Research and Development in Measurement and Testing Technology

Automatic and Fast Point Cloud Analysis and Evaluation

Non-contact optical methods of 3D digitization have replaced conventional methods in many applications. Regardless of whether the triangulation sensors operate with points, lines or planes – many millions of measured 3D data are generated in a few seconds. These data deliver a description of a digitized component’s surface topography. Verification of a component’s dimensional accuracy based on these data, e.g. for quality assurance tasks, requires methods and algorithms that evaluate and analyze the 3D data in order, for instance, to determine deviations in dimensions, shape and position from a standard model.

Established point cloud processing programs that determine the desired geometric parameters manually and interactively are available for offline analysis. Systems integrated in production require rapid, automatic and integrated data evaluation, however. The measured 3D data processing package OptoInspect Inline was developed for this purpose. It consists of a function library and a graphic development and test environment.

The library can be integrated in applications of one’s own and supplies methods for point cloud processing for various tasks:

Methods for Measured 3D Data Processing

• Alignment, referencing and proximity determination of data sets
• Approximation of geometric primitives (2D and 3D standard geometric elements)
• Automatic data segmenting
• Determination of measured variables from the geometric primitives’ parameters
• Thinning, homogenization and smoothing

A graphic development environment is available to develop and test applications of one’s own.

Library Features

• Algorithms as a library conforming to C
• Speed through multicore support and efficient data structures
• Processing of large quantities of points
• Development and test environment with visualization based on openGL
• Compatibility with current Windows operating systems

In January 2014 the German National Metrology Institute (Physikalische-Technische Bundesanstalt PTB) certified the Fraunhofer IFF software library »OptoInspect Inline«. They attested: »All results obtained with the software under test deviated from the PTB results by less than 0,1 µm in length features and 0,1" in angular features. The software has therefore been placed in the class of the smallest deviations«.