Relative range error evaluation of terrestrial laser scanners using a plate, a sphere, and a novel dual-sphere-plate target
Balasubramanian Muralikrishnan, Prem K. Rachakonda, Vincent D. Lee, Katharine M. Shilling, Daniel S. Sawyer, Geraldine S. Cheok
Terrestrial laser scanners (TLS) are a class of 3D imaging systems that produce a 3D point cloud by measuring the range and two angles at different sampling locations. The ranging unit of a TLS realizes the SI unit of length. Relative range error is one component of the overall range error of TLSs and its estimation is therefore an important aspect in establishing metrological traceability of measurements performed using these systems. Target geometry is an important aspect to consider when realizing the relative range tests. The recently published ASTM E2938-15 mandates the use of a plate target for the relative range tests. While a plate target may reasonably be expected to produce distortion free data even at far distances, the target itself needs careful alignment at each of the relative range test positions. In this paper, we discuss relative range experiments performed using a plate target and then address the advantages and limitations of using a sphere target. We then present a novel plate-sphere target that draws from the advantages of the sphere and the plate without the associated limitations. The spheres in the plate-sphere target are used simply as fiducials to identify a point on the surface of the plate that is common to both the scanner and the reference instrument, thus overcoming the need to carefully align the target.
, Rachakonda, P.
, Lee, V.
, Shilling, K.
, Sawyer, D.
and Cheok, G.
Relative range error evaluation of terrestrial laser scanners using a plate, a sphere, and a novel dual-sphere-plate target, Measurement, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=922369
(Accessed December 2, 2023)