On the basis of existing techniques, a compact micro-displacement sensor of phase grating interference (PGI) is described, which adopts cylindrical hologram diffraction grating as the calibration standard. The optic...On the basis of existing techniques, a compact micro-displacement sensor of phase grating interference (PGI) is described, which adopts cylindrical hologram diffraction grating as the calibration standard. The optical principle of the sensor is explained, and the relation between the grating motion displacement and the phase shift of interference stripes is deduced. The improvement of the integral structure and the method of photoelectric signal processing are described in detail. With the software system based on the virtual instrument development platform Labwindows/CVI and other hardwares such as the precision displacement worktable, the surfaces of typical parts are measured and the characterization results are given. The sensor has wide measuring range and high resolution, its sensitivity and resolution being independent of the wavelength of the incident light. The vertical measuring range is 0-6 mm, and the vertical resolution is 0.005μm. The experimental results show that the sensor can be used to measure and characterize the surface topography parameters of the plane and curved surface.展开更多
Flexible strain sensors play an important role in electronic skins,wearable medical devices,and advanced robots.Herein,a highly sensitive and fast response optical strain sensor with two evanescently coupled optical m...Flexible strain sensors play an important role in electronic skins,wearable medical devices,and advanced robots.Herein,a highly sensitive and fast response optical strain sensor with two evanescently coupled optical micro/nanofibers(MNFs)embedded in a polydimethylsiloxane(PDMS)film is proposed.The strain sensor exhibits a gauge factor as high as 64.5 for strain≤0.5%and a strain resolution of 0.0012%which corresponds to elongation of 120 nm on a 1 cm long device.As a proof-of-concept,highly sensitive fingertip pulse measurement is realized.The properties of fast temporal frequency response up to 30 kHz and a pressure sensitivity of 102 kPa^(−1) enable the sensor for sound detection.Such versatile sensor could be of great use in physiological signal monitoring,voice recognition and micro-displacement detection.展开更多
Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change tradi...Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with the measurement software. The laser alignment system with dual PSDs was improved on a single PSD system,and it gets higher measurement accuracy than the previous design,and it has been succeeded in designing and implement for actual shaft alignment. In the system,the range of offset measurement is ±4 mm,and the resolution is 1.5 μm,and the accuracy is less than 2 μm.展开更多
According to the principle of the magnetostriction generating mechanism, thecontrol model of giant magnetostriction material based on magnetic field and the control method withmagnetic flux density are developed. Furt...According to the principle of the magnetostriction generating mechanism, thecontrol model of giant magnetostriction material based on magnetic field and the control method withmagnetic flux density are developed. Furthermore, this control method is used to develop a giantmagnetostrictive micro-displacement actuator (GMA) and its driving system. Two control methods whosecontrol variables are current intensity and magnetic flux density are compared with each other byexperimental studies. Finally, effective methods on improving the linearity and control precision ofmicro-displacement actuator and reducing the hysteresis based on the controlling magnetic fluxdensity are obtained.展开更多
基金This project is supported by National Natural Sciences Foundation of China (No.50175037).
文摘On the basis of existing techniques, a compact micro-displacement sensor of phase grating interference (PGI) is described, which adopts cylindrical hologram diffraction grating as the calibration standard. The optical principle of the sensor is explained, and the relation between the grating motion displacement and the phase shift of interference stripes is deduced. The improvement of the integral structure and the method of photoelectric signal processing are described in detail. With the software system based on the virtual instrument development platform Labwindows/CVI and other hardwares such as the precision displacement worktable, the surfaces of typical parts are measured and the characterization results are given. The sensor has wide measuring range and high resolution, its sensitivity and resolution being independent of the wavelength of the incident light. The vertical measuring range is 0-6 mm, and the vertical resolution is 0.005μm. The experimental results show that the sensor can be used to measure and characterize the surface topography parameters of the plane and curved surface.
基金We are grateful for financial supports from the National Natural Science Foundation of China(No.61975173)the National Key Research and Development Program of China(No.SQ2019YFC170311)+3 种基金the Major Scientific Research Project of Zhejiang Lab(No.2019MC0AD01)the Key Research and Development Project of Zhejiang Province(No.2021C05003)the Quantum Joint Funds of the Natural Foundation of Shandong Province(No.ZR2020LLZ007)the CIE-Tencent Robotics X Rhino-Bird Focused Research Program(No.2020-01-006).
文摘Flexible strain sensors play an important role in electronic skins,wearable medical devices,and advanced robots.Herein,a highly sensitive and fast response optical strain sensor with two evanescently coupled optical micro/nanofibers(MNFs)embedded in a polydimethylsiloxane(PDMS)film is proposed.The strain sensor exhibits a gauge factor as high as 64.5 for strain≤0.5%and a strain resolution of 0.0012%which corresponds to elongation of 120 nm on a 1 cm long device.As a proof-of-concept,highly sensitive fingertip pulse measurement is realized.The properties of fast temporal frequency response up to 30 kHz and a pressure sensitivity of 102 kPa^(−1) enable the sensor for sound detection.Such versatile sensor could be of great use in physiological signal monitoring,voice recognition and micro-displacement detection.
基金Funded by the National Natural Science Foundation of China (60337030) .
文摘Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with the measurement software. The laser alignment system with dual PSDs was improved on a single PSD system,and it gets higher measurement accuracy than the previous design,and it has been succeeded in designing and implement for actual shaft alignment. In the system,the range of offset measurement is ±4 mm,and the resolution is 1.5 μm,and the accuracy is less than 2 μm.
基金National Natural Science Foundation of China(No.50275021)Doctoral Foundation of Education Ministry(No.2000014109)
文摘According to the principle of the magnetostriction generating mechanism, thecontrol model of giant magnetostriction material based on magnetic field and the control method withmagnetic flux density are developed. Furthermore, this control method is used to develop a giantmagnetostrictive micro-displacement actuator (GMA) and its driving system. Two control methods whosecontrol variables are current intensity and magnetic flux density are compared with each other byexperimental studies. Finally, effective methods on improving the linearity and control precision ofmicro-displacement actuator and reducing the hysteresis based on the controlling magnetic fluxdensity are obtained.