The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 2016
Filed:
Sep. 02, 2014
The University of Tokyo, Tokyo, JP;
Dmg Mori Seiki Co., Ltd., Nara, JP;
Hiroshi Fujimoto, Tokyo, JP;
Hongzhong Zhu, Tokyo, JP;
Koji Yamamoto, Nara, JP;
Shinji Ishii, Nara, JP;
DMG MORI SEIKI CO., LTD., Nara, JP;
THE UNIVERSITY OF TOKYO, Tokyo, JP;
Abstract
A controller has a control unit generating a control signal to control a drive motor and a friction compensation unit adding a friction compensation signal to the control signal for compensating for a positioning error caused by friction in a guide unit. When reversing the direction of movement of the movable body, the friction compensation unit generates a friction compensation signal in accordance with a function f(α) representing a friction compensation value uf by a relationship with a variable α and asymptotically approaching the maximum value and the minimum value of the friction compensation value uf and having an inflection point therebetween, and adds the generated friction compensation signal to the control signal generated by the control unit during movement of the movable body a predetermined movement distance from before to after the reversing.