Events

Technology Lecture: Advanced Measurement Technology and Applications

Date: 15 Jul 2008 - 15 Jul 2008

Venue: SIMTech Training Room, Level 3, Tower Block

Abstract
(1) MEMS Motion Measurement and Modal Analysis Based on Doppler
     Interferometry
Micro-Electro-Mechanical Systems have been growing rapidly over recent years. However, measurement of their motions is a difficult problem. A laser Doppler interferometric system for measuring both the in-plane and out-of-plane motions of vibrating combs in MEMS, which can measure the instantaneous velocity and displacement of the periodic and non-periodical motions of the vibrating comb, has been developed. The working principle and optical diagram of the system are explained. The instantaneous velocity and displacement of vibrating combs are acquired by demodulating the frequency-modulated Doppler signal by using a phase-locked loop. The developed laser Doppler interferometer provides a powerful means in studying the performance of the MEMS devices, particularly in studying their vibration modals. Modal analyses of the vibrating comb are carried out theoretically and experimentally. Due to the non-rigid structure of the MEMS resonator besides the basic modal there are also high order modals in the MEMS vibration. The basic modal is the desired in-plane lateral vibration. The second order vibration is a torsion vibration about the axis perpendicular to the teeth of the movable comb. Both third and fourth order vibrations are lateral bending of the supporting beams. The measured experimental data of the basic and high order vibrations are presented. The accuracy of the developed interferometer has been checked by an acceleration calibrator.

(2) The New Developments in Coordinate Measuring Techniques &
     Precision Mechanical System Design
The historical position of coordinate measuring machines (CMMs) and problems needed to be solved are expounded. The working principle and key techniques of intelligent CMMs are discussed. The specific features of the non-orthogonal coordinate measuring systems including cylindrical CMMs, spherical CMMs, articulated arm CMMs, light pen CMMs, triangulation measuring systems and multi-lateration coordinate measuring systems are analyzed. The prospect of non-contact probes, in particular that of confocal probes, in coordinate metrology is demonstrated. The status of researches on nano-CMMs at home and abroad is introduced.

About the Speaker
Professor Zhang Guoxiong is an academic staff at the Department of Precision Instruments, Tianjin University, China. He was conferred an Honorary Doctorate degree by Moscow State University of Technology (Stankin) in 1996. Prior to that, he has held several senior positions, including Chairman of Department of Precision Instrument Engineering, Tianjin University (1986-1995); and Dean of the College of Precision Instrument and Opto-Electronics Engineering, Tianjin University (1995-1997). He was elected as the Chairman of Scientific and Technical Committee on Precision Engineering of International Institution for Production Engineering Research (CIRP) for three years (1994-1997); President of CPEI, Chinese Production Engineering Institution (1995-1999); Chairman, All-China Teaching Guiding Committee on Instruments and Gauges (1996-2001).
 
Professor Zhang has served as a visiting scholar having conducted research collaboration at the National Institute of Standards and Technology (NIST) for three consecutive years (1981 to 1984). He was attached to the University of North Carolina at Charlotte, USA as a visiting professor for 5years (1991, 1998/'99, 2003/04).

He has received numerous awards in recognition of his contribution, including the National Invention Award and six Awards of Advancement for Science and Technology conferred by Ministry of Education in China, Tianjin City and other provinces in China. A joint project with Professor Hocken at NIST, USA won the Award of Excellent Research Achievement conferred by Department of Commerce, USA, for research work on "Software Error Compensation of Coordinate Measuring Machines" in 1983. He has also been awarded the titles of All-China Model Teacher award, Model Worker of Tianjin City, Honorary Expert in Measuring and Testing Technologies and Instruments of Tianjin City in recognition of his outstanding contributions in education and research work. 

He has successfully accomplished 50 projects collaborations inclusive of 12 international cooperation programs and three United Nation Development Programs. He has published 13 books and 450 academic papers.

He has successfully accomplished 50 projects collaborations inclusive of 12 international cooperation programs and three United Nation Development Programs. He has published 13 books and 450 academic papers. 

Programme
1.15pm  : Registration

1.30pm  : Presentation (1)
               Q&A

2.10pm  : Refreshments & Networking

2.30pm  : Presentation (2)
               Q&A

4.00pm  : End

Who Should Attend
Senior managers, engineers, researchers, academic staff members and engineering students.

Registration
Registration for the lecture is free of charge. Seats are available on a first-come, first-served basis.

Enquiries
For technical enquiries, plesae contact
Dr Fang Zhongping, Senior Scientist, Email: zpfang@SIMTech.a-star.edu.sg

For registration & general enquiries, please contact
Alice Koh, Email: alicekoh@SIMTech.a-star.edu.sg