The Drone: a multipurpose inspector
The proximity inspection is a type of activity that often requires economic investments of a certain size in order to be carried out. Scaffolding, baskets, mobile systems for ad hoc investigations, in addition to requiring investments, require time to be prepared, and often have physical limits that do not allow the inspection investigation to be carried out as it should be.
Here, therefore, albeit with its limits, the drone comes into play which, hovering in the air, can reach areas subject to inspections not otherwise accessible. With its video camera and with the possibility of recording videos in 4K it can contribute to the cause and save time and money.
It is good to highlight that drone inspections can be part of both a routine (maintenance) and scheduled activities ad hoc to identify a specific problem.
Drone inspections – The role of the pilot
Obviously there is no sudden inspectors with drone. First of all because the drone pilot must be in possession of the qualification to fly for critical operations (it is not enough to have the ENAC online license), moreover the aerial data collected by the drone must be analyzed and interpreted by a competent certified technician, in relation to the type of inspection being carried out.
So if we are talking about a visual inspection on a viaduct, the analysis of the data collected must be carried out by a certified level II visual inspector of bridges and infrastructures.
And again if the purpose is to perform a thermographic analysis of a facade of a building to establish, for example, the tightness of the thermal coat or check the possibility of detachments, this must be carried out by a certified level II thermographic operator.
It therefore clearly emerges that the pilot has the task of inspecting the aerial data in a detailed and precise way (and this perhaps on the basis of a plan made with who will analyze the data). If the pilot is also a certified inspector in the specific field of investigation he is carrying out with the drone that is better.
Features of the inspection drone
The conduct of an inspection, the purpose of which is to capture high resolution images, requires (at least on paper), a drone with certain specs and performances such as:
- Flight stability – for smooth and accurate data acquisition,
- small size – to be able to “enter” confined areas,
- adequate wind resistance – to operate at high altitude and in areas subject to wind and gusts,
- video camera with UHD or 4K resolution – for capturing high resolution images,
- optical-digital zoom – for capturing distant details,
- adequate flight time – to carry out the mission or a large part of it,
- controller connectable to tablet – for a better view of the telemetry and what the drone “sees”,
- sufficiently “rugged” – for carrying out operations in disparate environments.
It should be noted that: flight stability, small size, adequate wind resistance, video camera with UHD or 4K resolution, optical-digital zoom, controller connectable to tablet, “rugged” nature are essential and essential requirements.
Regarding the flight time, however, this limitation can be remedied by organizing multiple missions, provided that you have more battery packs.
In the case of thermographic inspections, the drone must also be equipped with a thermal imaging camera in the infrared spectrum, as well as with a camera in the visible. For drones assigned to this activity it is always good to choose solutions with a native thermal imager or already part of the machine without having to create solutions that can affect both the flight time and the results of the inspection.
300 grs drones for inspections
Given the widespread diffusion, it is worth mentioning the use of drones weighing less than or equal to 300 grams, as tools for urban inspections.
These drones, at least until the entry into force of the EASA regulation of 1st July 2020 (if confirmed!), for the different categories such as “Open” and “Specific“, can in fact fly in urban areas without a certificate for critical operations (art. 12 paragraph 5 of the ENAC regulation).
Given that these drones hardly meet the requirements for an inspection drone, for this type, all operations are non-critical in all scenarios.
These drones that fall into the harmless drone category, as defined by ENAC, can operate in urban areas (e.g. roof and roof inspections, building facade inspections, etc.), but must meet the following requirements:
- be equipped with propellers,
- fly at a maximum speed of 60 Km / h,
- be registered with d-flight,
- have insurance for professional activities,
- never fly on crowds of people.
Beyond the requirements, however, it remains contradictory that if you use a drone to carry out a work activity you need a certificate for critical operations. So the question remains open, regardless of whether these drones are not currently born for inspections.
In all fairness, a generic 300 grs drone cannot perform the inspection activity, unless it limits us to the analysis of the roof of the aunt’s house.
The importance of zooming on inspection drones
Zooming on drone cameras is an essential tool to first overcome the limitations imposed by the ENAC regulation (Italy), and then to obtain detailed images where required.
In the case of urban inspections, in fact the zoom can in some cases allow the pilot to remain in the context of a non-critical operation, by-passing beyond the certificate (which in any case is better to have for important and delicate operations such as inspections ), also the plethora of permits that must be asked to fly in urban areas.
On the other hand, it should be remembered that the purchase of a zoom video camera payload is not painless.
As a reminder, below are the ENAC limitations for non-critical operations, i.e. it is not possible to fly:
- on gatherings of people
- less than 150 meters from congested areas-buildings
- less than 50 meters from uninvolved people
- at a maximum height of 120 meters above the ground (A.G.L. – Above Ground Level)
Less restrictive rules are applied for critical operations, especially with reference to standard scenarios, but as already mentioned for critical operations, a certificate is required.
In this first part dedicated to inspections with drone we saw the requirements required of a drone for inspection and those required of the pilot (certificate of critical operations), also broadening the horizons about the use of 300 gram drones. In the next article, the types of inspections that can be carried out with the help of a drone will be discussed.
To know the fields of application of the inspection with drone read the article “Drone ispections – Applications fields” from the Blog.
Note regarding the images: Some of the images in the post are taken from pixabay.com, they are free for commercial use without attribution request; the author who is the legitimate owner is however mentioned for each image. Two other images are taken from the DJI Store site which is the legitimate owner. The use of the images is exclusively for the purpose of a better understanding of the contents of the article. The highlighted image is taken from pixabay.com free for commercial use and without attribution request, the author is Pexels.
Last Updated on/Ultimo aggiornamento – 28/07/2020