Topographic survey with aerial LiDAR
Introduction
Topography (from the Greek τόπος tópos 'place' and γραφία graphy 'description') is the science that studies the set of principles and procedures that aim to graphically represent the Earth, with its shapes and details; both natural and artificial; (see planimetry and altimetry). This representation takes place on flat surfaces, limited to small areas of land, using the name "geodesy" for larger areas. Very simply, it can be said that for a surveyor the Earth is flat (geometrically), while for geodesy it is not.
For this, a three-dimensional coordinate system is used, with x and y being the responsibility of planimetry, and z being the responsibility of altimetry.
Topographic maps use the representation system "of bounded planes"), showing the elevation of the terrain using lines that connect points with the same elevation with respect to a reference plane, called contour lines, in which case the map is said to be hypsographic. Said reference plane may be sea level, and if so, we will speak of altitudes instead of elevations.
Field of action
Surveying is essential in several fields; For example:.
Topographical work
Topography is a geometric science applied to the description of the surrounding immobile physical reality. It is to capture on a topographic plane the reality seen in the field, in the rural or natural environment, of the earth's surface; In the urban area, it is the description of the existing facts in a given place: walls, buildings, streets, among others.
Topographic work can be divided as two congruent activities: taking "the terrain to the office" (by measuring points or surveying,[1] its file in electronic instruments and then editing it on the computer) and taking "the office to the terrain" (by staking out the reverse path, from a project on the computer to its location using points on the terrain). The surveyed or staked points have a three-dimensional value; That is, the location of each point is determined in the horizontal plane (two dimensions, north and east) and in height (third dimension).