2D and 3D laser profilometers and industrial scanners are non-contact systems for acquiring geometric profiles, used for the dimensional inspection of surfaces, shaped profiles, weld beads, extrusion cross-sections and complex free-form components. They generate a complete 2D profile scan of a cross-section (by projecting a laser line and using a camera in triangulation) or a 3D point cloud (by scanning the laser line linearly or rotationally over the workpiece). They are indispensable in the quality control of aerospace, automotive and railway components, in industrial robotics and for reverse engineering applications.
Would you like help choosing the right product ?
2D laser line profilometers
The 2D profilometer projects a laser line onto the surface of the workpiece and uses a high-resolution camera to capture the image of the line as deformed by the geometry of the part. A triangulation algorithm converts that deformation into a dimensional profile, providing thousands of points per profile at rates up to several kHz. Typical resolutions are 5-50 μm on the X coordinate and 1-10 μm on the Z coordinate (depth), with working fields from a few cm to over 1 meter. Blue laser sources (405 nm) are better suited to hot, organic or reflective objects.
3D scanners
3D systems are obtained by combining a 2D profilometer with a motion system (motorized linear axis, rotation of the workpiece, robot arm). Superimposing successive profiles generates a three-dimensional point cloud which, processed with dedicated software, provides polygon meshes usable for comparison with the nominal CAD, tolerance calculation and the generation of inspection reports. Advanced 3D systems work with multi-frame structured light, fringe projection or stereoscopy, reaching sub-micrometer accuracies over contained working volumes.
Applications
2D profilometers are used to inspect weld beads (height, width, profile, presence of defects), to measure rubber gaskets and profiles, to check extrusion shapes, to inspect rails and railway profiles and to inspect films and webs. 3D scanners are applied in the dimensional inspection of turbine blades, automotive suspensions, aerospace parts, molds and dies, prototypes, medical devices and prostheses, and works of art and cultural heritage. Reverse engineering of components without a technical drawing is one of the most widespread applications.
Software and workflow
The dedicated software manages calibration of the system (calibration targets and rectification algorithms), acquisition and recording of profiles, noise filtering, alignment with the nominal CAD (best-fit, RPS, datum), comparison with GD&T tolerances, generation of color deviation maps and photorealistic reporting. Export in standard formats (STL, OBJ, IGES, STEP, DXF) enables integration with third-party CAD/CAM software. Advanced functions include mesh decimation, hole filling and surface reconstruction from the point cloud.
Standards and selection
Optical 3D systems are characterized metrologically in accordance with VDI/VDE 2634 parts 2 and 3 (acceptance testing, verification). Calibration uses ball bars and ball plates certified to ISO 17025. The choice depends on the dimensions of the working volume, on the resolution required, on the characteristics of the surface (reflectivity, color, texture), on integration with robot arms or motorized axes, and on the management software.
The development of Industry 4.0 has seen the spread of robotic profilometric systems: the 3D sensor is mounted on an anthropomorphic robot arm that automatically scans complex parts, producing the complete digitization of the product and the comparison with the nominal CAD in a few minutes.
You must be logged in to post a comment.