Development of the measurement device for position and posture of machine tools by using parallel mechanism

• Project/Area Number: 17560108
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Production engineering/Processing studies
• Research Institution: Osaka Institute of Technology
• Principal Investigator: IHARA Yukitoshi Osaka Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (90213199)
• Project Period (FY): 2005 – 2006
• Project Status: Completed (Fiscal Year 2006)
• Budget Amount: ¥3,400,000 (Direct Cost: ¥3,400,000); Fiscal Year 2006: ¥800,000 (Direct Cost: ¥800,000); Fiscal Year 2005: ¥2,600,000 (Direct Cost: ¥2,600,000)
• Keywords: Machine tool / Numerical control / Parallel mechanism / Motion accuracy / Multi-axis machine tool / Degree of freedom / Positioning

Research Abstract

(1) Remodeling of experimental measurement device
Because a new strong, permanent magnet for the magnetic socket that was used for the joint, a new magnetic socket joint was designed. The newly designed joint did not come to apply and to adjust it in an actual measuring instrument. However, it was found to have enough force for retaining the sensors and struts. It seems that the improvement of the magnet material will advance in the future. It seems that this measuring device has a good prospect.
(2) Comparison with Stewart platform type measuring device
The Stewart platform, known well as generally six degree of freedom-parallel mechanism was investigated and the change in the composition of the measuring device was examined. It was found that the motion range will become uniform compared with a current structure and that the coordinates calculation becomes complex. Moreover, it will be necessary to clarify the accuracy of the measuring device, which is one of the most important factors, because it is still unknown.
(3) Sampling speed improvement of measuring device
Because the current measuring device uses the timer of operating system, the sampling interval was not adjusted to less than 10ms. Then, if the memory function of the measurement interface could be used, the sampling interval was adjusted to 100□s or less, and a basic confirmation was done. As a result, it is possible to take a lot of measurement points when measuring it at a high-speed feed by a small radius for instance, and more information on the machine will be revealed.
(4) Presentation of study results by international meetings
The research results were presented in an international meeting in Japan in the middle of July. They were also presented in another international meeting in Brazil in the middle of September. The opinions of this research were obtained in the meetings.