Across industries, the use of Digital Twin is increasing. Often defined as ‘virtual copies of physical assets’, Digital Twin delivers great value by providing a holistic view of the asset within its operating context. While this technology can help organisations to better manage their assets and reduce costs, integrating this technology into the business processes comes with some challenges.
Understanding the pros and cons of various Digital Twin technologies ahead of time can help companies make smart decisions about how to implement this promising technology.
Our philosophy is simple; our customers understand and know their requirements for site inspection and maintenance better than anyone. That’s why we have built our Digital Twin software based around specific customer requirements and not theoretical models.
Focussed on the inspection and maintenance parts of the asset lifecycle, our experience in the Oil and Gas sector and delivery of 3D CAD models led us to the adoption of our Digital Twin strategy. Rather than using a one-size-fits-all approach, to meet the needs of businesses in the Telecommunications, Transmission & Distribution and Oil & Gas industries, Inspection² software supports 8 different types of Digital Twin.
Let’s take a closer look at each of these, we will provide some guidance on their use, benefits and drawbacks
1. 3D Photogrammetry
3D Photogrammetry models (which are generated from standard 2D imagery) use reference points within an image and relate the relative position of those points across multiple images to form a 3D model.
To get the best results this technique requires the use of drones for data capture, as they provide angles and coverage not only the vertical structure but also around the top of towers, both critical to accurate modelling.
Photogrammetry models can be generated with or without GPS data although it is better with GPS as it improves both generation and usability.
Pros & Cons
Photogrammetry models are good for visualisation because they fully represent the asset in 3D as it is on that day and allows users to compare over time. Useful for survey and land assessment, they work especially well on flat structures such as buildings and contain useful geo-positioning information and a good selection of measurement tools.
However, there are some key considerations to be aware of:
- Structure type: does not work well for lattice structures.
- Inspection and inventory analysis are basic: does not provide detailed component or anomaly analysis. Users will also need to revert to 2D images in some form.
- Processing time: There is a processing time before you see the 3D photogrammetry model.
Ultimately, whilst improvements can be made manually to the model on the desktop it remains a visualisation tool and so does not provide automation for scale.
2. 3D CAD
3D CAD models are produced using common software tools, including AutoCAD, Blender and Sketch Up amongst others. Created within a virtual 3D space, the models have three points of reference and are built via a series of polygons. The higher the polygon count the larger the size of the model. There is a wide range of file formats for 3D models, the most common being .OBJ and .DAE.
Pros & Cons
One of the major benefits is flexibility – they are easy to integrate across other software types and provide a full range of measurement tools for analysis and design. You can link additional elements, such as marking up anomalies or points of interest. As such, they represent the ‘As Built’ model rather than the ‘As Is’, so manual updates are required to maintain accuracy to the real world. While excellent for certain engineering tasks, the fact they are not photorealistic means they are not suited to all applications.
Overall, the quality and accuracy of the models can be extremely high but is dependent on the experience and quality of the 3D CAD Modeller, and larger models also require good bandwidth to run properly.
As the 3D CAD model is a single object, the model is not addressable at the component level such as an antenna or cable.
3. 3D Lidar
Lidar is the most advanced Digital Twin technology that we use. At a very basic level, the technology uses a laser to scan an object. When the laser strikes the object, it measures the distance. Using millions of these points, a 3D point cloud is then built up. With the right type of lidar scanner, the 3D point cloud can then be rendered. There are three main types of lidar files: .LAS, .LAZ, and .LGS.
It is important to make the distinction between Lidar that is used for SLAM type applications (which enable the automatic navigation of cars and drones) and the lidar that is required for asset inspection. The leader in this latter field is Leica.
The next generation of lidar is likely to be ‘flash lidar’, but that remains several years away yet.
Pros & Cons
Laser scanning is considered state of the art at a commercially viable level. It is highly accurate when compared to some of the other methods and there is a full range of measurement software tools available. It enables full virtual walk-around of a site, giving engineers a complete ‘as is’ picture of a tower in the built environment with great accuracy
However, it is expensive, data-heavy and deep integration and manipulation of the point cloud is not as advanced as other Digital Twin methods.
4. 3D World Environment
3D Worlds effectively deliver full digitisation of the earth in images. They are created primarily by using satellite imagery, with many supported by streetmaps.com. They provide a basic 3D real world-based environment which acts as a base platform but is not configurable enough to form a full solution on its own.
As a result, companies which typically use instant functionality straight out of the box have been slow to take up the technology.
Pros & Cons
Being a specialist software company that is used to dealing with 3D and Geospatial software, we absolutely recognise the benefits these environments can bring to our customers when we work in partnership to create a full solution. Some of the sector-specific functions which we have developed on top of these base environments allow you to:
- Geo-position generic or specific 3D CAD models into that full 3D world.
- Geo-position handheld and drone-captured imagery around your asset.
- Automatically geo-positioned asset anomalies in the 3D world.
- Mark up sites and site project locations in the 3D world.
- Draw up a line of sight between cell towers to form a visible network in the 3D world.
- Colour code assets by multiple statues and categories in the 3D world.
5. 3rd Party BIM
Technically BIM is a methodology, primarily used in medium to large construction projects. Based around a central 3D CAD model that is component aware, are a defined set of properties and characteristics.
This is then delivered to the multiple different user groups involved in the construction project through a single central piece of software with the ability to relate components, properties, characteristics and relationships between each, in an intelligent way.
Inspection² software is not a BIM system since we are focussed on a different part of the asset lifecycle and provide a different service, focussed on achieving maximum automation once built. As such our strategy will always to be to integrate with and work alongside BIM software.
BIM software is based around a 3D ‘component-driven’ CAD model. Those components can be defined with different properties and characteristics and this is then supported by a dynamic inventory of the asset
As the asset inventory is linked to the model, if you change one characteristic it is reflected across the inventory. A well-defined BIM model enables you to feed that information into ‘simulation software’.
Pros & Cons
- A BIM model is an ‘As Built’ model. You still need another process to capture the ‘As Is’ status and bring the model up to date.
- BIM models do not handle anomalies, defects, and issues with assets, they are an ‘As Built’ model.
- BIM methodology and software comes from the medium to large scale building and construction industry. Cell tower structures or rooftop installations have little need for this level of software tooling and approach.
- A full retrospective BIM modelling of 10,000 cell towers would be extremely time-consuming. Particularly given the relatively simple nature of cell towers and the use of 3rd Parties in design and construction.
- A lot of the BIM software is desktop-based and can be clunky to share and integrate with. That is also true for cross-asset reporting.
6. 360° Imagery
Strictly speaking, these are not Digital Twins, but they can be useful for anomaly assessment. The 360-degree pictures, capture around the asset are not only photorealistic but also gives you the full context of the asset from one viewpoint. On Inspection² platform, telecom engineer can use the Spin Model, an inward-looking 360°, created by linking 2D images of the tower, in a sequence. When the sequence is played is gives the effect of rotating 360° around the tower, at various headframe levels and top-to-bottom cable run.
Pros & Cons
They provide an up-to-date digital representation and when used with additional sector-specific software, their use can be enhanced. For example, when combined with compass bearing and directional satellite mapping it becomes a very useful tool for cell tower inspection and analysis.
However, they are static and only capable of showing a 360° perspective around a single defined point.
7. Fully integrated 360 Models
This is a big step up on 360° imagery. Multiple 360-degree pictures are taken, usually using specialist cameras. These multiple 360° images along with the reference and metadata, are then stitched together into an integrated model of the asset.
Pros & Cons
These models deliver high definition photo-realistic imagery and represent exactly how the asset or site is today. You have reasonable measurement capabilities with them and it is quick to generate the 360° models.
While it is not true 3D, if the capture is done well there is a real sense that you are moving through a 3D representation of your cell site, so this technology works well for presenting to customers. Most of these services are on-line and relatively easy to integrate with.
It does have limitations, take tower capture for instance:
- While further drone and camera integration might be able to solve the issues, this is not something we have yet seen done effectively.
- The software is clear, but what you are doing is zooming into and out of a flat 2D image as opposed to a true 3D image.
- Because of the 2D nature of the 360 models, you will be limited in what you can see and what you can measure.
- Annotation is done on a flat plane and not on an actual component.
While not at lidar prices the cameras are still relatively expensive, and you need to know how to use them to get the best out of them.
8. 2D schematic
This may sound outmoded, but we have several customers that have legacy assets documented in this way. As a result, we maintain the importance of supporting an asset-only approach to enable the use of traditional schematics with 2D imagery
Pros & Cons
2D Schematics are well understood and established and can record a full asset inventory which you can keep up to date using the captured and linked 2D imagery. Integration into other 2D CAD software models such as AutoCAD is important, as this enables you to support existing documentation.
As with all the other Digital Twins you can record a full asset inventory which you can keep up to date using the captured and linked 2D imagery.
However, it doesn’t give a 3D or virtual walk-around environment and the geo-position functions and feature are limited.
With today’s technology and software, most people will be looking for 3D representation and more dynamic tools that are available.
Selecting the right Digital Twin tools to meet your requirements
We have been focusing on what drive customer economics and business outcomes. In the current environment where there’s fewer people available and more remote work, it is critical to have the right tool in place to help operational processes to be reliable, safe, and scalable.
Despite the huge potential of Digital Twin, many companies might fail to maximise the value of the technology as they tend to focus on what the technology can do, rather than what could generate the most value for the business. Having deep industry expertise with an asset-centric view of the Digital Twin, we can help find the right solution for your business.
A successful Digital Twin strategy is about a seamless and integrated ecosystem; not a standalone product. Talk to our team to know more.