JSSS Journal of Sensors and Sensor Systems JSSS J. Sens. Sens. Syst. 2194-878X Copernicus Publications Göttingen, Germany 10.5194/jsss-3-87-2014 Chain of refined perception in self-optimizing assembly of micro-optical systems Haag S. 1 Zontar D. 1 Schleupen J. 1 Müller T. 1 Brecher C. 2 Fraunhofer Institute for Production Technology IPT, Aachen, Germany Chair at the Laboratory for Machine Tools and Production Engineering (WZL) at RWTH Aachen University, Aachen, Germany 14 04 2014 3 1 87 95 Copyright: © 2014 S. Haag et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://jsss.copernicus.org/articles/3/87/2014/jsss-3-87-2014.html The full text article is available as a PDF file from https://jsss.copernicus.org/articles/3/87/2014/jsss-3-87-2014.pdf

Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements – especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.

 References Bradski, G.: The OpenCV Library, Dr. Dobb's Journal of Software Tools, 2000. Brecher, C. (Ed.): Integrative production technology for high-wage countries, Berlin, New York, Springer, 2012. Brecher, C., Pyschny, N., Haag, S., and Lule, V.: Micromanipulators for a flexible automated assembly of micro optics, in SPIE Photonics Europe, International Society of Optics and Photonics, 2012. Brecher, C., Pyschny, N., and Bastuck, T.: Design and Optimization of Flexure-Based Micro- manipulator for Optics Alignment, in: Proceedings of the 13th International Conference of the European Society for Precision Engineering and Nanotechnology, edited by: Leach, R., 27–31 May, 268–271, 2013. Firestone, L., Cook, K., Culp, K., Talsania, N., and Preston Jr., K.: Comparison of autofocus methods for automated microscopy, Cytometry, 12, 195–206, 1991. Haag, M. and Härer, S.: SCALAB. Scalable Automation for Emerging Lab Production, Final report of the MNT-ERA.net research project, 2012. Laganière, R.: OpenCV 2 computer vision application programming cookbook, Packt. Publ. Limited, 2011. Loosen, P., Schmitt, R., Brecher, C., Müller, R., Funck, M., Gatej, A., Morasch, V., Pavim, A., and Pyschny, N.: Self-optimizing assembly of laser systems, Prod. Engineer., 5, 443–451, 2011. Miesner, J., Timmermann, A., Meinschien, J., Neumann, B., Wright, S., Tekin, T., Schröder, H., Westphalen, T., and Frischkorn, F.: Automated Assembly of fast-axis collimation (FAC) lenses for diode laser bar modules. High-power diode laser technology and applications VII, edited by: Zediker, M. S., San Jose, CA, 24 January 2009: SPIE (v7198), 71980G-71980G-11, 2009. Nayar, S. and Nakagawa, Y.: Shape from focus: An effective approach for rough surfaces, in Robotics and Automation Proceedings, IEEE International Conference, 218–225, 1990. Pierer, J., Lützelschwab, M., Grossmann, S., Spinola Durante, G., Bosshard, Ch., Valk, B., Brunner, R., Bättig, R., Lichtenstein, N., Zediker, and Mark S.: Automated assembly processes of high power single emitter diode lasers for 100W in 105 μm/NA 0.15 fiber module. High-power diode laser technology and applications IX, edited by: Zediker, M. S., 23–25 January 2011, San Francisco, California, United States, Bellingham, Wash: SPIE (v. 7918), 79180I-79180I-8, 2011. Russell, S. J., Norvig, P., and Davis, E.: Artificial intelligence. A modern approach, 3rd Edn., Upper Saddle River, NJ, Prentice Hall, 2010. Schmitt, R., Pavim, A., Brecher, C., Pyschny, N., Loosen, P., Funck, M., Dolkemeyer, J., and Morasch, V.: Flexibel automatisierte Montage von Festkörperlasern. Auf dem Weg zur flexiblen Montage mittels kooperierender Roboter und Sensorfusion, wt Werkstatttechnik online, Vol. 98, No. 11/12, 955–960, 2008. Whitney, D. E.: Mechanical assemblies. Their design, manufacture, and role in product development, New York: Oxford University Press, 2004.