Measuring Human-made Corner Structures with a Robotic Total Station using Support Points, Lines and Planes

Measuring non-planar targets with a total station in reflectorless mode is a challenging and error-prone task. Any accurate 3D point measurement requires a fully reflected laser beam of the electronic distance meter and proper orientation of the pan-tilt unit. Prominent structures like corners and edges often cannot fulfill these requirements and cannot be measured reliably. We present three algorithms and user interfaces for simple and efficient construction-side measurement corrections of the systematic error, using additional measurements close to the non-measurable target. Postprocessing of single-point measurements is not required with our methods, and our experiments prove that using a 3D point, a 3D line or a 3D plane support can lower the systematic error by almost a order of magnitude.