Due to an ever-increasing variety of parts in production, the programming of robots becomes more and more complex. For the optical quality control of contours with image processing systems, these robots must be individually programmed. The goal of this work is therefore to simplify the programming of the robot. The work has shown that this is possible through discrete real-time and model independent control. The contour is measured by a 3D triangulation sensor whose data is evaluated by an image processing system. Communication with the robot's system takes place via a Profinet interface to ensure real-time capability. The development of the controller has shown that a classical PID-Controller does not provide the desired control quality in particular in the presence of disturbances such as roughness of the surface to be inspected. Instead, a better result could be achieved with a particular switching Sliding Mode Control (SMC) approach that switches back and forth between two surfaces depending on the distance to the surface.