Equipment Inspections Transformed by Railway DX: Visualizing Equipment Conditions with LRTK

In recent years, the wave of digital transformation (DX) has also reached Japanese railway sites. To support safe and stable railway operations, the domain of equipment inspections is being reconsidered, and transformation through digital technologies is required. Railway companies and local governments must inspect and maintain numerous infrastructure assets daily—signal equipment, level crossings, communication cables, train safety devices, trackside lighting, and more. At the same time, on-site work remains largely analog and labor-dependent, leaving significant room for efficiency gains and technological advancement.

Challenges and Needs for Transformation in Equipment Inspections within the Context of Railway DX

Against this backdrop, the railway industry is accelerating efforts to review equipment inspection work in the context of railway DX. In particular, several issues exist with conventional inspection methods, and there are strong demands for change from the field. For example:

• Inspection results and deterioration assessments tend to rely on veteran workers’ empirical rules, leading to person-dependence

• Photo records and paper logbooks can only capture equipment conditions in two dimensions, making it difficult to grasp fine changes or three-dimensional conditions

• Compiling reports and sharing information takes time, creating information gaps between the field and the office

With an aging workforce of experienced personnel and labor shortages, it is urgent to use digital technologies to solve these problems. By advancing inspection processes through DX, it is expected that oversights and variation in judgments will be reduced, enabling objective and rapid decision-making based on data.

Limits of Conventional Inspection Records and Person-Dependence: Moving Beyond Photos, Paper Logs, and Experience

In traditional railway equipment inspections, inspectors typically perform visual checks on-site, take photos of points of interest, and write notes on paper checklists. For example, if a small rust spot or crack is found on a signal, they might photograph it and write a note in a paper log such as “minor rust (monitor)”. While simple, this method has limitations in terms of information accuracy and shareability.

First, the amount of information in photos and notes is limited. Photos only show part of the scene from the taken angle, and it is difficult to accurately grasp the degree of tilt or deformation from two-dimensional images. Paper records cannot vividly recreate the on-site conditions when reviewed later, forcing reliance on memory in some cases.

Second, records and judgments were dependent on individual inspectors. Even when inspecting the same equipment, a veteran may not miss anomalies while a less experienced inspector might overlook them. The threshold for what constitutes “minor” rust varies by person, so judgment criteria are subjective. As a result, inspection quality can vary, and there is a risk that veterans’ tacit knowledge will not be passed on to newcomers.

Moreover, inspection records managed in paper logs or Excel files posed problems for in-house sharing and utilization. Inefficient communication often occurred, such as field staff searching archives for photos and notes to explain conditions to head office managers. By the time consolidated inspection reports were submitted, field details were sometimes forgotten. Moving away from these traditional methods and introducing a system in which anyone can record objective data in the same way is the first step in railway equipment inspection DX.

High-Precision Positioning and Point Cloud Scanning with LRTK: Spatially Recording Equipment Information

A new technology attracting attention for accurately recording field conditions is smartphone-based high-precision positioning + 3D scanning. “LRTK,” provided by Lefixea Co., is a solution consisting of a small RTK-GNSS receiver that can be attached to a smartphone and a dedicated app; with it, anyone can easily obtain position information with centimeter-level precision (cm-level accuracy (half-inch accuracy)). By combining the smartphone’s built-in camera or LiDAR sensor, you can scan on-site equipment and record it as point cloud data (digital data that represents the three-dimensional shape of an object with a large number of points).

LRTK’s strength lies in its high positioning accuracy. Normally, smartphone GPS can have errors of several meters (several m (several ft)), but LRTK uses the RTK method with Japan’s satellite positioning augmentation services to measure current position with errors of only a few centimeters or less (a few cm (a few in) or less). For example, if you scan equipment installed at a level crossing, you can accurately record “which track at which point had which condition” in a global coordinate system. Because inspection data are tied to absolute position and time information, you can spatially reproduce “when, where, and how” something was at a later date.

Point cloud scanning with LRTK is also simple in procedure. Attach the receiver to the smartphone with a single touch, configure the correction information reception in the dedicated app, and then just walk around the inspection target with the smartphone in hand. By walking while pointing the camera at the scene, you can obtain colorful 3D data of the equipment surroundings with millions of points in a matter of minutes. No expensive laser scanner or specialized skills are required, and on-site staff can intuitively perform the measurements themselves. For example, you can preserve a digital record that faithfully reproduces fine details such as the tilt of a signal pole or cracks in its foundation. Once point cloud data are created, it becomes easy to check “what that part looked like” later from the office or to hand the data to another staff member for analysis. The “spatially recorded” equipment information conveys the field with reproducibility that paper notes cannot match.

Visualizing Condition Checks and Design Verification with AR Overlay

Another notable feature of LRTK is the ability to display acquired 3D data on-site as AR (augmented reality). Once scanning is complete on a smartphone, switching the app’s display mode lets you overlay the recently acquired point cloud data or 3D models onto the real-world scene. Because RTK enables precise alignment, the digital data do not shift away from the actual object when the smartphone is moved, matching perfectly as if placing a transparent model on the site.

This AR overlay function makes instant on-site verification dramatically easier. For example, displaying a scanned signal’s point cloud in AR might make subtle tilts visible through the 3D data that were not noticeable to the naked eye. By overlaying pre-prepared design models or data from past inspections onto current conditions, you can intuitively check “is it installed according to the design?” or “has anything changed since the last inspection?” Being able to confirm 3D data on the spot allows flexible responses such as performing additional scans immediately if something was missed.

AR-based visualization is powerful not only for on-site workers but also for explaining conditions to stakeholders in remote locations. Sharing the smartphone screen showing the real object plus digital information makes situations that are hard to convey with words or flat diagrams immediately clear. For example, instead of verbally saying “this bolt is slightly loose,” showing the bolt highlighted in AR enables inexperienced staff or supervisors to intuitively grasp the problem’s location. Rather than trial-and-error comparing the field, drawings, and memory, you can verify answers on the smartphone screen—this is a major advantage of AR use.

Faster Sharing, Analysis, and Decision-Making via the Cloud

Point cloud data and geotagged photos (photos with position and orientation information) acquired with LRTK can be uploaded directly from the field to the cloud. By aggregating data on a cloud platform, you create an environment where you can re-experience the field’s three-dimensional information from the office. Without installing specialized software, you can view and measure 3D point clouds via a web browser, allowing managers and designers to immediately confirm details on their PCs.

Cloud sharing smooths information coordination between the field and the company. For example, if someone reports from the field “I found what looks like a crack in the level crossing foundation,” everyone involved can objectively discuss the crack’s location, size, and depth by viewing the 3D data in the cloud. Previously, the field representative would send photos by email and the recipient would have to imagine the situation from two-dimensional images, but with point cloud data you can view the scene from different angles in three dimensions, reducing misunderstandings like “it wasn’t what I expected.”

Using the cloud also makes centralized data management and analysis easier. If all past inspection data are stored in the cloud, you can quickly retrieve them by date or location, and use advanced approaches like opening multiple sites’ data simultaneously for comparison. In the future, this could be applied to analyzing inspection trends to detect signs of failure. Most importantly, because information obtained in the field can be shared in-house the same day and reflected in decision-making, the planning of emergency measures and repairs becomes dramatically faster.

Improving Work Quality by Turning Records into Assets and Passing on Inspection Knowledge

One of the greatest benefits of DX is the assetization of inspection records. Traditionally, inspection know-how and judgment criteria tended to be stored in the minds of veteran individuals. However, digital inspections using LRTK accumulate equipment conditions as objective data, making them organizational assets.

For example, if you record point cloud data for a signal facility every year, you can quantitatively grasp its aging changes. You can visualize temporal changes such as “rust has expanded by 10% since last year” or “tilt has increased by ◯ degrees compared to the previous inspection,” making it easier to determine the appropriate timing for repairs or replacement. New employees can learn what points seniors paid attention to by tracing past data in 3D. Nuances that are hard to convey in paper reports are easier to share through 3D visual information, aiding the transfer of inspection knowledge.

When records are digitized and systematized, another advantage is that work quality is easier to maintain even when personnel change. In a person-dependent state, cases often arise that “only the previous person knows,” but after DX, materials remain that allow anyone to make the same judgment, enabling maintenance with high reproducibility across the organization. In other words, you can build work processes that are reproducible regardless of experience.

Moreover, accumulated data can be used in the future for AI analysis, enabling predictive maintenance and optimization of inspection schedules. The digital assets created by DX will form the foundation for new analyses and services, contributing to the further advancement of railway equipment management.

Implementation Effects from the Client Perspective and a Phased Deployment Plan

So, when promoting railway equipment inspection DX in practice, what effects and deployment plans can be envisioned from the client’s (railway companies and local government officials’) perspective? On the effectiveness side, you can expect cost reductions and improved safety from streamlining on-site inspection processes. Automating and simplifying record-keeping that used to rely on paper and manpower shortens work time and broadens the scope that can be covered despite staffing shortages. Also, if data-driven judgments reduce the risk of missing serious defects, there will be substantial safety benefits in preventing accidents and avoiding service interruptions.

Furthermore, as data utilization progresses, maintenance planning optimization is expected. If you can understand deterioration trends for each asset from data, you can schedule part replacements and renovations without waste, and shift to condition-based preventive maintenance to reduce total lifecycle costs. The DX initiative itself helps cultivate a digital culture within the company and can be an attractive workplace reform for younger talent—this is an additional benefit.

For implementation, rather than digitizing all assets and processes at once, a phased rollout is recommended. First, to let the field experience the usefulness of LRTK inspections, adopt it experimentally for a portion of a line or certain assets as a model case. For example, choose one level crossing that requires attention due to aging, and compare it with conventional methods. Have field staff actually scan with a smartphone and LRTK so they can experience the ease of data recording and the information obtained. Sharing those results internally will deepen understanding of the data’s usefulness and smooth horizontal expansion to other locations.

When deploying in phases, it is also important to carefully collect field feedback and reflect it. Gathering positive comments like “I was initially confused, but using it shortened my work time” or “it’s easier to explain inspection results to my supervisor” will raise internal motivation for DX promotion. If issues are found, they are easier to correct at a small-scale introduction stage. By taking these steps, the ideal is to eventually establish digital inspections as standard practice across the entire railway company.

Start with One Location: Experience Inspection DX with LRTK Simple Surveying

DX of railway equipment inspections is not something completed overnight. However, that doesn’t mean it has to be complicated. The key is to “start by trying one location.” Fortunately, smartphone-based solutions like LRTK have low initial barriers to introduction and can be used in the field without special equipment investment or advanced training.

For example, at the next regular inspection, why not trial LRTK measurement at a single level crossing? Scan the placement and condition of equipment with a smartphone in hand and review the resulting 3D data. After returning to the office, if you can view that data in the cloud with your supervisor and colleagues and feel “so that’s what it was like on-site,” you will be able to appreciate the value of digital inspections. Field veterans have also reported that “seeing it in 3D makes it easier to share the situation” and “there is reassurance in having the data recorded.”

By accumulating such small successes, momentum for DX promotion will accelerate. Taking one step beyond the era of paper forms and cameras alone, starting digital inspections with simple surveying using LRTK can be a valuable first step toward the future of railway equipment management. Please try this method on-site at least once—the ability to accurately visualize “when, where, and how” things were in the field will surely become the trigger that opens the path to safe and efficient railway DX.