Dramatically Streamline Floor Plan Creation with Point Cloud Data! Reduce Work Time with the Latest Technology

Table of Contents

• Introduction: Challenges in creating plan drawings and the need for efficiency

• Conventional methods for creating plan drawings and their limitations

• Innovations in point cloud surveying through cutting-edge technology (enabling single-person surveying)

• Steps to create plan drawings from point cloud data

• Effects and benefits of leveraging point cloud data

• Future prospects: Plan drawing creation evolving with AI and automation

• Bonus: A beginner's guide to simple surveying with LRTK

• FAQ (Frequently Asked Questions)

Introduction: Challenges in Creating Plan Drawings and the Need for Efficiency

In construction and infrastructure maintenance sites, plan drawing creation is indispensable for construction planning and as-built management. However, creating accurate plan drawings on site currently requires a great deal of time and effort. Traditionally, survey instruments were used to measure each point on site one by one, and drawings were manually produced based on those coordinates. Such work requires specialized skills and manpower, placing a heavy burden on an industry already suffering from a chronic labor shortage. Moreover, creating drawings that reflect current conditions in detail requires a vast number of survey points, but traditional methods tend to be inefficient.

In recent years, the construction industry has been experiencing an aging workforce and a shortage of successors, requiring sites to be operated efficiently with limited personnel. One solution attracting attention is the streamlining of surveying through digital technologies. The Ministry of Land, Infrastructure, Transport and Tourism is also promoting the adoption of ICT technologies through initiatives such as *i-Construction* (i-Construction), and on-site DX (digital transformation) cannot be delayed. In this article, we introduce how to dramatically streamline the creation of plan drawings by utilizing point cloud data and the latest surveying technologies. We lay out the conventional challenges and provide a detailed explanation of the solutions and benefits offered by the latest technologies, as well as concrete procedures and future prospects.

Traditional methods for creating plan drawings and their limitations

In the past, creating plan drawings typically involved time-consuming procedures. In a typical conventional method, a two-person team works using surveying instruments such as a total station. One person sets up the instrument and sights, while the other stands at a distant point holding a staff (leveling rod) to mark the survey point. Each point on site is observed one by one; those coordinates are later entered into CAD software, connected with lines, and the plan drawing is produced.

However, numerous limitations of this method have been pointed out.

• Human labor and time burden: Two-person surveying requires effort from preparation to teardown, and when wide areas or many measurement points are needed it can take a whole day or more. On large sites, surveying alone can often take several days to several weeks. Spending long hours surveying at each site sometimes caused other tasks to be squeezed, putting pressure on the overall schedule.

• Accuracy and oversights: Because measurement points are selected and measured by people, gaps inevitably occur between points and the details of complex terrain or structures cannot be fully captured. There is also a risk of human error (misreading, recording mistakes), and if missed measurements are discovered later it becomes necessary to return to the site and re-measure. These issues led to operational inefficiencies and created a risk that the finished drawings would contain omissions or inaccuracies.

• Equipment constraints: Conventional surveying equipment is large and heavy, requiring time to set up tripods and perform precise mounting. Achieving high accuracy particularly demands careful setup, which reduces mobility. In confined or uneven terrain merely setting up the equipment was a struggle. Furthermore, operating the equipment requires skill, making it difficult for newcomers and requiring specialized knowledge to handle problems.

Thus, labor-dependent surveying has inherent limits in time and effort, and on site we had no choice but to structure workflows assuming that creating plan drawings would take time. However, as the entire industry began demanding productivity improvements, we could not leave this inefficiency unaddressed. This led to the emergence of a new surveying approach that leverages digital technologies.

Innovation in Point Cloud Surveying through the Latest Technology (Enabling Single-Person Surveys)

Point cloud data refers to a collection of countless points in three-dimensional space, with each point containing (X, Y, Z) coordinates. When a subject is scanned using a laser scanner or camera-based surveying (photogrammetry), the subject’s shape is recorded as a collection of points. Although it appears like a photograph when displayed on a computer, its true form is an enormous cloud of points (a point cloud). By utilizing this point cloud data, measurement points that were traditionally picked up by people can be acquired across an area all at once, enabling the as-built shape to be captured in detail as it truly is. The latest digital surveying technologies have made it possible to acquire these point clouds quickly and easily.

Among these, particular attention is being paid to the use of mobile devices that enable a single person to carry out surveying: 一人で測量可能なモバイル端末の活用. Recent smartphones and tablets have appeared equipped with high-performance cameras and LiDAR sensors (3D scanning capability using light). For example, a certain smartphone released in 2020 came with LiDAR as standard, allowing a single device to function like a 3D laser scanner. This trend has spread to job sites, and under the Ministry of Land, Infrastructure, Transport and Tourism’s i-Construction initiative, measurements using smartphones have begun to be adopted for as-built management on small-scale sites. With smartphone apps, you can scan the surroundings simply by walking around and pointing the device, making it possible to obtain point cloud data. The operation is also intuitive, almost like a game, so even new staff without surveying qualifications can handle it after a short practice. "If it can be measured with a smartphone, let's give it a try" — adoption is spreading especially among younger generations, and the surveying style on sites has begun to change significantly.

Furthermore, not only smartphones but drones (unmanned aerial vehicles) and dedicated 3D laser scanners also demonstrate great power in point cloud acquisition. In photogrammetry using drones, by photographing the entire site from the air and converting the images into point clouds with software, you can obtain wide-area terrain data in a short time. Also, if a drone is equipped with a small laser scanner, it can acquire high-precision point clouds including areas that are difficult to capture with photos, such as the ground under trees. Using terrestrial 3D laser scanner equipment, you can perform stationary 360 degrees laser measurements at once and acquire detailed data on the scale of millions to hundreds of millions of points in a short time. Surveys of complex terrain and structures that were difficult with conventional methods can now be performed non-contact and in a short time thanks to these latest technologies.

What is particularly groundbreaking is the combination with RTK (Real-Time Kinematic) positioning technology. RTK-GNSS is a method that corrects satellite positioning errors in real time to achieve positioning accuracy of several centimeters. Traditionally, surveying instruments equipped with this RTK capability were very expensive and large-scale, but now palm-sized receivers have appeared. For example, by using a small RTK-GNSS receiver that can be attached to a smartphone, the smartphone itself “transforms” into a surveying instrument capable of high-precision positioning. In solutions like the smartphone surveying system "LRTK", by attaching a small receiver with an integrated antenna to a smartphone and launching a dedicated app, anyone can immediately start RTK surveying. Because measurements can be made by combining high-precision GNSS positioning with the smartphone’s camera and LiDAR scans using a device that weighs only a few hundred grams, one person simply walking while holding a smartphone in one hand can complete high-precision 3D measurements on site.

This new surveying approach using mobile devices + RTK brings about a major shift from the conventional "two-person, long-duration" method to a "one-person, short-duration" method. For example, when surveying a development site on the scale of several hectares, work that traditionally took about 3 days with a total station has been reported to be completed in about 2 days with a terrestrial laser scanner, and in about half a day with drone photogrammetry. In one experiment, by using a drone-mounted laser scanner, wide-area data acquisition was completed in one-sixth of the time required by conventional methods, shortening the overall operation to less than half the original period. There are also reports that a site survey that previously took two people three hours could be done by one person in a short time with a 3D laser scanner, making overwhelming time savings and labor reduction a reality. With the introduction of the latest technologies, the process up to the creation of plan drawings is undergoing a significant transformation.

Procedure for Creating Floor Plans from Point Cloud Data

So, how do you actually create a floor plan from the vast amount of acquired point cloud data? To translate three-dimensional survey data into two-dimensional drawings, the following general steps are taken.

• Acquisition and Upload of Point Cloud Data: Point cloud data measured on site is imported from the corresponding equipment or app to a PC or a cloud service. For example, in LRTK systems, point cloud data captured with a smartphone is automatically uploaded to the cloud on site. For drones or laser scanners, data is transferred to a PC via an SD card or communication link and then loaded into specialized software or the cloud.

• Point Cloud Data Cleaning and Preparation: Acquired point clouds may contain noise (unwanted points) or coordinate misalignments. Perform preprocessing on dedicated software—such as removing unwanted points and aligning coordinates (registering multiple scans)—to obtain accurate point clouds. Convert to a ground coordinate system or adjust scale as needed. Services like the LRTK cloud automatically perform position corrections, reducing effort.

• Tracing Elements to Be Drafted: On the point cloud, draw the lines and shapes you want to represent as a plan. For example, trace curb lines, site boundary lines, and building outlines by drawing line segments or polylines with a mouse to follow the point cloud. Because point clouds depict the as‑built condition almost like a photograph, you can create drawing drafts simply by tracing contours on the screen. Recent point cloud processing software and cloud services include functions to draw lines and shapes directly on the point cloud, enabling one-stop drawing creation without switching to CAD software. Line-drawing work that once required skill becomes straightforward on point clouds because you can intuitively “trace what you see.”

• Generation and Editing of Drawing Data: Using the traced line and shape data created on the point cloud, generate CAD-format plan drawing data. Many programs support export to common CAD formats such as DXF and DWG, allowing direct editing and finishing in other surveying CAD software. During drafting, you can make use of elevation information to draw contours, and it is also easy to extract building elevations and cross sections as needed. In other words, a single acquired point cloud lets you freely create various 2D drawings.

• Use and Sharing of Deliverables: The completed drawing data is used for submission to clients and for in-house design work. If you also save the point cloud itself as a 3D model, you can later check any missed measurement points or use it for other purposes (for example, construction simulation or progress management comparisons). When the data is on the cloud, you can share it immediately with stakeholders over the Internet. If you upload the data right after measuring on site, by the time you return to the office supervisors and colleagues can view the point cloud and drawings, enabling rapid review and decision-making.

That's the general flow. What used to be a procedure of recording numbers in a field notebook and drafting drawings back at the office can now be handled entirely digitally in the field, from data capture to cloud storage and drawing creation. This seamless flow creates real-time capability, dramatically speeding up the reflection of current conditions in plan drawings.

Effects and Benefits of Using Point Cloud Data

The use of point cloud data enabled by the latest technologies brings significant benefits not only to the creation of plan drawings but to the entire on-site surveying process. The main effects can be summarized as follows.

• Dramatic time reduction: The biggest benefit is a dramatic increase in work speed. As mentioned above, there are cases where large-scale surveys were reduced from several weeks → several hours, so the impact of introducing point cloud surveying is overwhelming. Not only do on-site survey tasks finish in a short time, but data processing and drawing production are also increasingly automated and streamlined, leading to overall construction schedule reductions. For example, in a verification in Kashiba City, Nara Prefecture, the creation of plan and cross-section drawings that previously took 17.2 person-days was completed in 10.3 person-days by utilizing point cloud data, achieving about 46% efficiency improvement. Time savings directly translate into labor cost reductions and more leeway to meet schedules, thereby contributing to the competitiveness of the entire project.

• Improved accuracy and comprehensiveness: Point cloud surveying captures the shape of objects with millions to hundreds of millions of points, enabling a very precise and comprehensive understanding of the current conditions compared to traditional methods that measure only specific points. With properly calibrated high-precision equipment, point cloud data errors can be kept on the order of millimeters to several centimeters (mm to in), allowing almost complete reproduction of the existing terrain. When data are precise, coordinate transcription errors and oversights during drawing production are less likely to occur, resulting in higher-quality finished plans. Also, once 3D data are acquired, you can freely extract 2D plans or cross-sections as needed later, eliminating losses such as “we forgot to measure that, so a re-survey is required.” Utilizing such high-precision, high-coverage data thus helps reduce design errors and avoid additional investigations.

• Improved safety: A major advantage of point cloud surveying is that it can be performed non-contact. Surveys can be conducted remotely with lasers or cameras in dangerous slopes, areas at risk of collapse, or roads with heavy traffic that are difficult to access. Reducing the need for people to enter hazardous zones contributes to worker safety. Also, because measurements can be completed quickly, the duration of road closures can be shortened, reducing the impact on the surrounding area. In other words, the spread of digital surveying contributes not only to efficiency but also to improvements in safety management.

• Labor saving and response to workforce shortages: Intuitive tools that can be operated by a single person have made it easier for not only veterans but also newcomers and engineers from other disciplines to participate in surveying tasks. There are increasing cases where site staff themselves can perform measurements without relying on specialized operators, increasing flexibility in staffing plans. Long hours of heavy labor and tedious manual work are reduced, easing the burden on workers and improving working conditions. The effects of reduced staffing requirements and lighter workloads are expected to help alleviate chronic labor shortages.

• Data sharing and improved communication: Point cloud data enable visual information sharing as 3D models. Site conditions that were hard to convey with drawings alone become immediately apparent when viewing a point cloud model. Sharing a 3D as-built model among contractors, designers, and clients accelerates decision-making and reduces rework caused by misaligned understanding. Furthermore, if data are shared on the cloud, stakeholders can review the same current-state data remotely for meetings, improving communication efficiency.

In this way, by leveraging point cloud data and the latest technologies, the process of creating plan drawings is being radically transformed. Tasks that once required enormous effort and time have been streamlined and accelerated through the adoption of digital tools, and smart construction that does not rely on people is beginning to become a reality. By smoothly linking surveying and drafting, reflecting current site conditions, which used to involve time lags, has become possible almost in real time. This is a groundbreaking advance that goes beyond merely shortening work time and cutting costs: it also leads to faster on-site decision-making and improvements in construction quality and safety.

Future prospects: Plan drafting evolving through AI and automation

Advances in digital surveying technologies will further evolve the workflow for producing plans. Even now, advanced point cloud processing software includes features that automatically detect the edges of terrain and structures and convert them into line drawings, and attempts are beginning to appear for AI to generate BIM models (3D design models) from photographs and point clouds. In the future, AI-based automatic drafting may become more practical, and we may see an era in which software instantly generates floor plans and elevations from scanned data.

Furthermore, point cloud data is expected to be used not merely for drawing creation but increasingly as a digital twin (a virtual space that serves as the twin of reality). By storing the acquired as-built point clouds in the cloud and leveraging them for as-built control during construction and for maintenance management, they will contribute to efficiency across the entire construction lifecycle. As site digitization advances, all stakeholders will be able to collaborate while always referring to the latest as-built data, making it easier than ever to prevent construction errors and ensure quality.

That said, even as of the mid-2020s, many sites still require two-dimensional drawings (plan views and longitudinal and cross-sectional drawings, etc.) as deliverables. However, the process of creating those drawings is clearly being innovated. Rather than humans measuring points by hand and drafting drawings, the practice of semi-automatically generating drawings from high-precision data acquired by computers is becoming widespread. This enables maintaining a high level of accuracy and reproducibility of deliverables while compensating for the decline in experienced personnel. As AI technologies and automation mechanisms are further refined, it is expected that drawing production will become faster and more accurate than ever before. The field of plan drawing production is truly in the midst of a "surveying revolution" driven by digital technology.

Bonus: A Beginner's Guide to Simple Surveying with LRTK

If you've read this far, you might be interested in the latest surveying techniques that utilize point cloud data. Finally, we will briefly introduce LRTK, a simple high-precision surveying system that uses a smartphone and a compact RTK receiver. With LRTK, anyone can easily start conducting single-person surveys as soon as today.

You only need to prepare 3 things.

• High-performance smartphone (a device that runs the point cloud measurement app)

• Compact GNSS receiver for LRTK (a high-precision GPS device attached to and used with a smartphone)

• Dedicated LRTK app (installed on a smartphone; used in conjunction with cloud services)

Once setup is complete, all you need to do on site is walk to the location you want to measure while holding your smartphone. For example, if you want to capture the position of a boundary line or a structure, simply bring the smartphone to that point and tap the button on the screen to record the coordinates of that location. If you want to 3D-scan a wide area, just walk around holding your smartphone up, and it will automatically capture the surrounding terrain and structures as point clouds. No complicated operations are required at all, and when you finish measuring you can upload the data to the cloud from the app with one click. The measurement results (point cloud) are displayed on the smartphone screen on the spot, and simple analyses such as volume calculations and distance measurements can be performed immediately.

Even if it's your first time using it, no difficult setup is required beforehand. If you follow the app's guide you'll master the basic operations in minutes, and you can use it intuitively even without surveying expertise. The traditional ordeal of carrying heavy equipment for hours is completely gone, and the ease of being able to quickly take measurements with just your smartphone whenever the idea strikes is revolutionary. First, try surveying with LRTK in a nearby field and be sure to experience its convenience and accuracy for yourself.

Even alone, with just a smartphone, you can start high-precision on-site measurements today. Why not have your site take a step toward digitization with simple surveying using LRTK?

FAQ (Frequently Asked Questions)

Q: What is point cloud data? A: Point cloud data is a large collection of points acquired by laser scanning or photogrammetry. Each point includes XYZ coordinates (positional information), and the shape of the object is represented by countless points. When a point cloud is visualized, the object's 3D shape is reproduced, and from this you can create plan views and 3D models.

Q: How does using point clouds make creating plan drawings more efficient? A: The main reason is that a single measurement can record the entire site at high density. You no longer need to pick up survey points one by one as before; for example, if you scan all around a building or site you can acquire data that covers even fine details. Because you can later trace the required lines on the point cloud to generate drawings, surveying→drafting time is greatly reduced. It also reduces human error and missed measurements, and cuts down on the number of additional site visits.

Q: What equipment and preparations are needed for point cloud surveying? A: There are several options depending on the purpose and scale. Typical ones are stationary 3D laser scanners, aerial drones (photogrammetry or LiDAR-equipped), and smartphone + compact measurement devices. If you need large-scale and high accuracy, choose laser scanners or RTK-capable drones; if maneuverability is more important, choose a smartphone with a GNSS receiver (for example LRTK). All of these require a computer or cloud service and analysis software for post-processing the measured data, but recently systems that automatically process via cloud integration have emerged.

Q: Can you use these latest surveying technologies without specialized knowledge? A: Yes, compared with conventional methods they are designed to be significantly easier to use. Smartphone-app-based point-cloud measurement tools have intuitive UIs and simple operating procedures, so even those with limited surveying experience can use them after a short training period. In practice, more and more inexperienced younger staff are being assigned to handle smartphone measurements on site. Also, manufacturers and service providers often provide extensive support and training, so beginners can adopt them with confidence.

Q: Can the accuracy of floor plans created from point cloud data be trusted? A: If the point cloud data are acquired with appropriate equipment and procedures, the accuracy is very high and can be trusted. When high-performance laser scanners or RTK-GNSS are used, errors can be reduced to the order of several centimeters (several cm; roughly a few in) to millimeter levels (mm; roughly 0.04–0.39 in). In other words, it can capture the as-built condition with accuracy equal to or better than traditional manual surveying. However, simple measurements using only a smartphone can sometimes produce errors on the order of several tens of centimeters (several tens of cm; roughly 4–35 in), so when high precision is required it is advisable to combine RTK corrections or corrections using installed targets. Drawings produced from properly calibrated and processed point clouds can achieve accuracy sufficient for practical use.

Q: What is LRTK? A: LRTK is a single-person surveying system composed of a compact GNSS receiver that can be attached to a smartphone and a dedicated app. It supports Real-Time Kinematic (RTK) technology, allowing anyone to easily perform centimeter-level (cm level accuracy, half-inch accuracy) high-precision positioning and point cloud measurement using a smartphone. It is a revolutionary solution that brings high-precision surveying—previously requiring specialized equipment—to smartphones, and it is designed so that even those without surveying experience can operate it. With LRTK, you can perform on-site rapid surveying and site plan creation without heavy equipment or complex operations. More details are available on the official website and in documentation, so if you're interested, please take a look.