Building and land surveying is a complex and specialised discipline that requires many years of training. Of course, surveying is not new and dates to the earliest days of building projects from the pyramids to Roman temples. Technology has helped to move forward speed and accuracy to a point with the use of total stations, laser scanners and rovers as tools to facilitate the surveyor’s work. Drone technology has rapidly developed so how can they be integrated into surveys?
The use of drones in surveying is a recent development, but it is one that has already shown great promise. Drones offer several advantages over traditional methods, and they are quickly becoming the tool of choice for many surveyors. In this article, we will discuss the benefits of using drones in surveying and how they are changing the industry. We will also look at some of the challenges that come with using drones and how they are being overcome.
Process Advantages and Considerations
There is always a balance to strike in any complex workflow and surveying is no different some considerations are:
- Accuracy of Data That is Required and Precision
- How accurate does the data need to be (often measured in GSD within CM parameters) and what are the consequences if it is not?
- What are the final outputs required such as 3D point clouds/twinning models, orthogram, terrain mapping etc?
- Complexity of the Land – Is the land flat or hilly, treed, or open?
- Size of Land – How big is the area that needs to be surveyed?
- Accessibility – Can you get a vehicle or person to the site to be surveyed?
- Building complexity – Is the building complex or simple in design?
All these considerations will help to shape what technology is used for a specific survey.
- Means of Gathering Relevant Data
- What is the most efficient way to gather the data you need?
- Is there a combination of methods that would work best for the project (ground-based scanners, aerial scans, GPS, etc.)?
- Data Processing – How will the data be processed and delivered?
- What software will be used to process the data?
Answering these questions can help you determine if a drone survey is right for your project.
Efficiency – One of the major advantages of using drones is that they can save time and money. Drones can cover large areas quickly, and they can often do so without the need for ground crews or expensive equipment. In many cases, a drone survey can be completed in a fraction of the time it would take to complete a traditional survey.
Cost Vs Benefits – With any technology, there is a cost associated with its use. Whether purchased or outsourced complex equipment can be a significant overhead for any project. Drones are no different. The cost of drones has come down significantly in recent years, but they still require a significant investment, especially for drones capable of providing high accuracy level data and for larger projects.
In addition to the cost of the drone itself, you will also need to factor in the cost of training, skills, resources, insurance, and software. Overall balancing these factors strongly depends on the desired accuracy and requirement for the outputs that are needed – not all surveying projects require laser point accuracy, whereas for others it is a critical requirement.
Benefits of Using Drones in Surveying
There are many benefits to using drones in surveying. Perhaps the most significant is that they allow surveyors to collect data faster and more accurately than ever before. Drones can cover large areas quickly, and they can reach places that would be difficult or impossible for a human surveyor to get to. This means that surveyors can collect the data they need without having to spend hours walking over rough terrain.
Another benefit of using drones is that they can be equipped with high-quality cameras and sensors. This allows surveyors to capture detailed images and data that would be difficult to obtain with traditional methods they can measure terrain levels, changes, and undulations with a high degree of accuracy. This data can then be used to create orthographic maps and three-dimensional (Orthophoto) models of the area being surveyed.
The use of drones is also much less expensive than traditional surveying methods, such as hiring a helicopter or light aircraft which is particularly necessary in hard-to-reach areas and wide expanses of terrain.
Challenges of Using Drones For Surveying
Despite the many advantages of using drones in surveying, there are also some challenges that need to be considered. One of the biggest challenges is regulations and laws surrounding the use of drones. In many countries, there are strict laws governing where and how drones can be flown. This can make it difficult for surveyors to obtain the permissions they need but not impossible with relevant insights and planning.
Another challenge is that of data security. When collecting data with drones, surveyors need to be sure that the data is secure and will not be lost or stolen. This means that they need to have robust systems in place for storing and backing up data.
Finally, there is the issue of battery life. Drones rely on batteries for power and large areas that need surveying can be a logistical challenge for many standard drones. Whilst battery life is improving and on larger drones like the DJI Matrice 300 carry 2 batteries (giving around 1hr flight time before swapping them out) this needs to be planned carefully to complete tasks. For very large areas the drone company will typically either divide the area up to progress the operation and then ‘stitch’ the segmented projects together afterwards or utilise hybrid drones such as the Wingtra or bespoke VTOL (Vertical Take Off and Landing). These drones act as a ‘wing’ once in flight and therefore require less power to carry out their tasks.
In Summary Drones Offer Another Tool for Surveyors
In many cases, although not all, drones are becoming increasingly helpful and efficient tools to compliment traditional surveying methods. They are not going to replace traditional methods anytime soon but offer another solution for surveyors to consider. When used correctly they can speed up data collection, improve accuracy and save on surveying costs.
