Evaluation of Metallic Mold Surfaces Polished by an Industrial Robot with Stick Whetstones
Koji Shibuya and Shunsuke Issiki
Ryukoku University, 1-5 Yokotani, Seta-Oe, Otsu, Shiga 520-2194, Japan
Our ultimate goal is to develop an automatic polishing system that uses an industrial robot equipped with whetstones. The robot mimics the movements skilled workers make as they polish surfaces manually. This paper, the first step in the development of our system, presents experimental results to prove that our system completely removes the marks, which is the most time-consuming and crucial process for human workers, from the flat surfaces of metallic molds produced through the Electrical Discharge Machining (EDM) process. We build a polishing system that consists of a small 6-DOF industrial robot for material handling. Attached to its wrist is a six-axis force-torque sensor and it employs a whetstone holding mechanism. Before the robot system begins its polishing work, the normal force to be applied to the flat surface can be adjusted to a target value by altering the height of the hand. We adopt two polishing paths for the whetstone, reciprocating and zigzag. We then conduct experiments using the two paths, visually inspect the surface, and measure the surface roughness and shape. Based on the experimental results, we confirm that the system has completely removed the EDM mark layer. Although we find that the zigzag path leaves striped patterns on the polished surface, we are not able to determine their cause. Finally, we test three combinations of the two paths under different conditions to find the most suitable combination.
-  T. Ito and K. Morishige, “Polishing Process Automation by Industrial Robots with Polished Surface Quality Judged Based on Imaging Processing,” Int. J of Automation Technology, Vol.3, No.2, pp. 130-135, 2009.
-  H. Suzuki, “Multi-Axis Controlled Ultraprecision Machining and Measurement,” Int. J of Automation Technology, Vol.3, No.3, pp. 227-232, 2009.
-  M. Anzai, T. Nakagawa, N. Yoshioka, and S. Ganno, “Development of Inline Micro-Deburring Applying Magnetic-Field-Assisted Polishing,” Int. J of Automation Technology, Vol.4, No.1, pp. 9-14, 2010.
-  K. Takahashi, “Deburring Finishing Using a Magnetic Polishing Machine,” Int. J of Automation Technology, Vol.4, No.1, pp. 33-37, 2011.
-  K. Kimura, P. Khajornrungruang, T. Okuzono, and K. Suzuki, “Evaluation Method Applying Fourier Transform Analysis for Conditioned Polishing and Surface Topography,” Int. J of Automation Technology, Vol.5, No.2, pp. 173-178, 2011.
-  H. Fujimoto, A. Waseda, and X. Zhang, “Profile Measurement of Polished Surface with Respect to a Lattice Plane of a Silicon Crystal Using a Self-Referenced Lattice Comparator,” Int. J of Automation Technology, Vol.5, No.2, pp. 179-184, 2011.
-  P. Khajornrungruang, N. Wada, K. Kimura, R. Yui, and K. Suzuki, “Investigation on Slurry Flow and Temperature in Polishing Process of Quartz Glass Substrate,” Int. J of Automation Technology, Vol.5, No.2, pp. 195-200, 2011.
-  S. K. Chee, H. Suzuki, J. Uehara, T. Yano, T. Higuchi, and W. Lin, “A Low Contact Force Polishing System for Micro Molds That Utilizes 2-Demensional Low Frequency Vibrations (2DLFV) with Piezoelectoric Actuators (PZT) and aMechanical Transformer Mechanism,” Int. J of Automation Technology, Vol.7, No.1, pp. 71-82, 2013.
-  K. Okamoto, Y. Nakagawa, K. Minowa, N. Okina, M. Sakurai, and S. Osako, “Grinding robot on a crooked spatial surface,” Proc. of Int. Symposium on Industrial Robots, 7, 615-622, 1977.
-  T. Izumi, T. Narikiyo, and Y. Fukui, “Teachingless grinding robot depending on three force information,” Advanced Robotics, Vol.2, No.1, pp. 55-67, 1987.
-  Y. Mizugaki and M. Sakamoto, “Development of a Metal-Mold Polishing Robot System with Contact Pressure Control Using CAD/CAM Data,” Annals of the CIRP, Vol.39, No.1, pp. 523-526, 1990.
-  Y. Takeuchi, N. Asakawa, and D. Ge, “Automation of Polishing Work by and Industrial Robot (System of Polishing Robot),” JSME Int. J., Series C, Vol.36, No.4, pp. 556-561, 1993.
-  Y. Takeuchi, D. Ge, and N. Asakawa, “Automated Polishing Process with a Human-like Dexterous Robot,” Proc. of Int. Conf. on Robotics and Automation, 3, 950-956, 1993.
-  F. Nagata, K. Watanabe, Y. Kusumoto, K. Tsuda, K. Yasuda, K. Yokoyama, and N. Mori, “New Finishing System for Metallic Molds Using a Hybrid Motion/Force Control,” Proc. of the 2003 IEEE Int. Conf. on Robotics & Automation, Taipei, 2171-2175, 2003.
-  F. Nagata, et al., “High Precision Polishing Robot Using a Learning-Based Surface Following Controller,” Proc. of 2003 IEEE Int. Symp. on Computational Intelligence in Robotics and Automation, Kobe, 91-96, 2003.
-  F. Nagata and K. Watanabe, “Feed Rate Control Using Fuzzy Reasoning for a Mold Polishing Robot,” J. of Robotics and Mechatronics, Vol.18, No.1, 2006.
-  J. Guo, H. Suzuki, and T. Higuchi, “Development of micro polishing system using a magnetostrictive vibrating polisher,” Precision Engineering, Vol.37, pp. 81-87, 2012.
-  J. P. Huissoon, F. Ismail, A. Jafari, and S. Bedi, “Automated Polishing of Die Steel Surface,” Int. J. of Advanced Manufacture Technology, Vol.19, pp. 285-290, 2002.
-  M. J. Tsai, J.-L. Chang, and J.-F. Haung, “Development of an AutomaticMold Polishing System,” IEEE Trans. on Automation Science and Engineering, Vol.2, No.4, pp. 393-397, 2005.
-  M. J. Tsai and J. F. Huang, “Efficient automatic polishing process with a new compliant abrasive tool,” Int. J. of Advanced Manufacturing Technology, Vol.30, pp. 817-827, 2006.
This article is published under a Creative Commons Attribution-NoDerivatives 4.0 Internationa License.