Free use Resource from Pixabay, edited by me with Power Point.
Hello friends, here I am with another curious publication
Like any teacher, I have always liked to make a brief introduction and clarification of concepts before developing a topic, and I start with some basics concepts:
A topographic study is a representation of the surface of a terrain, where the surface extension and the different heights or levels in precise detail of the terrain are graphically described
The simplest expression of this graphic representation is the well-known altimetry drawings (plans), and they are made in urban environments, for cadastral information and detail, for construction, and there are others for specific uses such as those that represent the hydrography of a basin.
Resource
After all, a topographic data (survey) is a really complex design where precision is the key. About 30 years ago, in Venezuela they were carried out through the use of analog equipment such as “Levels equipment and Theodolites”, then with the passage of time high-end equipment such as the so-called "Total Station" began to be used, whose function is summarized to measure distances, levels, angles and inclinations by means of a microprocessor incorporated into the equipment.
About 5 years ago, innovation arrived, in Venezuela specialized drones began to be used for aerial photogrammetric studies to obtain good quality topographic information in less time.

Basically, how is a topographic survey carried out??
In short, the usual practice that I know in the first person, a certain amount of observers and operators is needed, either to manipulate the equipment: total station, GPS and scopes. Obviously the work requires extensive field trips to obtain the aforementioned graphic representation, which means a great investment of time.
Currently, with the use of special drones for topographic studies equipped with high precision cameras, it no longer requires a large number of people, at least 2 operators, one to control the equipment and the other to monitor and give "flight instructions" In the same sense, this job requires less time.
The information obtained, which are thousands of points with information in the 3 dimensions (X, Y, Z), is used to establish georeferences, to obtain dimensions such as areas and volumes, it can be attributed scales of representation, among other characteristics, all this through the use of applications and software like those of the giant Autodesk (they are my favorites).

Advantages and disadvantages of using drones in topographic studies:
Not everything is as good as it seems, I always reserve a very small margin of doubt, so it should always be taken into account that there will be its pros and cons. For example:
Among the known advantages, we can mention:
- The reduction of working time means a reduction in costs and it can also be said that it is more productive in time and money.
- The reduction of personnel to only a minimum of 2 operators, means a reduction in costs and a reduction in occupational risks, there are fewer people on the task and this activity does not require the full field trip that was previously customary.
- You get more data, which is assumed to be higher precision, up to a point.
And in the disadvantages, we will find:
- The autonomy of the equipment is limited to the duration of the battery.
- Flight heights are subject to the manufacturer and to legal provisions in each country, so on average it would not be more than 120 meters high.
- Particularly in Venezuela you must have an aeronautical license, by passing a theoretical and practical exam, although this is not a big problem in any case.
- Worse without a doubt, the disadvantage that I personally find is in the precision, where an overall deviation of up to 10 cm can be handled on average. That, compared to using a total station, 10 cm with a drone is a very high deviation.
But science and technology do not stop, as I write this post, the advances to improve the applications, accuracies and use of Drones in topographic studies, are advancing by leaps and bounds.
And in fact, this is only one of the applications of Drones in engineering, within the multiple uses we can mention the case of inspection of structures, control of the phases and stages of a construction, and they are also very useful in the cases of review and control of impacts to the environment.
Would you like to explore your environment with a drone?
"All the text has been written according to my professional experience as an engineer, university professor, researcher and developer of engineering projects."


