your phone into a high-precision positioning device whenever needed.

Main features of LRTK:

• Easy positioning with tilt compensation: Supports IMU-based tilt compensation, allowing you to attach the LRTK device to a pole tip and obtain the coordinates directly beneath the tip even if the pole is somewhat tilted. Even in narrow spaces where it is difficult to stand the pole vertically, LRTK can measure while maintaining accuracy. For example, you can accurately record coordinates next to building edges or at road manhole locations by simply tilting the pole and touching the tip to the target point.

• Centimeter-class high-precision RTK: LRTK supports RTK positioning and can obtain absolute coordinates with errors of only a few centimeters on site. In practice, horizontal accuracy of about ±1–2 cm and vertical accuracy of about ±3 cm are obtainable, and using the averaging function can improve precision to a few millimeters per point. This level of accuracy matches first-class GNSS equipment and is suitable for full-scale surveying tasks.

• Smartphone-integrated convenience: No heavy tripods or controllers are required. Because the device attaches to a smartphone and can be carried in one hand, you can keep it in your pocket and quickly take it out for positioning whenever needed. With an optional monopod (dedicated pole), you can perform more stable single-point measurements and piling tasks. When using a pole, the height offset can be corrected in the app with a single button, allowing you to obtain the tip’s coordinates without complicated calculations.

• Intuitive app operation: By installing the dedicated LRTK app on your smartphone, you can clearly display current coordinates and target points on the screen. Positioning starts with a single button, and acquired data is automatically organized and saved. In addition to latitude/longitude, the app automatically computes and displays Japan’s plane rectangular coordinate system and geoid heights (JGD2011 standard), and you can store date/time and notes for each point. Coordinate transformations, which previously required expertise, are handled in the background by the app, making it easy for anyone to use without mistakes.

• Multi-frequency and offline support: The LRTK receiver supports multi-GNSS and multi-frequency signals and is compatible with the centimeter-class augmentation service (CLAS) provided by Japan’s quasi-zenith satellites “Michibiki.” Therefore, even in mountainous areas or disaster sites where mobile signals are unavailable, LRTK can directly receive correction signals from Michibiki to achieve high-precision positioning. This allows continuous positioning even where internet-based base-station corrections (VRS/NTRIP, etc.) are unavailable, enhancing reliability in emergencies.

Thus, LRTK is an innovative device that maximizes the benefits of tilt-compensated GNSS while combining portability and high precision. Integrating with a smartphone improves usability, and LRTK’s one-stop capability from positioning and measurement to data utilization is a distinctive advantage.

Case studies and use cases of field efficiency using LRTK

What kinds of efficiency improvements occur on site after introducing LRTK? Here are some specific field use cases.

• Everyone can immediately act as a surveyor: In situations that used to require a specialist or heavy equipment, workers can now perform surveying on the spot with LRTK. For example, on road construction sites, supervisors and craftsmen can carry an iPhone + LRTK and instantly measure and record coordinates at needed points. With a high-precision positioning tool for each person, losses from waiting for personnel or arranging equipment are greatly reduced.

• Speeding up piling layout: For setting pile positions for bridge piers or building foundations, smartphone surveying + tilt-compensated GNSS can eliminate intermediate chalking steps. Design coordinates for piles shared in the cloud can be called up in the app, and by following on-screen guidance you can reach the exact position by simply walking to it. Since the worker’s smartphone shows “this is the pile position,” anyone can place piles without getting lost. At one site, this method simplified piling layout procedures so that even without experienced survey technicians, piles were installed with equivalent accuracy.

• Surveying in narrow or hazardous locations: Tilt compensation makes it possible to measure points that were once impossible. For instance, at cliff edges, alongside retaining walls, or across waterways—where footing is poor and you cannot place equipment directly overhead—you can insert the pole at an angle and touch the tip to the target to safely and accurately obtain coordinates. This improves survey coverage and reduces missed measurements and risky postures.

• Rapid situational assessment at disaster sites: Because LRTK is lightweight and compact, it is highly mobile for emergency dispatch. Even in large-scale disasters where heavy equipment cannot be brought in, a single LRTK unit can measure and record site conditions and share them instantly via the cloud. In fact, at disaster sites where cellular service was unavailable, LRTK used Michibiki’s CLAS signals to achieve high-precision offline positioning and quickly communicate site information to stakeholders. Where surveying was previously impossible, LRTK enables rapid data collection and sharing.

• Point-cloud scanning and as-built management: LRTK is not only for single-point surveying but can be combined with smartphone cameras or LiDAR to acquire high-precision 3D point cloud data. For example, to estimate excavation volumes on site, you can walk around while capturing images with your smartphone to generate a georeferenced point-cloud model. What used to be outsourced to specialists can now be done in-house in a short time, and the PDCA cycle for construction management can be dramatically shortened.

As shown above, LRTK’s efficiency benefits on site are wide-ranging. The key point is not only reduction of measurement labor but also the overall efficiency improvement including subsequent data processing and sharing. Field feedback includes comments such as “we can’t go back to work without LRTK” and “I always keep it in my pocket and find new uses depending on ideas,” indicating high operational flexibility.

Data sharing and measurement flexibility through cloud integration

One of LRTK’s major strengths is the data sharing and workflow flexibility enabled by integration with cloud services. With conventional surveying instruments, field-acquired data had to be brought back via USB or memory card to a PC, then imported into CAD—creating cumbersome steps. LRTK greatly simplifies these processes.

Once positioning is complete on site, you can upload data to the “LRTK Cloud” with a single tap from the smartphone app. Uploaded survey point information can be shared instantly via the internet with colleagues in the office or with clients. For example, newly measured coordinates or point clouds can be plotted on a cloud map and viewed immediately in a browser without login. Since measurements such as distances and areas between points can be performed on the cloud, there is no need to redo calculations after returning from the field.

Also, the cloud-based data sharing feature makes it easy to provide information to other companies or clients. On LRTK Cloud, select the data you want to share and generate a shareable URL with one click. Just send that URL and the configured password to the recipient, and they can view and download the data from the LRTK Cloud web interface. Supported formats include CSV and SIMA, which are convenient for industry workflows and can be directly imported into CAD or GIS. This eliminates tedious exchanges like email attachments or handing over paper drawings and ensures all project stakeholders can always reference the latest data.

Cloud integration is more than just sharing. Real-time circulation of data between the field and the office creates new flexibility. For instance, if design coordinates are pre-registered in the cloud, they can be called up from a smartphone on site for position guidance (as in the previously mentioned piling guidance case). Conversely, if as-built data collected on site is uploaded to the cloud, automatic generation of orthophotos or contour maps can be performed and shared with the office immediately. These tasks previously required expensive software or high-performance PCs, but leveraging cloud computing resources allows advanced measurement and analysis without burdening the client device.

In short, LRTK and cloud integration create a state where “measure on site and share with everyone immediately” and “necessary measurements can be done anytime, anywhere.” This is highly beneficial from a work-style reform perspective, reducing communication loss between field and office and dramatically improving the flexibility of surveying and measurement workflows.

Compatibility and potential of tilt-compensated GNSS with cloud integration

The two keywords—tilt-compensated GNSS and cloud integration—form an excellent combination for field DX (digital transformation). Each is useful alone, but combined they produce the following synergistic effects and possibilities.

• Real-time progress sharing: If numerous points rapidly acquired by tilt-compensated GNSS are shared via the cloud in real time, the entire team can immediately grasp site progress. For example, if daily embankment volumes in earthworks are measured with tilt-compensated GNSS-equipped devices and uploaded to the cloud, remote offices can confirm as-built conditions the same day. This can virtually eliminate time lags between field and office.

• Centralized data management and utilization: Positioning data accumulated in the cloud can be integrated into project-wide GIS maps or BIM models for centralized management. Overlaying precise point clouds or coordinates from tilt-compensated GNSS in the cloud makes consensus among stakeholders easier. Comparing design drawings and construction plans online helps detect rework or errors early. In the future, accumulated data could be analyzed by AI to optimize construction processes or monitor terrain changes.

• Integration with new surveying methods: Tilt-compensated GNSS + cloud makes combining with other technologies easier. For example, integration with AR (augmented reality): calling up cloud-stored design data on a smartphone and overlaying it on the real view provides an intuitive AR guide to support on-site work. Because tilt compensation ensures accurate positioning even with a tilted pole, AR overlays remain aligned with real-world objects. This enables construction and surveying support that even unskilled workers can understand intuitively.

• Expansion to machine guidance: While large sites often mount GNSS on heavy machinery, similar capabilities can be realized on small to medium sites with a smartphone + LRTK. You can create an environment where machine operators reference their own position and design lines on cloud-synced tablets. Reference points acquired with tilt-compensated GNSS can be shared in the cloud and referenced by machines, enabling flexible on-site IoT integration. Achieving machine-guidance-like precision with affordable equipment could broaden the accessibility of such capabilities within the construction industry.

Thus, tilt-compensated GNSS and cloud integration amplify each other’s strengths. In government-promoted initiatives like “i-Construction” and “ICT construction,” the use of GNSS and the cloud is a key theme. Systems like LRTK, which integrate tilt-compensated GNSS, match this trend and will likely see expanding applications.

The overall picture of simple, high-accuracy positioning with LRTK

As discussed so far, LRTK fuses tilt-compensated GNSS technology with the cloud to offer a comprehensive package for simple and high-precision positioning. The overall solution provided by LRTK consists of the following elements.

• Hardware: A small RTK-GNSS receiver that attaches to a smartphone (LRTK device). This provides tilt-compensation-capable high-precision GNSS positioning. It is portable, can be mounted on a pole or monopod as needed, runs on an internal battery for extended operation, and allows agile surveying across sites.

• Software (smartphone app): A dedicated app for iPhone/iPad processes position data received from the device in real time. It offers intuitive UI for starting/stopping positioning, saving points, switching averaging or continuous modes, taking photos with position records, AR-guided navigation, and more. The app connects seamlessly with the cloud for one-tap data sync and sharing.

• Cloud service: On LRTK Cloud, uploaded survey data is organized and stored by project. You can inspect points on maps, reproduce site conditions with a 3D point-cloud viewer, and automatically generate deliverables (plan views, cross-sections, volume calculation reports, etc.) from measurement data. URL sharing facilitates smooth external data provision. The cloud is not just a storage location but a place that immediately converts field data into valuable information.

• Workflow integration: With hardware, software, and cloud integrated, the previously fragmented flow of surveying → data organization → sharing → utilization becomes continuous. For example, you can share control point coordinates acquired by LRTK with the team in the morning, aggregate each person’s measurements to the cloud throughout the day, and compile as-built checks and reporting materials in the evening. No paper notebooks or USB devices are needed; the field and office remain continuously connected by data, which is the essence of LRTK’s simple positioning.

From this whole picture, it becomes clear that LRTK is not merely a replacement for surveying instruments but a solution that renovates the surveying workflow itself. High-precision positioning becoming accessible to everyone accelerates field DX, enabling tasks previously left to specialists or later processes to be handled in real time. In other words, LRTK’s simple, high-accuracy positioning improves not only the act of “measuring” but also the immediate utilization of measured data, transforming overall field operations.

Conclusion: Reasons to adopt LRTK for surveying

Finally, summarizing the reasons why we strongly recommend adopting LRTK based on the points covered.

By combining the efficiency and high precision of tilt-compensated GNSS with the data utilization power of cloud integration, LRTK delivers new value to surveying and construction sites. Tasks that previously required two people and a lot of time can be completed quickly by one person with LRTK. Moreover, acquired data is immediately shared to the cloud and can be used in real time by the whole team.

LRTK’s intuitive smartphone app enables advanced positioning even for non-specialists. This addresses labor shortages in the construction industry by allowing anyone to ensure required accuracy on site. Additionally, the compact, lightweight, and reasonably priced device design makes it accessible to small and medium sites and municipalities that previously hesitated to adopt expensive equipment. The ability to obtain surveying DX with reduced initial and maintenance costs is a major appeal.

Also noteworthy are the future prospects and expandability. LRTK will continue to receive feature updates, and functions like AR-assisted construction support, photo logging, and indoor positioning modes are already implemented. It is not merely a surveying instrument but a platform that continues to evolve. Adoption means not ending at the current capability but continuously receiving new features.

In summary, introducing simple surveying with LRTK enables simultaneous improvement in “efficiency,” “accuracy,” and “sharing.” LRTK enhances field productivity and safety and creates an environment where data-driven construction management is accessible to everyone. LRTK is poised to become a standard field tool. Surveyors, construction managers, infrastructure inspectors, and municipal staff alike should experience this new positioning solution. We expect that adopting LRTK for surveying will propel your field operations to the next stage.

FAQ

Q: Can accurate positioning really be achieved while the pole is tilted? A: Yes. Modern tilt-compensated GNSS devices—including LRTK—maintain centimeter-level accuracy even when the pole is somewhat tilted. Built-in IMU sensors detect tilt angles and orientation and correct the positioning data in real time. However, accuracy may degrade at extreme angles or with large motion, so using a monopod or employing short-time averaging as needed can help ensure required precision.

Q: Can LRTK be used without surveying expertise? A: Yes. LRTK is designed to be user-friendly for beginners. The dedicated smartphone app clearly displays current position and target points, and operation is intuitive with simple button controls. Coordinate system settings and calculations are automated, so non-experts can obtain accurate results. There are cases where inexperienced workers have used LRTK to set pile locations successfully without issues.

Q: How can data measured on site be shared? A: Measurement data obtained with LRTK can be uploaded to the cloud directly from the smartphone on site. Data saved in the cloud can be shared instantly via the internet with office PCs or other team members. Using the cloud’s sharing features, you can issue a URL with one click and allow stakeholders to view or download data—eliminating complicated file exchanges and ensuring everyone always has access to the latest data.

Q: Can LRTK be used in mountainous areas without cell coverage or indoors? A: High-precision positioning is possible even in areas without mobile coverage. The LRTK receiver can receive CLAS correction signals from Japan’s quasi-zenith satellite Michibiki, allowing centimeter-level accuracy from satellites alone in environments without internet. However, satellite visibility (open sky) is required. In indoor or underground locations where GNSS signals do not reach, an “indoor positioning” mode can be used: obtain a reference position outdoors once, then use IMU-based dead reckoning to continue positioning for a short period.

Q: If we adopt LRTK, will conventional surveying instruments become unnecessary? A: In many cases, LRTK can cover everyday surveying and measurement needs. It handles tasks from control point surveying to as-built management and pile guidance. However, for very long-distance precision traversing or cases requiring special high-precision control, traditional total stations and similar instruments may still be more appropriate. LRTK serves as a primary tool for field surveying, and combining it with existing equipment where appropriate will enable a more efficient and robust surveying system.