fast indoor mapping to feed an indoor db for building and facility management

Abstract. Facility Management activities require to collect and organize a large amount of information about a building as, for example, geometry, MEP structures, lighting and antifire devices, typologies of furniture, paving characteristics, structures and more. Nowadays the data acquisition procedures for indoor environments are usually still carried on with old style approach, where surveyors have to manually map and acquire the data, walking along the sites with a poor level of digitalization The success story presented in the paper describes how using an Indoor Mobile Mapping approach (Zlot et al., 2014), it is possible to satisfy the need to acquire plant views of a large parts of buildings and, simultaneously, to record a 3D+Full resolution RGB images. Thanks to this fast acquisition it is later possible to feed a 2D/3D database, identifying the main objects needed to support a facility management process. The iMMS that has been used is based on SLAM approach, that allows the user to map and survey large sites also indoor, that means without the presence of GNSS signal and without the use of accurate and expense IMU devices. The data acquired in the field has been process with standard/commercial software that is usually used to create DB for outdoor mobile mapping.</p

Recent evolution of the Punta San Matteo serac (Ortles-Cevedale Group, Italian Alps)

This paper summarizes the main results of surveys carried out on the Punta San Matteo serac (Ortles-Cevedale Group, Italy). The monitoring campaigns mainly consisted in surveying the serac with a Total Station (over the period from July 2005 to November 2005) and with a laser scanner. The displacements of the unstable ice mass (about 12 m) and its geometry and volume (about 560,000 m') have been calculated. In addition several photographs collected during the field campaigns made it possible to describe the evolution of this unstable ice mass and recorded its partial collapse and gradual breaking into tiny parts. The air temperature trend was also evaluated; the serac displacements resulted not strongly correlated with temperature evolution and the main falling events occurred in the autumn and not in summer when air temperature reached the highest peaks

Preliminary survey of historic buildings with wearable mobile mapping systems and uav photogrammetry

In cultural heritage, three-dimensional documentation of historic buildings is fundamental for conservation and valorisation projects. In recent years, the consolidated tools and methods: Terrestrial Laser Scanning (TLS) and close-range photogrammetry, have been joined by portable Mobile Mapping Systems (MMSs), which can offer significant advantages in terms of speed of survey operations at the price of reduced accuracy. The reduction of survey times and, therefore, costs makes the application of MMS techniques ideal for the preliminary stages of analysis of historical artifacts, when a rapid survey is indispensable for estimating the costs of conservation interventions. In this paper, we present a methodology for the expeditious survey of historic buildings and the surrounding urban fabric that is based on the use of an MMS and an Unmanned Aerial Vehicle (UAV). The MMS is the Gexcel Heron MS Twin color. It was used to survey two architecture of interest and the urban context surrounding them from the ground level. The UAV is the DJI Mini 2, used to integrate the terrestrial survey by acquiring the buildings' roofs. The case study presented in the paper is the survey of San Clemente and San Zeno al Foro churches, two historic churches in the city centre of Brescia (Italy). The result are a complete point cloud of the two buildings and a metric virtual tour of all spaces. These results were made available to the architects through the Cintoo web platform to plan future activities

BUILT-IN LENS CORRECTION PROFILES IN LOW-COST CAMERAS: AN ISSUE FOR PHOTOGRAMMETRIC APPLICATIONS?

Photogrammetric applications nowadays envisage the use of more and more low-cost cameras such as those equipped on commercial UAV platforms. Typically, these low-grade cameras suffer from extreme radial distortion and strong vignetting among other defects. This, initiated a trend among the low-cost cameras’ manufacturers to try to hide the camera defects by applying software pre-corrections to the images. These Built-In Correction Profiles gets applied to both the JPG files, directly in-camera, and usually to the raw files as well, through the opcode functions of the DNG standard. In this paper we rise this issue that is still under-reported in the literature and further assess the accuracy implication of applying or discarding the Built-In Correction Profile in the scenario of UAV mapping. We tested the commercial UAV DJI Phantom 4 Pro v2 in a calibration environment and a field test to compare the performance of pre-corrected versus uncorrected images. In our tests, processing the original uncorrected images led to improved IO calibration and reduced bowing effect in the field test

SURVEY OF HISTORICAL GARDENS: MULTI-CAMERA PHOTOGRAMMETRY VS MOBILE LASER SCANNING

This paper presents an investigation into the characterization of historical gardens by comparing two 3D survey methodologies. In this context, approaches employing terrestrial laser scanning are considered the most accurate, while Mobile Mapping Systems (MMSs) are considered promising due to their extreme productivity. Less common is the use of close-range photogrammetry. This paper compares two approaches based on the use of a wearable MMS and the use of an in-house built photogrammetric multi-camera prototype. The comparison aims to assess the applicability of the two techniques in this field, evaluating their advantages and disadvantages in surveying a historical garden and extracting information for tree inventory, such as the DBH (Diameter at Breast Height) and canopy footprint. We compared the practicality of surveying and processing operations; and the quality and characteristics of the point clouds obtained. Both systems produced a dense representation of the terrain. The multi-camera survey resulted to be more defined due to the lower noise of the point cloud but incomplete in the definition of tree canopies. DBH of tree trunks can be extracted with both systems, except for thinner and finer diameter trunks detected by the MMS approach but not always by the multi-camera. The MMS approach proved more effective thanks to a shorter survey time required to cover an equal area and the fact that the MMS survey alone is sufficient for the geometric description of trees. In contrast, the multi-camera approach cannot avoid integration with an aerial survey for canopy reconstructio

Deep panoramic depth prediction and completion for indoor scenes

We introduce a novel end-to-end deep-learning solution for rapidly estimating a dense spherical depth map of an indoor environment. Our input is a single equirectangular image registered with a sparse depth map, as provided by a variety of common capture setups. Depth is inferred by an efficient and lightweight single-branch network, which employs a dynamic gating system to process together dense visual data and sparse geometric data. We exploit the characteristics of typical man-made environments to efficiently compress multi-resolution features and find short- and long-range relations among scene parts. Furthermore, we introduce a new augmentation strategy to make the model robust to different types of sparsity, including those generated by various structured light sensors and LiDAR setups. The experimental results demonstrate that our method provides interactive performance and outperforms state-of-the-art solutions in computational efficiency, adaptivity to variable depth sparsity patterns, and prediction accuracy for challenging indoor data, even when trained solely on synthetic data without any fine tuning. (Figure presented.

SCAN-TO-BIM EFFICIENT APPROACH TO EXTRACT BIM MODELS FROM HIGH PRODUCTIVE INDOOR MOBILE MAPPING SURVEY

Building Information Modeling represents one of the most interesting developments in construction fields in the last 20 years. BIM process supports the creation of intelligent data that can be used throughout the life cycle of a construction project. Where a project involves a pre-existing structure, reality capture can provide the most critical information. The purpose of this paper is to describe an efficient approach to extract 3D models using high productive indoor Mobile Mapping Systems (iMMS) and an optimized scan-to-BIM workflow. The scan-to-BIM procedure allows reconstructing several elements within a digital environment preserving the features and reusing them in the development of the BIM project. The elaboration of the raw data acquired from the iMMS starts with the software HERON® Desktop where a SLAM algorithm runs and a 3D point cloud model is produced. The model is translated in the Gexcel Reconstructor® point cloud post processing software where a number of deliverables as orthophotos, blueprints and a filtered and optimized point cloud are obtained. In the proposed processing workflow, the data are introduced to Autodesk ReCap®, where the model can be edited and the final texturized point cloud model extracted. The identification and modeling of the 3D objects that compose the BIM model is realized in ClearEdge3D EdgeWiseTM and optimized in Autodesk Revit®. The data elaboration workflow implemented shows how an optimized data processing workflow allows making the scan-to-BIM procedure automatic and economically sustainable

SURVEY OF HISTORICAL GARDENS: MULTI-CAMERA PHOTOGRAMMETRY VS MOBILE LASER SCANNING

This paper presents an investigation into the characterization of historical gardens by comparing two 3D survey methodologies. In this context, approaches employing terrestrial laser scanning are considered the most accurate, while Mobile Mapping Systems (MMSs) are considered promising due to their extreme productivity. Less common is the use of close-range photogrammetry. This paper compares two approaches based on the use of a wearable MMS and the use of an in-house built photogrammetric multi-camera prototype. The comparison aims to assess the applicability of the two techniques in this field, evaluating their advantages and disadvantages in surveying a historical garden and extracting information for tree inventory, such as the DBH (Diameter at Breast Height) and canopy footprint. We compared the practicality of surveying and processing operations; and the quality and characteristics of the point clouds obtained. Both systems produced a dense representation of the terrain. The multi-camera survey resulted to be more defined due to the lower noise of the point cloud but incomplete in the definition of tree canopies. DBH of tree trunks can be extracted with both systems, except for thinner and finer diameter trunks detected by the MMS approach but not always by the multi-camera. The MMS approach proved more effective thanks to a shorter survey time required to cover an equal area and the fact that the MMS survey alone is sufficient for the geometric description of trees. In contrast, the multi-camera approach cannot avoid integration with an aerial survey for canopy reconstruction

TARGETLESS REGISTRATION METHODS BETWEEN UAV LIDAR AND WEARABLE MMS POINT CLOUDS

Fixed-wing Unmanned Aerial Vehicles (UAV) and wearable or portable Mobile Mapping Systems (MMS) are two widely used platforms for point cloud acquisition with Light Detection And Ranging (LiDAR) sensors. The two platforms acquire from distant viewpoints and produce complementary point clouds, one describing predominantly horizontal surfaces and the other primarily vertical. Thus, the registration of the two data is not straightforward. This paper presents a test of targetless registration between a UAV LiDAR point cloud and terrestrial MMS surveys. The case study is a vegetated hilly landscape characterized by the presence of a structure of interest; the UAV acquisition allows the entire area to be acquired from above, while the terrestrial MMS acquisitions will enable the construction of interest to be detailed. The paper describes the survey phase with both techniques. It focuses on processing and registration strategies to fuse the two data together. Our approach is based on the ICP (Iterative Closest Point) method by exploiting the data processing algorithms available in the Heron Desktop post-processing software for handling data acquired with the Heron Backpack MMS instrument. Two co-registration methods are compared. Both ways use the UAV point cloud as a reference and derive the registration of the terrestrial MMS data by finding ICP matches between the ground acquisition and the reference cloud exploiting only a few areas of overlap. The two methods are detailed in the paper, and both allow us to complete the co-registration task

Paediatric non-alcoholic fatty liver disease: impact on patients and mothers' quality of life

Background: Non-alcoholic fatty liver disease (NAFLD) is one of the causes of fatty liver in adults and is currently the primary form of chronic liver disease in children and adolescents. However, the psychological outcome (i.e. the behavioural problems that can in turn be related to psychiatric conditions, like anxiety and mood disorders, or lower quality of life) in children and adolescents suffering of NAFLD has not been extensively explored in the literature. Objectives: The present study aims at evaluating the emotional and behavioural profile in children suffering from NAFLD and the quality of life in their mothers. Patients and Methods: A total of 57 children (18 females/39 males) with NAFLD were compared to 39 age-matched control children (25 females/14 males). All participants were submitted to the following psychological tools to assess behavior, mood, and anxiety: the Multidimensional Anxiety Scale for Children (MASC), the Child Behavior Checklist (CBCL), and the Children's Depression Inventory (CDI). Moreover, the mothers of 40 NAFLD and 39 control children completed the World Health Organization Quality of Life-BREF (WHOQOL-BREF) questionnaire. Results: NAFLD children scored significantly higher as compared to control children in MASC (P = 0.001) and CDI total (P &lt; 0.001) scales. The CBCL also revealed significantly higher scores for NAFLD children in total problems (P = 0.046), internalizing symptoms (P = 0.000) and somatic complaints (P &lt; 0.001). The WHOQOL-BREF revealed significantly lower scores for the mothers of NAFLD children in the overall perception of the quality of life (P &lt; 0.001), and in the "relationships" domain (P = 0.023). Conclusions: Increased emotional and behavioural problems were detected in children with NAFLD as compared to healthy control children, together with an overall decrease in their mothers' quality of life. These results support the idea that these patients may benefit from a psychological intervention, ideally involving both children and parents, whose quality of life is likely negatively affected by this disease