With a certain nostalgia, we remember when we used to compete with some colleagues to see who could achieve the best ratio between observed points and time during the execution of a topographic survey, or who could set up an instrument the fastest. Back then, many geomatics engineers were defined or "measured" by their efficiency in the field, as "measuring well" was highly valued. This evaluation parameter accompanied several generations of geomatics professionals, who achieved a high level of specialization in the most traditional field procedures, such as conducting topographic surveys in their broadest sense. However, this situation largely overshadowed an equally or even more important task related to data processing, which can be summarized from data download to the generation of final products.

While data analysis has always been present, nowadays, working with data and drawing conclusions from its processing is one of the most significant activities in any engineering specialty: from price analysis to complex research, efforts are focused on data processing. In this context, geomatics intrinsically possesses all the conditions to view data analysis as an important line of work that can be further developed. This is evident when analyzing our training: compensation of leveling or traverses, direct or inverse geodetic problems, varieties of reductions, network adjustment, aerotriangulation in photogrammetry, or geospatial analysis.

Currently, technological development has changed the scenario for geomatics professionals. A high degree of automation in geodetic observation platforms, coupled with intensive development in the communications area, has shifted the focus of technologies, which no longer specifically target a skill in the operator. For example, for colleagues who scan, we do not believe that the number of stations performed per unit of time is an efficiency parameter, since the objective of that task is not the application of the technique, but rather the acquisition of data for the resolution of some problem presented by the industry.

Thus, while being "skilled" with an instrument is important, it is no longer a dominant factor compared to "data processing." This is mainly due to efficient learning curves for geodetic observation instruments, coupled with the automation of more traditional procedures. Let's take another common example for many: observing angles and distances from a repeated process. The method of reiteration, as it was formerly known, consists of observing a series of targets on both faces of the total station (or theodolite on many occasions) first in direct mode in ascending order and then in transit mode in descending order. The application of this technique was widely used in triangulation networks where four series were observed, while in astronomical determinations 16 series were performed. This observation depended entirely on the operator's faculties and skills: in reality, we are talking about the art of measurement. Many will remember concepts such as peineteo in old instruments or, definitively, choosing certain time slots in which the thermal gradient does not affect the observation of a sighting.

Knowing this and having provided support to many colleagues, we have confirmed that it is truly impossible to beat the machine (referring to the total station). Now, we are specifically referring to a total station with automatic aiming. At Trimble, automatic aiming systems are divided into two technologies. The first is called Autolock and is useful for performing observation rounds to prisms where the operator's skill is replaced by a tracking system based on reflectivity. On the other hand, Autolock has dynamic applications as it allows prism tracking. Finally, Finelock is a more precise version of Autolock with direct application in engineering and geomonitoring.

In a study carried out in 2014, we empirically determined that using Autolock, a round of prisms can be observed in one-third of the time it takes for a human to perform the observation (see Validation of automatic aiming in topographic surveys, C. Aguilar, F. Carvajal). While this points to an optimization of the process in terms of productivity, there is also an increase in precision compared to a manual observation. Some aspects that improve the precision of the observation process using stations with automatic aiming systems are related to the consequences of the technology. This may sound contradictory, but when technically analyzing Autolock or FineLock, their use eliminates systematic errors inherent in the observation. To exemplify this, we can consider a traditional scenario such as a topographic survey. The heat emanating from the Earth's surface produces a negative effect on the direct observation of a target with a total station, an effect called thermal turbulence. The interesting thing about this is that Trimble's automatic aiming systems are, to a large extent, immune to this condition, due to the operating frequency of the tracker. In other words, the robot does not get tired and has an "eye" that can track the prism under any condition.

Precisely this is the basis of automatic observation with a total station and puts us in a good moment to define geomonitoring. The definition considers the integration of geodetic and geotechnical sensors applied to the geospatial control over time of various artificial or natural structures. This definition, in technological terms, raises the need for the following qualities: precision, reproducibility, and automation. These characteristics are achieved by using instruments such as total stations with automatic aiming systems, coupled with powerful processing software like Trimble Access for periodic campaigns and Trimble 4D Control for continuous campaigns. To exemplify again: the total station can perform observation rounds to a series of targets, determining coordinates based on a time series automatically. This task is crucial when understanding the deformation and/or displacement of a structure, as it establishes a trend that is contrasted with geotechnical information, creating evidence of utmost importance for decision-making.

Now, what is the role of geomatics in this activity? The truth is, the answer can be very broad. First, the approaches change a bit; let's consider that automation addresses continuous observation, allowing more time to delve into other activities such as the geometric aspect, that is, designing the most suitable geodetic network that, based on automated observations, allows for the identification of displacements of the points to be monitored. In this same sense, analysis is favored by automation, as we have a significant volume of data that allows not only the determination of coordinates but also their quality through the calculation of the posterior variance-covariance matrix after an adjustment process, which is also automated, enabling analyses aimed at determining the structure's deformation and generating information for multidisciplinary teams.

Currently, many engineering projects require geomonitoring solutions. However, one of the problems we have detected is the disconnect between geomatics professionals and available technology or its implementation, not only in technological terms but also in a theoretical sense. Consequently, at GEOCOM, we constantly work on generating material that can serve as a guide for addressing different geomonitoring projects. Finally, we have no doubt that geomonitoring is an activity where surveying and geomatics can contribute tremendously, provided that the activity is associated with creating value not through the instrument, but through its results.

Ariel Silva, Felipe Carvajal - Geocom Support