## 3 Building Asset Facility Management
### iMMS Platforms for Asset Management Applications: General Principles  
The software-based systems discussed in Section 3.1, particularly those using tablets to upload maps of visited areas, have evident disadvantages. Building plans must be available, object recognition must be performed by the operator in the field without a photographic record of the current condition, and 3D measurements cannot be taken. Additionally, 3D measurements of the entire or partial environments traversed cannot be extracted. The introduction of mobile mapping devices integrated with high-quality cameras has expanded the potential uses of iMMS systems. Initially developed as self-locating devices and later used for rapid surveys in indoor environments, iMMS instruments can now efficiently record assets in various contexts, thus supporting geospatial applications (Figures 4 and 5).  
Figure 4: Example of a virtual tour of a survey carried out by iMMS (University of Brescia Campus). The image shows what is visualized by the software and represents a virtual tour through the mapped site. On the left-hand side, the point cloud projection onto the horizontal plane is displayed. The yellow line indicates the trajectory followed by the surveyor, and the blue dots represent the positions where the on-demand spherical images were taken.  
Moreover, alongside the three-dimensional survey of the sites, the imaging features enable the recognition of assets within buildings and allow for three-dimensional measurements. In addition, if not yet available, it is possible to obtain floor plans or elevations of buildings.  
SLAM surveying allows, at the same time, to be employed for classical surveying activities, while photographic acquisitions can be used for the recognition and positioning of assets within buildings, as well as for evidentiary documentation of the actual state of a building. By positioning, in this case, we do not mean just the spatial coordinates of where such an asset is located, but rather the knowledge of the environment in which the assets are situated. For example, knowing the location of a fire extinguisher placed inside a building means also being able to indicate in which room, in which building, and on what floor of that building the fire extinguisher is located. This example illustrates that the way to carry out a classic survey with iMMS instrumentation aimed at topographic mapping of a building is radically different from the process for an asset survey activity. Different objectives are pursued with different methods and procedures, which will be appropriately described in the following paragraphs. Surveying with dynamic instrumentation, therefore, allows for the production of different deliverables.  
The deliverables that can be obtained from iMMS instruments are analyzed in the following paragraphs, where the challenges and methods for extracting these products are described, along with general operational advice based on activities focused on asset management rather than accurate 3D topographic surveying. Depending on the deliverables to be extracted from a survey using dynamic instrumentation, the choice of iMMS instrumentation to be used in surveying activities is also determined. The following paragraphs aim to provide guidelines for selecting mobile surveying systems based on the deliverables intended for asset management activities.