## Calculate volumes cost-efficiently and precisely

Drones or UAS (Unmanned Aircraft System) are now part of everyday life in many areas. Usually, however, the main purpose (apart from purely recreational use) is to produce normal aerial images, i.e. photos and videos. In the commercial sector, however, the use of drones is already on its way to making processes more cost-efficient that would otherwise require a lot of manpower and time. There are even tasks that only become truly practical and safe to perform with the help of drones. Among these things is volume calculation using photogrammetry, which has long been used for research purposes in archaeology, among other fields. This is a non-contact measurement and evaluation method that enables indirect shape and position determinations from various aerial photographs of a specific object as well as the exact image measurement. What sounds very dry has advantages especially in the volume calculation of objects and goods, which could not be captured otherwise or only with great effort with a similar precision.

### What is the purpose of volume calculation with drones?

For many projects, the recording and calculation of volumes plays a crucial role. Anyone working in the construction industry, for example, knows the challenges associated with calculating the volume of excavation pits, excavated earth, required truck capacities and more. In the same context, operators of gravel pits are hardly in a position to plan their requirements accurately without precise volume recording - not to mention the legally required inventories. In the past, this was done with large uncertainties and estimates that could never be satisfactory in the end. A drone, on the other hand, with the right equipment, is able to use photogrammetry of the aerial photos and subsequent evaluation by software to produce an exact volume calculation at the time the photo was taken. In large projects, even small inaccuracies and fluctuations in the calculations can have an extreme financial and time impact - which is why the use of UAS for surveying purposes has long been commonplace here. It is also particularly interesting that a so-called negative volume calculation is possible - i.e. not only the contents of a container can be recorded exactly, but also the space that is still available there.

### Examples of use for calculating the volume by drone

The gravel pit with its bulk materials or landscaping or the construction industry in general, where large quantities of earth and other volume-based goods have to be moved and transported, immediately light up even laymen. But the drone also performs well in other areas with a volume calculation and/or mass determination. Recycling yards and landfills, for example, can often only design their space management in a very cumbersome way, which amounts to a waste of time and money. Especially in the case of irregularly shaped goods that are thrown into containers by crane or conveyor belt and are also stored in long rows of boxes that are difficult to access, staff often cannot tell at all what the actual state is without looking from above. If at all, the employees often have to undertake dangerous climbing tours for this and invest a lot of time in a rather inaccurate recording. The same applies to construction sites, where operating close to the edge of a quarry can be not only inconvenient but also life-threatening. For all these and other scenarios, the drone is the ideal tool to provide fast and, above all, accurate results for volume calculation.

## This is exactly how the volume calculation via UAS works

Accurate volume determination by drone is not possible with just any device and should always be done by a well-trained professional. In turn, companies can eliminate the need to hire entire survey teams. What can take many hours or even days with a survey team, depending on the size of a project, is often completed within an hour or even faster with a drone. The actual process is as simple as can be. An appropriately equipped drone flies over the object in a specific pattern, which is usually circular or even laid out in grids. The aerial photos are taken by a special camera that creates overlapping images taken at an angle of about 45 degrees. During later analysis, the software assembles these numerous images. But not only that, the metadata of each individual image, which is also registered by the drone during aerial photography, provides the software with information about the exact angle of the current image in relation to the other images.

## Point cloud and 3D model

The results of this evaluation are summarized in a so-called point cloud. These are reference points with the help of which the object differences recorded at different distances and angles are transferred into a 3D model. The subsequent computer evaluation is superior to any classical acquisition in the same time with a very high accuracy. Of course, for this to work, extreme precision is required when flying the drone. Most aerial photographs for volume calculation are therefore created completely automatically. This is made possible by the use of GPS and RTK (Real Time Kinematic), which in combination allow an accuracy of a few centimeters in the acquisition of the data. Once initialized, the coordinates of the reference points can be calculated in real time. This is what makes the drone so efficient and fast in creating aerial images for photogrammetry and volume calculation.

## Conclusion: Drones are a gamechanger in volume calculation

The precise creation of terrain models allows conclusions to be drawn about progress already made or still required on a project via the negative volume calculation. However, professional photogrammetry by drone offers many other possible applications beyond volume calculation. No matter if it is about the recording of bulk materials in quarries and landfills, or the surveying of waste dumps, construction pits or other projects - the drone is a real gamechanger with its modern and efficient volume calculation. In the future, project managers will no longer have to rely on time-consuming surveys or inaccurate estimates to keep their plans up to date.

## How is the volume of an object calculated using drones?

With a drone, the object must first be captured from different perspectives and then processed with special software. These software tools use the geometry and known distances of the captured images to create a 3D model through photogrammetry. This 3D model can then be used to determine and calculate the volume of an object.

## What are the advantages of calculating volumes with a drone?

A volume calculation by drone offers several advantages compared to conventional methods:

• The use of a drone is relatively inexpensive compared to conventional measurement methods such as laser scanners or manual measurements

• By using a drone, the volume of objects that are difficult to access can be calculated without risk

• Volume calculation by drone offers precise results, as a large number of images from different perspectives are used for volume determination

• The use of a drone can provide accurate results in a short time for most applications

## What factors can affect the accuracy of a volume calculation with a drone?

In order to obtain precise results of a volume calculation of an object by drone, high resolution images in high quality from different perspectives are required. The higher the quality of the images, the better and more precise the result. For these reasons, we use a drone with a variety of sensors and a high-resolution camera suitable for industrial applications.

## What safety precautions must be observed when calculating volumes by drone?

When calculating volume with a drone, as with other drone operations, the laws and regulations governing the use of a drone must be followed. Unless special permission is granted, the drone must remain within the pilot's line of sight and must not fly near people or animals. In areas with restricted airspace, special permission from the aviation authority may also be required, and the drone pilot must have all the qualifications to operate a drone.

## What software is needed for volume calculation by drone?

To create a volume calculation by drone, there are several software tools that use photogrammetry to create a 3D model from images captured by a drone. Since the software requires high quality images in large numbers to provide accurate results, very high computing power is required.

## Where is volume calculation by drone used?

A volume calculation by drone can be used in various application areas where the volume of an object needs to be calculated. For example, for buildings, structures, terrain, hills or holes and other geometric shapes. For landfills, before-and-after comparisons can be used to accurately determine the amount of fill. Volume calculation by drone can be used in construction, mining, agriculture, forestry, and many other industries to provide up-to-date information without manual surveying. This approach helps save time and money.