Feed Rate Control Using Fuzzy Reasoning for a Mold Polishing Robot
Fusaomi Nagata*, and Keigo Watanabe**
*Fukuoka Industrial Technology Center, 3-6-1 Norimatsu, Yahatanishi, Kitakyushu, Fukuoka 807-0831, Japan
**Graduate School of Science and Engineering, Saga University, 1 Honjomachi, Saga 840-8502, Japan
Reducing time cost of polishing process is a major issue in metallic mold manufacturing. The feed rate, i.e., tangential velocity, of a polishing robot is generally limited to maintain stable contact with workpieces having a large curvature. We propose a feed rate generator using fuzzy reasoning for polishing robots that regulates the feed rate along free-formed surfaces appropriately. The smaller the curvature of the model designed by a 3D CAD, the larger the distance between two adjacent cutter location data (CL data) steps generated by the main processor of CAM. Therefore, given curvature results in acquiring the distance between two adjacent steps of CL data. We also propose a hybrid position/force controller with the feed rate generator enabling the robot to conduct polishing efficiently. Experiments show promising results.
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