The Benefits of 3D Modelling

 

From point cloud to 3D model and BIM

Point cloud technology has been fundamental to the development of 3D modeling. A point defines an object in terms of its shape and position in space (X, Y, Z coordinates) but more can be added to this such as color, texture and pattern.

By collecting data from aerial surveys and photogrammetry and storing these as points in a cloud, it is then possible to take the step from point cloud to 3D model using specially developed software such as that produced by PointFuse.

With the PointFuse software, 3D models are intelligently optimized so that only the information you need at that time is shown, making the process extremely fast. This facilitates better collaboration between designers and through this, it is possible to quickly see where clashes occur and where changes need to be made.

When used with Building Information Modeling (BIM), point cloud data is enhanced by providing further information on each building component to deliver a complete working model using point cloud scan to BIM software.

BIM can then be used to create schedules and 2D drawings for a multitude of purposes, such as ordering replacement parts, creating room data sheets, developing maintenance manuals and space management. Point cloud scan to BIM software is also part of the package provided by PointFuse.

 

How are 3D models used?

Once a model has been created it can be used at all stages of the project to suit the needs at the time.

Concept design stage

Many believe that this is the most important stage of a project because it is at this point that ideas are developed, options are considered, budgets are set and the decision to proceed to the next stage is made. To provide the best possible advice on which to base that decision, the data used to create the model must be as accurate and comprehensive as it possibly can be at that point in time.

 

Production information stage

A three-dimensional model is fine for designing and gaining approval, but when it comes to producing information that can be used to produce the building or structure on site, it is necessary to convert that data into a two-dimensional format.

Plans, sections and elevations are created from the model itself. They are not a separate entity. Hard copies of these can be created by printing off drawings for use as contract documents (a record of what formed the offer and what was accepted), planning consent and building permits. They will be issued to the site for use in the construction process.

However, as the design develops, it is through the model, not the media of the drawings, therefore the model is always the focal point of the design. Clash detection is a huge advantage of using the model for design during this stage to avoid any issues later once on site.

Three-dimensional models have been around a long time, but before the introduction of the point cloud, they could not contain all the detail necessary to build from. Details were drawn as separate entities, usually two-dimensionally making them prone to error and difficult to synchronize with other as-built information.

Using point cloud to 3D model software, it is possible to go into the finest detail, to see just how the building can be constructed, and to validate this against the detail as it is built.

 

Construction

As work progresses on site the building should be scanned at various stages to ensure that the model is always up-to-date.

Sub-contractor designed elements will be incorporated into the model as well during this stage, and further checks on clash detection can be made. This is essential in the case of heating, cooling, plumbing and ventilation services which must be designed with structural elements in mind.

 

Completion

Once the building is complete, the model stands as a representation of what was built. During the previous stages, the model was updated as changes were made, so what remains is an as-built BIM. As such, it can be used for maintenance purposes, to plan spatial changes, as a guide for further development—such as an expansion project—and eventually to show how the building can be demolished or dismantled in complete safety.

Summary

For the moment at least, there will always be a need for a 2D representation of a building or structure to convey to the construction team the methods and sequences in which it will be built. Holographic models on site are still some way off, so in the meantime, scaled-down plans, sections and elevations will be used. The ‘blueprints’ of old will still be needed in construction.

Using old technology, facilities managers have to rely on marked up sets of drawings, which are added to as the building is modified, resulting in inaccurate information, and time-consuming remeasuring and validation on site.

However, through the use of point cloud technology, building owners can take full advantage of the speed and accuracy of the 3D model and to fully utilize the potential of BIM. The ‘as-built’ drawings and schedules can now take the form of digital information. This has the added advantage of being easily and quickly updated as the building changes over time. When partitions are moved or services upgraded, the model can be updated immediately, down to the finest detail.