2006 Fiscal Year Final Research Report Summary
Development of a surface encoder for next generation three-axis precision stages
| Project/Area Number |
14102017
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (S)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Intelligent mechanics/Mechanical systems
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
KIYONO Satoshi Tohoku University, Graduate School of Engineering, Professor, 大学院工学研究科, 教授 (40005468)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
GAO Wei Tohoku University, Graduate School of Engineering, Associate Professor, 大学院工学研究科, 助教授 (70270816)
YAMANAKA Masashi Tohoku University, Graduate School of Engineering, Associate Professor, 大学院工学研究科, 助教授 (20292229)
JU Bingfeng Tohoku University, Graduate School of Engineering, Research Associate, 大学院工学研究科, 助手 (10431529)
SHIMIZU Hiroki Kyushu Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (50323043)
|
|---|
| Project Period (FY) |
2002 – 2006
|
| Keywords | position measurement / surface motor / multi-degee-of-freedom / slope / angle grid / closed-loop control / sensor / accuracy |
|---|
| Research Abstract |
This research has developed a surface encoder consisting of a sinusoidal angle grid and a two-dimensional slope sensor for multi-degree-of-freedom planar motion measurement. The angle grid has a three dimensional micro-structured surface, which is a superposition of periodic sinusoidal waves in the X-and Y-directions. The laser-based slope sensor is used to read local slope profiles of the grid surface. The X-and Y-positions together with tilt motions about the X-, Y-and Z-axes can be detected by using multiple sensors with a maximum speed of 550mm/s. a double pass surface encoder for nanometer position measurement in the XY plane. By using a double pass optical layout, the sensitivity of the sensor becomes twice as much as that of the single pass surface encoder. A resolution of 2 nm has been realized.
Diamond turning with a fast tool servo has been chosen as the fabrication method for the angle grid. The constructed fast tool servo, which employs a piezoelectric tube actuator to actua
… More
te the diamond tool and a capacitance probe as the feedback sensor, was confirmed to have a bandwidth of approximately 4 kHz and a tool displacement accuracy of several nanometers in the closed-loop mode. An evaluation technique based on the two-dimensional discrete Fourier transform (DFT) of interference microscope images has been developed to evaluate the fabricated grid surface effectively. The fabrication result of a grid surface over an area of φ150 mm has indicated the effectiveness of the fabrication system. The fabricated minimum pitch of the angle grid is 10 μm. A UV roller replication technique has also been developed to fabricate the angle grid on large area films.
The surface encoder has been applied for surface motor-driven stages for five degree-of-freedom precision positioning. The surface motor consists of pairs of linear motors placed on the same surface. The magnetic array and the stator winding of the linear motor are mounted on the platen (the moving element) and the stage base, respectively. The angle grid of the surface encoder is mounted on the platen of the stage which is levitated by air-bearings. The slope sensors and the air-bearing pads are fixed on the stage base so that the motion of the platen is not affected by the electronic cables and air hoses. The surface encoder has also been applied to Sawyer motor driven stages. Less
|
