HoloPort – design and integration of a digital holographic 3-D sensor in machine tools

Abstract

Abstract. Manufacturing of high-precision components requires accuracies that even the most modern processing machines are often unable to deliver reliably. Slightly worn tools, incorrectly calibrated sensors or even different trajectories can lead to results that do not comply with the desired specifications. However, quality control is still mainly performed on randomized samples outside the machine tool in special measuring rooms. Therefore, closed-loop quality control becomes a cumbersome iterative process. With HoloPort, we present a digital holographic sensor system that is capable of measuring the complete topography of machined components with sub-micrometer precision directly inside a tooling machine. To our knowledge, HoloPort is the first wireless interferometric sensor inside a machine tool worldwide. As it is fully integrated, it features not only a multiwavelength interferometer but also a miniaturized graphics processing unit (GPU). This allows for full data evaluation directly in the sensor. A single measurement is taken and processed within 3 s during wireless operation. HoloPort is easy to integrate into a variety of machine tools. This contribution includes detailed information about the sensor architecture. Experimental results on milled parts demonstrate the performance of the system and illustrate possible inline applications as well as future perspectives for the sensor.

Digital holographic measurement system for use on multi-axis systems

“…The focus will be on the collaborative robot UNIVERSAL ROBOT UR16e; first measurements were presented in 12 . In previous studies, the 5-axis machine tool HERMLE C32 U has been introduced and characterized in detail in with our prototype sensor HoloPort 9,13,6 . Measurement results can be found in 2, 5, 14 .…”

Emerging scientific and industrial applications of digital holography: an overview

“…DHI methods have been used for dimensional metrology, surface topography, roughness and form measurements [18-20, 27-30, 137-142]. Application of these methods is also demonstrated for machine tools testing [47,48], photo-polymerization process [143], monitoring of fibers drawn using electrospinning process [144], as potential candidate for onsite studies. With technological advances and development of new manufacturing processes such as additive manufacturing and rapid prototyping, improved quality control and precision measurement methods are required.…”

“…HI precisely measure micro and nanometer displacements [27][28][29][30], vibrations [31,32], refractive index and phase [33,34] and thus find applications in a wide range of processes. Hence, holographic interferometric techniques have been widely used for study and NDT applications including testing and quality control of industrial and scientific products [4,[22][23][24][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54], space and avionic components [42][43][44][45], automotive components [45,46], machine tools [47,48] etc.…”