Photogrammetry

Photogrammetry refers to the highly effective, non-contact process of transforming photos of an asset into a 3D digital model. With the advantages to this process immense, the mining, oil and gas, construction and power generation industries are among the many adopting photogrammetry.

The process of photogrammetry requires overlapping photographs of the physical asset, space or structure to be taken. To be successful the asset is captured from many different angles and locations. It is critical all lines of sight required to be modelled on the asset are captured. These images are then processed into a 3D digital model that replicates this photographed physical asset.

The 3D digital replica, also referred to as a digital twin or reality model, can be used as the digital representation of the as-built physical asset. It can be re-captured periodically to track changes, have external data applied to gain insights, or can be continually manipulated throughout the asset’s lifecycle to reflect any physical changes.

Photogrammetry can be used to capture extremely accurate, realistically textured models of:

• Buildings
• Structures
• Archeological sites
• Landscapes, if the images are taken from the air
• Objects, small or large

Advantages of Photogrammetry

The advantages to using Photogrammetry include:

• The ability to rapidly collect data, which that can be collected with relative ease.
• The ability to create a highly accurate digital twin, which can be manipulated repeatedly, and provide ongoing insights.

Limitations of Photogrammetry

Photogrammetry limitations include:

• Lighting is required to capture the images of the physical asset.
• Visibility constraints, such as rain or fog, can negatively impact image quality for external assets.

Handheld or Ground Based Photogrammetry

Handheld or ground based photogrammetry refers to images captured with handheld cameras or tripod-mounted cameras. It is better suited for capturing smaller objects or areas at very high resolution.

Aerial Photogrammetry

Drones are used to capture aerial photography of large areas, areas that are difficult to access or are simply inaccessible. This drone-captured imagery can be turned in a 3D model or digitally mapped.

Mixed Source Photogrammetry

A combination of handheld or ground based and aerial photogrammetry can capture areas of very high detail within the context of a very large area. Laser scanning data can also supplement the model with additional high accuracy data.

The ALS Approach

ALS continuously looks ahead and regularly invests in the latest technologies available to our industry. With continual advancement and superior customer value a priority, including training and certification of our technicians, ALS is able to continually deliver the most advanced, efficient and effective inspection methods available in the asset care field.