Abstract
There is a growing demand for measurements of natural and built elements, which require quantifiable accuracy and reliability, within various fields of application. Measurements from 3D Terrestrial Laser Scanner come in a point cloud, and different types of surfaces such as spheres or planes can be modelled. Due to the occlusions and/or limited field of view, it is seldom possible to survey a complete feature from one location, and information has to be acquired from multiple points of view and later co-registered and geo-referenced to obtain a consistent coordinate system. The aim of this paper is not to match point clouds, but to show a methodology to adjust, following the traditional topo-geodetic methods, 3DTLS data by modelling references such as calibrated spheres and checker-boards to generate a 3D trilateration network from them to derive accuracy and reliability measurements and post-adjustment statistical analysis. The method tries to find the function that best fits the measured data, taking into account not only that the measurements made in the field are not perfect, but that each one of them has a different deviation depending on the adjustment of each reference, so they have to be weighted accordingly.
Highlights
Caves open to the public constitute an important heritage asset exploited as a tourist resource
Goniometers, compasses, theodolites, tachymeters, total stations, and gyroscopic theodolites have been used for mapping, which were linked to data taken with Global Navigation Satellite Systems (GNSS) in the exterior to be georeferenced [2]
The purpose of this paper is not to create a method for co-registering and georeferencing point clouds, but to extract observations to create a 3D trilateration network to be processed in the way of traditional geodetic networks in order to derive accuracy and reliability measurements and post-adjustment statistical analysis
Summary
Caves open to the public constitute an important heritage asset exploited as a tourist resource. In these circumstances, it is the duty of the competent administration and of all the actors in the tourism industry to ensure the preservation of the assets with their enhancement within the framework of “sustainable tourism” [1]. The cave of El Castillo is included in the World Heritage List, which implies above all a commitment to the responsible and sustainable management of this property, which we should bequeath to future generations in the same state in which it has come down to us from the depths of geological and prehistoric time. Caves are characterised by a series of particularities from a topographical perspective, such as the lack of lighting, almost constant temperature, high humidity, the existence of small spaces, complex access, the relationship between the interior and the exterior, and so on [1].
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have