Drones are conquering the construction industry. They help with overview images, detailed shots and thermograms. As a building surveyor and building expert, you can not only leave a lasting impression on your customers, but also transport work processes into a new era. Here you can find out everything you need to know about the possibilities, costs and benefits.
What do building surveyors and experts use drones for?
The most obvious application is overview images from a bird's eye view. All good drones today have an electrically adjustable and stabilised camera that can be moved into the desired position during the flight. Regardless of whether you want to document the facade of a building from the seventh floor upwards or you need a top view of the construction site - the drone helps when your arm gets too short.
Detailed images of damage at great heights
Good zoom cameras cover large parts of daily tasks from the ground. However, sometimes you would like to inspect a detail from close up or from different angles. Here, too, you can utilise the flexible perspective of a drone.
Figure 1: Drone in front of a high-rise facade
In addition to normal visual cameras, professional drones naturally also have a high-resolution thermal imaging camera. Reliably measure temperature differences and discover new possibilities for thermography. Most drones use infrared sensors from well-known manufacturers so that you can simply use your usual analysis software. Simple analysis tools are supplied for all others.
Construction and damage documentation with drones
Drones are generally designed to be very user-friendly. The camera functions are usually controlled via a display integrated into the remote control, which also shows the live image at the same time. The user interface is reminiscent of smartphones and is therefore intuitive.
You simply start the drone at the touch of a button and fly it to the right spot. Focus briefly and trigger the image at the touch of a button - done! The images are saved on a microSD card. After the flight, remove the microSD card from the drone, insert it into your laptop and carry out a brief visual inspection. If everything is in focus, drag the images onto your laptop and you can use them immediately in reports and documents.
Thermography with drones
What works with a visual camera also works with a thermal imaging camera. The market for thermal imaging drones is highly competitive and prices are falling. You can get drones with 640 pixel wide thermal imaging cameras from less than €8,000 - cheaper than some hand-held devices. Thanks to co-operations between drone manufacturers and well-known thermal manufacturers such as FLIR, the devices also deliver what they promise. The typical output formats are R-JPEG or TIFF for seamless integration into well-known analysis software.
Figure 2: Thermal image of a building roof
Special technical features for commercially used drones
You should now have an initial idea of how a drone can support you. In addition to the camera sensor, however, there are a few other factors that you should consider before making a purchase.
Drone remote controls can be divided into those without an inbuilt display and those with an inbuilt display. If you don't have a built-in display, you can save money by simply using your smartphone or tablet as a display. However, performance in cold temperatures is often underestimated: Apple devices and smartphones in particular often react strongly to low temperatures. It is often the case that a flat smartphone battery also means the end of use.
Of course, you don't just use your device to fly drones and must always ensure that you have sufficient battery reserves. The price advantage here is bought by constantly worrying about the battery status of another device. After all, you need to charge the remote control and the flight batteries as well as the smartphone.
With an in-built display, you have no additional effort. The remote controls usually have significantly larger batteries than your smartphone. This largely eliminates the need to worry about power reserves. What's more, you don't have to deal with hanging connection cables - which also makes a better impression on the customer.
For their own protection, manufacturers are increasingly installing pre-programmed no-fly zones in their devices, which not only protect you as a pilot, but also protect the manufacturers themselves from serious mischief with their devices. However, the downside is that you can't take off just anywhere. If you are in a prohibited zone near an airport or government facility, the drone will refuse to take off. The only way out is to unlock the zone by request. Depending on your personality, you may like one or the other option. Decide for yourself.
Figure 3: No-fly zones and warning zones for drones
Safety feature - ADS-B
During a mission, it is often easy to get lost in the picture and forget to monitor the airspace for possible rescue helicopters. This is dangerous! A system called ADS-B can warn you of approaching aircraft by means of an acoustic and visual message. A small feature that is rarely used - but once it has warned you, you won't want to miss it again.
Heatable batteries or heating case
In thermography, the winter period is particularly interesting in order to be able to reliably identify heat transmissions. Of course, you don't want to leave your drone at home at this time of year. Unfortunately, the lithium batteries used in drones do not cope well with cold temperatures. During the take-off phase, the battery is still cold and may already be fully charged - this will affect its service life. Some manufacturers have solved the problem by using self-heating batteries. The batteries warm up before starting and are at operating temperature when you need them.
Legal requirements for commercial drone pilots
If you have decided to buy a drone, you still need to plan a little effort for the legal requirements. For most commercial drone pilots, the large EU drone licence (A2) is their personal ticket to drone operations. You can obtain the large EU drone licence online or offline and should plan for two days of training plus 2-3 afternoons of preparation time.
Of course, the law also stipulates a few other rules that must be observed in everyday life with drones. However, most of the restrictions can be disregarded if you are travelling over private property. The laws primarily regulate safety distances from uninvolved third parties and privacy issues. You will learn everything you need to know about this in ourtraining course for the large EU drone licence.