Document Type
Article
Publication Date
12-2022
Publisher
American Society of Civil Engineers (ASCE)
Source Publication
Journal of Architectural Engineering
Source ISSN
1076-0431
Original Item ID
DOI: 10.1061/(ASCE)AE.1943-5568.0000564
Abstract
This paper presents an automated as-is façade modeling method for existing and historic high-rise buildings, named Scan4Façade. To begin with, a camera drone with a spiral path is employed to capture building exterior images, and photogrammetry is used to conduct three-dimensional (3D) reconstruction and create mesh models for the scanned building façades. High-resolution façade orthoimages are then generated from mesh models and pixelwise segmented by an artificial intelligence (AI) model named U-net. A combined data augmentation strategy, including random flipping, rotation, resizing, perspective transformation, and color adjustment, is proposed for model training with a limited number of labels. As a result, the U-net achieves an average pixel accuracy of 0.9696 and a mean intersection over union of 0.9063 in testing. Then, the developed twoStagesClustering algorithm, with a two-round shape clustering and a two-round coordinates clustering, is used to precisely extract façade elements’ dimensions and coordinates from façade orthoimages and pixelwise label. In testing with the Michigan Central Station (office tower), a historic high-rise building, the developed algorithm achieves an accuracy of 99.77% in window extraction. In addition, the extracted façade geometric information and element types are transformed into AutoCAD command and script files to create CAD drawings without manual interaction. Experimental results also show that the proposed Scan4Façade method can provide clear and accurate information to assist BIM feature creation in Revit. Future research recommendations are also stated in this paper.
Recommended Citation
Jiang, Yuhan; Han, Sisi; and Bai, Yong, "Scan4Façade: Automated As-Is Façade Modeling of Historic High-Rise Buildings Using Drones and AI" (2022). Civil and Environmental Engineering Faculty Research and Publications. 374.
https://epublications.marquette.edu/civengin_fac/374
Comments
Accepted version. Journal of Architectural Engineering, Vol. 28, No. 4 (December 2022). DOI. © 2022 American Society of Civil Engineers (ASCE). Used with permission.