The practise of developing three-dimensional models from three numbers of two-dimensional orthographic views is known as 3D reconstruction in civil engineering. When used in building construction technologies, the 3D reconstruction process has both advantages and limits. In terms of application, this building construction technique is one-of-a-kind. This method is based solely on drawing interpretation and makes use of information and their combination. This is done in such a way that the engineering components may be recognised and reconstructed using the reduced descriptions provided in the appropriate engineering drawings.
3D Reconstruction Technique in Construction
In the construction sector, it is common practise to use a two-dimensional drawing to describe a three-dimensional construction component. Even though there are CAD software products that allow users to generate 3D components, it is still common practise to bring 2D drawings. In some cases, a 3D component can be easily comprehended by sketching its corresponding 2D representation or sectional drawing. The 2D orthographic images provide a sense of the 3D components, as discussed previously. With the help of an example, this may be readily explained:1st example:The quantity surveyor must mentally reconstruct the 3D models so that he does not overlook any important quantities when performing quantity surveying. This will allow you to.
As a result, a computer software for measuring quantities must be able to automatically reconstruct 2D orthographic views into corresponding 3D models before performing the measurement. Techniques for 3D reconstruction have a long and illustrious history. The study of 3D reconstruction virtually began in the 1970s. Following that, further investigation was conducted in order to arrive at a suitable solution. The majority of the algorithms created could only convert a two-dimensional picture into three-dimensional planar objects. The reconstruction of 3D elements of curves and incorrect shapes using 2D orthographic views was extremely difficult.
3D Reconstruction Algorithm Development
Because the aspects mentioned affect the development of algorithms, there are a few major tasks that should be followed to build the 3D model from the respective 2D orthographic views:Step 1: The first step is to convert the two-dimensional points into their corresponding three-dimensional vertices. Step 2: The next step is to produce the 3D element’s edges from the 3D vertices that were created in : After obtaining the 3D vertices and 3D edges, the development and fabrication of faces is the following step. The 3D borders are used to create this.Step 4: The 3D polyhedron is created from the developed and constructed 3D faces.
Another challenge in the development of a 3D reconstruction algorithm is the engineering or construction drawings’ characteristics. Many components can be included in construction designs, including steel reinforcement bars, which are difficult to depict in their real size in a 2D model. As a result, in 2D, the designers use simplified figures to make them easier to express. With the help of the following example, this may be clearly illustrated.Explanation 2: Reinforcement bars that are attached with a text stating the number and size of the corresponding bar are represented by a single line. From their 2D orthographic views, these simplifications are extremely challenging to rebuild into a 3D model.
3D Reconstruction Process
Longguet-Higgins demonstrated in 1981 that if two photographs of the same scene contain eight points that are located in both projections, the respective structure may be determined from the eight pairs of corresponding image coordinates. This is one of the studies that paved the way for 3D reconstruction in the future. The use of 3D reconstruction in the building sector is a relatively new concept that is quickly gaining traction.Process of 3D Reconstruction In a broad sense, the 3D reconstruction process is depicted in the flowchart below.
The steps, with the exception of the first, are only used or stated when a 3D reconstruction technique is used. The first phase is also known as the input step.The photographs are captured with the use of cameras in this step. Depending on the application, the camera can be calibrated or uncalibrated. Cameras that have been calibrated are used in the majority of research projects and case studies.The determination of significant spots in a particular image is required for feature recognition. The extraction is carried out via a set of algorithms known as feature detectors. These are rated based on how repetitious they are and how much information they include.The ability of the feature detector to determine the same spot in different images is referred to as repeatability.
Conclusion -3D Reconstruction Technique
The 3D reconstruction technique is an example of how trustworthy computer vision-based algorithms may be used to solve real-world problems. Quantity analysis and disaster analysis of civil constructions are both benefiting from 3D reconstruction approaches. FIT3D and Autodesk 123D Catch are two 3D reconstruction toolkits that could be beneficial. Researchers using the AUTODESK 123D got better results than those using FIT3D. The Autodesk 123D is capable of self-calibration. This programme also includes user-friendly tools for editing and viewing the 3D model. The work is made easier by the 3D reconstruction, which only requires a laptop or computer, modelling software, and a digital camera.
The following are the conditions that must be met in order to do the best reconstruction task:Select the Correct Methodology Before performing the overlaying of the images, plan the locations where the photos will be taken.A reference item must be put whenever any obstruction covers an important aspect of the construction.
Damage inspection and evaluation, as well as construction monitoring, have been substantially facilitated by three-dimensional (3D) reconstruction technology based on computer vision. However, it has a number of flaws in terms of implementation. In this research, a new approach of 3D reconstruction is provided for the geometrical properties of building photographs. The absolute size of the point cloud model can be determined by normalising the 3D-reconstructed point cloud model so that its length, width, and height are parallel to the world coordinate system’s coordinate axis. This system, as opposed to the traditional one, can retain a higher level of accuracy. The theoretical underpinning of the technique is established in this study, and steps for implementation are provided using digital image processing technology. Following the analysis of the data.
3D Reconstruction Technique
Because developing and changing a complex 3D architectural building in 3D space is challenging, 2D drawings are generally a more effective design method. However, it is important to transform 2D architectural designs to 3D models for a variety of applications such as quantity surveying and visualisation. We offer a new method for accurate 3D reconstruction from real-world architectural drawings in this research. Under the supervision of semantics and prior domain knowledge, the approach combines and normalises architectural information spread across many drawings and tables. Quantity surveying, construction, and 4D modelling can all be done with the reconstructed detailed 3D building.
Logo of Air pix showcase 3D map generating that is accurate and high-resolution for any building site 3D construction models can be used for a variety of applications, including urban planning, environmental modelling, mapping, tourism, and smartphone navigation. The key element of city modelling is automatically generating building models in the form of 3D CAD representations, which is a difficulty for many academics.3d-construction Introduction The use of unmanned aerial vehicles (UAVs) to scan the landscape yields high-quality geometrical data. It is useful for the reconstruction of 3D things such as buildings due to its high density and geometrical precision. 3D designs are an excellent approach to visualise the object’s three dimensions. 3D models will be generated automatically on all of your maps.3D Building Construction Techniques Given the active techniques, i.e. range information methods.
In computer vision and computer graphics, 3D reconstruction is the process of capturing.
Reconstruction allows us to gain insight into qualitative features of the object.
The goal of image-based 3D reconstruction is to infer the 3D geometry and structure.
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