Are you missing anomalies in infrared inspections? Achieving zero misses with high-precision positional recording

Infrared camera inspections (thermographic inspections) are widely used for building diagnostics, electrical equipment maintenance, and even module checks at solar power plants. Non-contact infrared inspections that can "visualize" temperature distributions offer a major advantage in the early detection of abnormalities that are difficult to find with the naked eye. However, there is a latent issue of missed detections: "losing sight of an anomaly that was found." Even if a thermal anomaly is detected, if its location cannot be accurately identified and recorded, there is a risk that the anomalous spot cannot be pinpointed during later repairs or re-inspections. This article organizes the basics of infrared inspection and common on-site issues, and explains a solution that achieves "zero misses" by combining high-precision positional recording. We hope this provides hints for field workers and maintenance technicians to use infrared inspections more reliably and smartly.

Basic principles of infrared inspection and common on-site issues

Infrared inspection is a method that captures infrared radiation (thermal emission) emitted by objects with a specialized camera to detect temperature non-uniformities and anomalies. Its major strength is that it can non-destructively discover internal problems that are not visible to the naked eye, such as peeling or insulation defects on building exterior walls, water leaks, abnormal heating of electrical equipment, and temperature increases due to mechanical wear. It also allows safe inspection without erecting scaffolding or touching surfaces, and its efficiency in surveying wide areas in a short time is another attraction.

However, several issues have been pointed out in the operation of infrared inspections on site. Problems related to how detected anomalies are located and recorded are particularly directly linked to the risk of missed detections. Below are common problems that occur on site.

• Difficulty accurately pinpointing anomaly locations: Infrared images show where temperature anomalies are, but it is not easy to understand where those correspond in real-world space. In large factories or complex equipment, depending on shooting angle and distance, staff may later be confused about "which pipe joint is hot." Even for buildings, indicating exactly "what position on the drawing" corresponds to an anomaly shown on part of a large wall tends to rely on experience and intuition.

• Manual recording mistakes and omissions: When an anomaly is found, many sites write notes on photos or record locations and conditions in notebooks. However, relying on manual recording carries risks of "writing errors in notes or mixing up photos." If later it turns out "photo numbers do not match the equipment locations" or "the crucial anomaly location was forgotten in the notes," the valuable discovery may be wasted.

• Difficulty in rechecking and later follow-up: When repairs are performed after an inspection or when observing progress over time, it is necessary to "identify exactly the same spot that was previously detected." If records are vague, reproducing "which part previously showed a thermal anomaly" is difficult, making proper reinspection hard. Especially in equipment with many similar parts or buildings with repetitive rooms, misidentifying locations makes it easy to overlook anomalies.

Thus, while infrared inspection itself is useful, insufficient location management and information sharing can introduce risks of "missed detections" and "communication errors." So how can these issues be solved so that anomalies found by infrared inspection can be reliably captured and tracked?

Improved reproducibility and evidentiary value of infrared inspection with high-precision positional information

The key to solving the issues described above is to link infrared inspection results with high-precision positional information. If the coordinates or position of a detected thermal anomaly can be recorded accurately, the reproducibility and evidentiary value of the infrared inspection will dramatically improve.

First, regarding reproducibility: with positional information, the same location can be accurately re-examined later. For example, if during a periodic inspection six months later you have a coordinate-attached record stating, "temperature rise was observed on the north lower part of the connection box of the ○○ section, at a position ○ m (○ ft) from the wall," a new person in charge can perform a pinpoint recheck of the previous anomaly. Ensuring reproducibility makes it much easier to track temporal changes in anomalies or verify whether a problem was resolved after repair, enabling continuous maintenance.

Next, the improvement in evidentiary value. Infrared images tied to positional information have higher value as objective evidence. Compared to reporting verbally or in writing "there is an anomaly near the center of the east face of the X-story building," showing a thermographic image with coordinate data is more intuitive and persuasive to stakeholders. Especially when reporting to building owners or facility managers, images linked to specific positions on maps or drawings serve as powerful evidence for accountability. Also, clearly positioned data is more credible for later third-party verification and is useful as a record in case of trouble.

Furthermore, using positional information helps prevent inspection omissions. If you plot shooting positions and anomaly locations on a map of the inspection area, you can immediately see which parts have not yet been checked. As a result, you can create a thorough inspection plan that aims for zero oversights.

By combining precise positional records with infrared inspection in this way, you can move beyond "detecting an anomaly and stopping there" to a high-quality maintenance inspection workflow that includes "reliably tracking and correcting" issues. So how should such high-precision positional information be obtained and handled on site?

Centimeter-class positioning and automatic image tagging realized with smartphone RTK

Recently, a technology attracting attention for solving this issue is high-precision positioning using smartphone RTK. RTK (Real Time Kinematic) is a method that corrects satellite positioning (GNSS) errors in real time, dramatically improving positioning accuracy. RTK positioning using dedicated high-performance GNSS receivers has long been used in civil engineering surveying, but recently the emergence of compact RTK devices that can be attached to smartphones has made centimeter-class positioning easily achievable. By using smartphone RTK, GPS position information that used to have errors of several meters can be improved to centimeter accuracy, allowing anomalies found in infrared inspections to be recorded with almost no positional offset.

In smartphone RTK solutions, a dedicated RTK-compatible antenna/receiver attached to a smartphone works in concert with a positioning app. A characteristic feature is that you can check the current position on the smartphone screen with centimeter accuracy and acquire/record positional coordinates with a single tap. For example, when an anomaly is captured by an infrared camera, you can immediately save the coordinate of that point with smartphone RTK and tag the infrared image. Infrared images with automatically attached positional tags can be cataloged in a database along with date/time and measurement values, greatly reducing the effort and errors associated with handwritten notes.

The benefits of centimeter-class positioning on site are significant and prevent situations where "the anomaly cannot be identified later because the coordinates are off by several meters." Especially for outdoor large facilities, piping networks, or solar panel anomaly detection, a discrepancy of several meters can make it difficult to determine which component is affected, but high-precision positioning makes it easy to distinguish adjacent panels or pipes. Also, for indoor inspections, using RTK positioning outdoors to establish reference points and then determining indoor positions relatively enables applications for indoor anomaly positioning that were previously difficult.

Systems that leverage smartphone RTK are making on-site infrared inspections and positional recording seamless. Since acquired infrared images are automatically tagged with positioning data, there is no need to worry later about "which photo corresponds to which location." Field workers can enjoy the benefits of high-precision positioning without consciously handling complex equipment simply by using a familiar device: their smartphone.

The inspection process transformed by cloud sharing and history management

Once high-precision positional data is obtained, the next step is utilization. Traditionally, organizing infrared inspection results and preparing reports has largely been a manual, offline task. Assigning numbers to each photo, plotting anomaly positions on Excel or paper drawings, and compiling reports — such work is cumbersome, time-consuming, and prone to omissions. Introducing cloud sharing and history management systems can revolutionize the entire inspection process.

Specifically, infrared image data tagged by smartphone RTK can be uploaded to the cloud immediately from the field and shared with the entire team. On the cloud, each data set is visualized by being plotted on maps or drawings, allowing the office to grasp on-site anomalies in real time. This enables remote assistance such as having an off-site specialist provide immediate advice or issue instructions for additional investigation. Situational judgment that used to rely on a single field person can now be made by the whole team.

Another benefit of cloud use is history management of inspection data and automated report generation. Accumulated positional infrared inspection data can be managed as a chronological history, making past comparisons easy. Analyses such as "the area of thermal anomaly has expanded compared to last year" or "whether the same spot has recurred since the previous inspection" can be done with a single click, improving the accuracy of predictive maintenance. Additionally, services that automatically generate reports based on cloud-stored data are emerging. Photos, positional information, and comments are automatically laid out in a fixed report format, so the person in charge only needs to check and make minor adjustments. This drastically reduces the manual work of pasting images and writing text, significantly shortening report preparation time.

For example, in cases where drones conduct infrared imaging over the vast grounds of a solar power plant, services now exist that convert the obtained thermal images into orthomaps (composite aerial maps), add markers to anomalies, and allow confirmation on a tablet. Inspectors can, like with a navigation app, check their current position on the map and be guided to the relevant panel for swift repairs, making it much easier to identify defective panels that were previously difficult to locate. Using such modern cloud-based tools, you can seamlessly link the detection of anomalies in infrared inspections to reliably finding and addressing them on site.

Centralized cloud-managed data also provides peace of mind by ensuring all stakeholders share the latest information. Since people in the field, the office, headquarters, and branch offices can "discuss and decide while looking at the same information" across geographical distances, decision-making speed increases. As a result, you can build a high-quality maintenance system that not only achieves zero misses but also has no gaps in response.

Actual functions of LRTK and applications to surveying and point cloud measurement

As a high-precision positioning solution using smartphone RTK, our LRTK is also a strong tool supporting on-site DX. LRTK is a compact RTK-GNSS receiver used attached to a smartphone, and as described above, it easily achieves centimeter-class positioning. It stands apart from handheld GPS units and supports network-type RTK corrections and augmentation signals from Japan’s quasi-zenith satellite "Michibiki" (CLAS), enabling stable high-precision positioning even at sites outside communication coverage or in mountainous areas. Its small design with built-in battery and antenna allows field workers to perform survey-level positioning using only a smartphone without being conscious of special equipment.

LRTK can be applied to many other tasks beyond providing positional tags for infrared inspections. For example, it offers the following functions to comprehensively support on-site digitalization.

• Standalone positioning and simple surveying: By tapping the point you want to measure on the smartphone map screen, you can accurately record coordinates even for the installation position of a single bolt. It is useful for simple surveying tasks such as cadastral surveys and recording equipment installation positions.

• Point cloud scanning (3D measurement): Simply walking around holding a smartphone allows you to scan surrounding structures and create high-precision 3D point cloud data with positional coordinates. For example, it can quickly digitally record the current state of complex shapes such as the undersides of bridges or plant piping, and be used for volume calculations and displacement checks.

• AR-based on-site support: Design drawings and past data can be projected into space on a smartphone via AR (augmented reality), achieving accurate AR displays without positional drift. This makes it possible to visualize lines on drawings or buried equipment positions on site and verify them, or to have the smartphone guide you to invisible target points for tasks like pile driving. Stable AR that does not drift even while walking around is a feature unique to high-precision positioning.

All these functions are realized by the integration of LRTK, a smartphone app, and cloud services. Anomalies precisely recorded during infrared inspections can be uploaded to the LRTK cloud and managed in combination with point cloud data and drawings, allowing you to store an integrated digital record that combines the phenomenon of "temperature anomaly" with spatial information. By linking with other tasks, infrared inspection data can become not only a one-off report but also valuable decision-making material for future facility management and renovation planning.

Conclusion: Smart maintenance beginning with infrared inspection through high-precision recording DX

Information obtained from infrared inspections is a treasure trove for maintenance. By combining it with high-precision positional recording and cloud utilization, you can achieve not only "zero misses" on site but also transform the entire cycle from inspection to repair. Areas that used to rely on craftsman skills and intuition will be supported by digital data, promoting the elimination of person-dependence and the sharing of knowledge across the team. As a first step, why not incorporate positional information as a new perspective into your infrared inspections?

Fortunately, thanks to technological innovations such as smartphone RTK, this kind of high-precision recording DX is no longer difficult. With tools like LRTK, you can achieve smart maintenance that balances accuracy and efficiency without increasing the burden on the field. Building a system that does not leave detected infrared anomalies "found and forgotten" directly improves equipment reliability and safety. Make the latest technology your ally and spread the assurance of zero misses to your sites. Take a step toward smart maintenance that wisely leverages digital technology.