SurfaceControl is based on the principles of deflectometry and fringe projection, which enables even the smallest of surface defects to be recognised reliably, as well as the inspection of surface aesthetics.
The system complements the company’s existing ReflectControl, which is already being used by automotive vehicle manufacturers worldwide, including the likes of Daimler, BMW and Honda. Whereas ReflectControl is designed for the inspection of shiny, reflective, painted surfaces only, SurfaceControl measures against non-reflective surfaces such as matt, plastic, unpainted and bare metal surfaces, making it suitable for automotive press shop and body-in-white applications. However, other industries where high-quality surface finish and consistency are important, such as aerospace manufacturing, will also benefit from the system.
Micro-Epsilon’s SurfaceControl is designed for the inspection of diffuse surfaces such as metals (uncoated, electroplated, EPD), plastics and ceramics. The sensor, which is based on the fringe projection principle, scans the surface and generates a 3D point cloud. This point cloud is subsequently evaluated using specially developed tools in order to recognise extremely small defects and discontinuities on the surface. Sensors with different measuring ranges, areas and resolutions are available to suit any application.
SurfaceControl scans the surface of car body components with a 3D sensor in a few seconds, and offers the detection and evaluation of local defects. A digital stone, for example, is used for the analysis. This block is moved over the 3D data of the surface like a physical block, with the length and direction of the block adjusted according to the shape of the surface. The result is the DefectMap – a graphical representation of the defect with precise information about height and depth. Determined values can be used for an automatic ‘OK/NOK’ quality control decision.
Comprising a 3D smart sensor and two optional software packages, SurfaceControl achieves significantly higher inspection speeds, together with increased measurement accuracy by using a projection unit and newly developed cameras. The modular design of SurfaceControl enables the system to be installed both offline (fixed mount) and as an in-process inspection system (robot-mounted). This technology is already being used by automotive companies to inspect vehicle components such as airbags, dashboard consoles and instrument panels.
The sensors are available for measurement areas of 290 by 210 mm2 up to 570 by 430 mm2, with surface detection typically occurring within 0.5 seconds per measurement area. Achievable lateral resolution is between 0.25 mm for small areas and 0.5 mm for the largest area. As a result, surface deviations from 5 micron in height can be detected reliably. The depth of the measurement area of between 150 and 300 mm also enables reliable detection of zones with a strong curvature. By using planning software based on CAD data, larger test objects are separated into several measuring positions that are approached one after another. The system is designed in such a way that several robots can operate in one cell on the same test object in order to adapt inspection times to suit production cycle times.
Three different versions of SurfaceControl are available. SurfaceControl Robotic is for the inspection of large components. By mounting the sensor head to a robot arm, the system can be quickly adapted to different inspection applications. All six degrees of freedom of the robot are available. Depending on requirements, a robot with a specific radius can be selected. If the component is also positioned on a rotary table (as the seventh axis, for example) it can be turned towards the sensor in such a way that the projection of the robot can be reduced. With SurfaceControl Robotic, the complete inspection of large components using only one sensor is possible.
SurfaceControl Mobile is for the surface inspection of components in different locations. This portable system, which comprises a laptop and sensor mounted on a tripod, can be safely transported to its destination in a carrying case. The standard measuring surface is approximately 410 by 300 mm.
Lastly, SurfaceControl Compact is available for the inspection of small test pieces with dimensions up to 200 by 300 mm. The system is integrated into a protective enclosure/cabinet. Components to be inspected are introduced manually or automatically into the system. SurfaceControl Compact is suitable for the inline inspection of injection-moulded or die-cast components.
