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Self-calibration and evaluation of the Trimble GX terrestrial laser scanner

There are numerous imaging modalities for reconstructing 3D object space on the market. Among all the varieties, which include 3D TOF range cameras, structured light systems, and traditional photogrammetric systems, terrestrial laser scanners have gained the most attention and demand from the surveying and engineering discipline. This is probably because of the large field of view and rapid dense data acquisition offered by most modern terrestrial laser scanners. As terrestrial laser scanning is gaining popularity, it is faced with new challenging tasks that demand higher accuracy such as deformation monitoring and other precise engineering applications. To ensure the highest quality point cloud is captured, quality assurance techniques that can be self-deployed before every accuracy demanding application are necessary. The laboratory calibration offered by the manufacturer requires the scanner to be shipped away for weeks, which is too time consuming and expensive to be done frequently. The preferred approach is through a user self-calibration routine. This paper presents the results from two point-based self-calibration campaigns of the Trimble GX, which is Trimble’s latest pulse-based hybrid type terrestrial laser scanner on the market. * Corresponding author.