SBL has been making steady and sustained progress in developing its BIM services portfolio over the last couple of years. Our last blog post on our BIM services was nearly 4 months back (October 2016) when we showcased our capabilities to model railway assets using point cloud data acquired from mobile and terrestrial scanners. Since then our BIM and LiDAR teams have been quite busy in working on a variety of BIM and LiDAR projects and pilot samples. One such interesting work was from the UK where our BIM team was given a 3D point cloud data acquired using ZEB-REVO handheld scanner. The ZEB-REVO handheld scanner was used to acquire the internal details of a warehouse at nearly 37000 ppm². The acquired point cloud data had only elevation values and no RGB values. No reference photographs were provided.
Figure 1 – Input point cloud data thematically represented by elevation data
The lack of RGB values in the input point cloud data and the absence of reference photographs poses a challenge to anyone desiring to model the individual features present in the data. SBL overcame this challenge due to the availability of highly skilled and experienced modellers who were fully conversant of the features expected to be found in a warehouse. The internal features of the warehouse was modelled with high accuracy using Aecosim Building designer software from Bentley. The 3D model of the warehouse was rendered to create realistic looking and highly accurate photo images of the warehouse. Multiple views of the rendered model are included below.
Figure 2- Rendered output of the warehouse (view 1)
This 3D models was used by the architects of the warehouse to notice design issues or weaknesses in the structural integrity of the site and to predict failures such that preventive maintenance can be done to minimize damage. Architects and engineers can also manipulate 3D models in a way they often can’t with 2D CAD drawings. Professionals are able to test what-if scenarios with their designs in 3D, helping to validate their plans and identify any problems with design quality. In addition, these types of models can also give architects and engineers an accurate picture of how they can change their designs if they need to. Because of the accuracy and flexibility of 3D models, architects and engineers are able to spend less time on the design stage of their projects and more time on the actual completion of each task. Professionals are able to identify any issues ahead of time by using 3D modeling, saving them from having to rework schedules and increase budgets.
With this project completed successfully, the SBL BIM – LiDAR team once more proves that it has the technical acumen and skills to overcome the toughest of challenges in completing projects in their domain of expertise.
With the global drive towards Building Information Modelling (BIM) compliance gathering pace, we have seen an increased requirement for highly accurate and detailed geospatial data within utilities and engineering projects. This has resulted in a corresponding increase in the application of LIDAR technology within these sectors.
In particular, railways have a wide range of complex and critical assets that extend across the rail network. LiDAR survey point cloud data and feature extraction has become an accurate and effective means of modelling, sharing, managing and storing large asset information databases of this sort.
The primary benefit of LIDAR technology lies in its ability to capture assets in 3D. For rail networks, train mounted LIDAR equipment is on the increase because it allows accurate, dense point clouds to be acquired along with the RGB images from the in-cabin video. Having worked on a number of such high-profile projects, SBL has built up a large team of LIDAR modellers and analysts who can process and extract the full range of railway features and assets.
Railway assets include electrical network and equipment, telecommunication network and equipment, tracks and related features, signal systems and station assets. The advantage of deriving 3 dimensional data from LIDAR point clouds is that it will be accurate to a millimetre level. All the peripheral equipment can be modelled in a 3D environment as well. Along the tunnel sections of the network LiDAR is the only technology that can provide comprehensive, highly accurate information on assets.
Fig 2 station and its component assets as captured from LIDAR point clouds
Mapping to high detail and then rendering in various model platforms is the key to usage of LIDAR based capturing of railway assets. All features within the corridor width of the tracks can be captured to the same very high detail. Stations have innumerable assets components but all these components can be captured effectively using LIDAR point clouds. The creation of a real world situation using 3D models has attracted the attention and approval of many of SBL’s stakeholders and partners. Our LIDAR analysts have achieved these impressive results through 3D wire frame and surface modelling. These models were created and delivered in global GIS formats such as .dgn or .dwg or gml.
This kind of LIDAR technology based railway mapping will benefit different disciplines in different ways. This database will act a pre indicator for drivers and is of great help in their training. For construction engineers it is a monitoring mechanism. For design engineers it the only information provide kinematics of the entire system. For maintenance and operation teams it is a database where they can pinpoint hot spots where repairs are required allowing ground staff to be sent directly to those locations. Using this database a virtual railway stations and tracks can be created for various applications. Overall asset and facilities management will be greatly improved with such a 3-dimensional database.