C. Fang, Qiangxian Huang, Meng Mi, Chao-qun Wang, Lijuan Chen, Liansheng Zhang, Hongli Li
Probe tip of the Micro-coordinate Measuring Machine (Micro-CMM) is a microsphere with diameter of several hundred microns, and its sphericity is generally controlled at tens to hundreds of nanometers. Due to the small size and high precision requirement, the measurement of the microsphere morphology is difficult. In this paper, a measurement method for probe microsphere of Micro-CMM is proposed based on two SPM (Scanning Probe Microscope) probes, and a ruby microsphere of a Renishaw commercial CMM stylus is measured by the proposed method. In the experiment, the repeatability error of a maximum section profile is test, and the repeatability error is 41 nm (peak-to-peak value). Two perpendicular maximum section profiles are measured, and the corresponding diameter and roundness are estimated by the least squares method.
{"title":"A measurement method for probe microsphere of micro-CMM with double SPMs","authors":"C. Fang, Qiangxian Huang, Meng Mi, Chao-qun Wang, Lijuan Chen, Liansheng Zhang, Hongli Li","doi":"10.1117/12.2511575","DOIUrl":"https://doi.org/10.1117/12.2511575","url":null,"abstract":"Probe tip of the Micro-coordinate Measuring Machine (Micro-CMM) is a microsphere with diameter of several hundred microns, and its sphericity is generally controlled at tens to hundreds of nanometers. Due to the small size and high precision requirement, the measurement of the microsphere morphology is difficult. In this paper, a measurement method for probe microsphere of Micro-CMM is proposed based on two SPM (Scanning Probe Microscope) probes, and a ruby microsphere of a Renishaw commercial CMM stylus is measured by the proposed method. In the experiment, the repeatability error of a maximum section profile is test, and the repeatability error is 41 nm (peak-to-peak value). Two perpendicular maximum section profiles are measured, and the corresponding diameter and roundness are estimated by the least squares method.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122809421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiang Cheng, Xiaojun Liu, Changchun Chai, Hongzhou Yan, Jian Luo, Hong Zhu, H. Zhou
Currently the diode laser is widely used in the field of optoelectronics, especially in precise measurement based on laser-interferometry. Laser wavelength stability is a property that critical to the measurement. Since the laser wavelength is easy to be influenced by the environment and drive current, real-time monitoring and calibration of diode laser wavelength is extraordinary important for interferometry. In this paper, a real-time wavelength monitoring and calibration system for diode laser based interference measurement were developed. The experiment system was built and conducted to verify the feasibility of the system.
{"title":"Wavelength calibration system for diode laser","authors":"Xiang Cheng, Xiaojun Liu, Changchun Chai, Hongzhou Yan, Jian Luo, Hong Zhu, H. Zhou","doi":"10.1117/12.2512198","DOIUrl":"https://doi.org/10.1117/12.2512198","url":null,"abstract":"Currently the diode laser is widely used in the field of optoelectronics, especially in precise measurement based on laser-interferometry. Laser wavelength stability is a property that critical to the measurement. Since the laser wavelength is easy to be influenced by the environment and drive current, real-time monitoring and calibration of diode laser wavelength is extraordinary important for interferometry. In this paper, a real-time wavelength monitoring and calibration system for diode laser based interference measurement were developed. The experiment system was built and conducted to verify the feasibility of the system.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124899177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Galvanometric scanning systems are high inertial behavior and high-speed movement widely that be used in laser marking, drilling, full screen projecting and so on. Therefore, the presented galvanometric scanning system and its applications for laser projector system. In includes a galvanometric unit, motor, position detector and control circuit. All components were discussed and developed by this study. The magnetic rotor and a stator magnet are the main components of the scanner system. The moving magnet is composed of NdFeB material and the stator consists of the coil. In addition, the moving capacitive sensor is used to receive signal feedback. The driver is assembled by the high response performance OP-amplifier circuit. Finally, frequency domain methods were used to identify the scanning system.
{"title":"Design, fabrication, identification and test of a closed-loop moving magnetic scanning module for RGB laser projector","authors":"C. Chung, Chendong Lin, Ming-Fu Chen, S. Tseng","doi":"10.1117/12.2512125","DOIUrl":"https://doi.org/10.1117/12.2512125","url":null,"abstract":"Galvanometric scanning systems are high inertial behavior and high-speed movement widely that be used in laser marking, drilling, full screen projecting and so on. Therefore, the presented galvanometric scanning system and its applications for laser projector system. In includes a galvanometric unit, motor, position detector and control circuit. All components were discussed and developed by this study. The magnetic rotor and a stator magnet are the main components of the scanner system. The moving magnet is composed of NdFeB material and the stator consists of the coil. In addition, the moving capacitive sensor is used to receive signal feedback. The driver is assembled by the high response performance OP-amplifier circuit. Finally, frequency domain methods were used to identify the scanning system.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124903915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
On account of the assembling demand for the metal framework of frequency stabilizing component for laser gyro, a precision assembly system was designed and developed in this paper. The coaxiality of the metal framework and the grooved mirror is the key index to assembly. Meanwhile, the grooved mirror is fragile and the assembly force has to be monitored and controlled in real time. The installation structure of force sensor is designed and a force control unit is established. The contact force can be detected and feedback to control the movement of the linear stages to complete the displacement in the vertical direction for the operation of pick up and place parts for end effector. To reduce the time of image processing, the machine vision unit is based on high repeatability accuracy of the stage to assist image mosaic, thus the calculation workload for image mosaic is reduced, and the time of image mosaic is about 0.5s.
{"title":"Force control and visual measurement in precision assembly","authors":"Ya-wei Li, Xiao-dong Wang, Yi Luo, Shengsheng Sun","doi":"10.1117/12.2512139","DOIUrl":"https://doi.org/10.1117/12.2512139","url":null,"abstract":"On account of the assembling demand for the metal framework of frequency stabilizing component for laser gyro, a precision assembly system was designed and developed in this paper. The coaxiality of the metal framework and the grooved mirror is the key index to assembly. Meanwhile, the grooved mirror is fragile and the assembly force has to be monitored and controlled in real time. The installation structure of force sensor is designed and a force control unit is established. The contact force can be detected and feedback to control the movement of the linear stages to complete the displacement in the vertical direction for the operation of pick up and place parts for end effector. To reduce the time of image processing, the machine vision unit is based on high repeatability accuracy of the stage to assist image mosaic, thus the calculation workload for image mosaic is reduced, and the time of image mosaic is about 0.5s.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129078364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to achieve a large area of deep soil moisture monitoring, a soil moisture sensor based on fiber Bragg grating was designed. The polyimide with high water sensitivity and high linear expansion coefficient was coated to the surface of FBG. The center wavelength of the FBG will change due to moisture absorption and expansion of the polyimide material when moisture changes. Using this basis principle, the soil moisture can be measured. A stainless steel tube with a hole is used as a sensor package and wrapped in polyurethane nets to maintain consistent with the external temperature and moisture environment and prevent soil from entering the sensor. A fiber Bragg grating without a PI coating layer was packaged in the same package structure with the soil moisture sensor as a reference fiber for temperature compensation. An experimental system was set up, calibration experiments were performed on the sensors, and various performances of the sensors were tested. The experimental results show that the measuring range of moisture is 15%RH~75%RH, the sensitivity is 12.6pm/%RH, and the accuracy of the sensor is ±10.26%.
{"title":"Soil moisture sensor design based on fiber Bragg grating","authors":"Kejun Yan, Jun Liu, N. Sun, Wenting Zhong","doi":"10.1117/12.2511748","DOIUrl":"https://doi.org/10.1117/12.2511748","url":null,"abstract":"In order to achieve a large area of deep soil moisture monitoring, a soil moisture sensor based on fiber Bragg grating was designed. The polyimide with high water sensitivity and high linear expansion coefficient was coated to the surface of FBG. The center wavelength of the FBG will change due to moisture absorption and expansion of the polyimide material when moisture changes. Using this basis principle, the soil moisture can be measured. A stainless steel tube with a hole is used as a sensor package and wrapped in polyurethane nets to maintain consistent with the external temperature and moisture environment and prevent soil from entering the sensor. A fiber Bragg grating without a PI coating layer was packaged in the same package structure with the soil moisture sensor as a reference fiber for temperature compensation. An experimental system was set up, calibration experiments were performed on the sensors, and various performances of the sensors were tested. The experimental results show that the measuring range of moisture is 15%RH~75%RH, the sensitivity is 12.6pm/%RH, and the accuracy of the sensor is ±10.26%.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130195906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Zhang, Zili Zhang, Yueqiang Li, Weihu Zhou, Yan-peng He, Wei Li
3D profile measurement is widely used in many areas such as manufacturing, computer-aided design, virtual reality and medical diagnostics. As one of the core technologies in 3D profile measurement, digital fringe pattern projection is a highly sensitive noncontact technique for obtaining the 3D shape of an object. Then the grating pattern deformed by the measured object is captured by CCD cameras and decoded using appropriate algorithms so that the shape of the object can be deduced. In this paper, three sets of phase shift fringe patterns with different frequencies are projected on the surface of the measured object by a DLP projector and the deformed patterns are captured by two cameras. Then the four-step phase shift method is used to obtain the three groups of fringe patterns phases, and the three-frequency heterodyne method is adopted to unwrap the phase and obtain the absolute phase. The causes of the phase errors are analyzed and the subsequent compensation method of gamma correction of grating pattern is proposed to eliminate the main errors. Experiments are carried out and the results verify the accuracy and effectiveness of the proposed methods.
{"title":"Phase measuring method and error compensation in 3D profile measurement","authors":"Yan Zhang, Zili Zhang, Yueqiang Li, Weihu Zhou, Yan-peng He, Wei Li","doi":"10.1117/12.2512073","DOIUrl":"https://doi.org/10.1117/12.2512073","url":null,"abstract":"3D profile measurement is widely used in many areas such as manufacturing, computer-aided design, virtual reality and medical diagnostics. As one of the core technologies in 3D profile measurement, digital fringe pattern projection is a highly sensitive noncontact technique for obtaining the 3D shape of an object. Then the grating pattern deformed by the measured object is captured by CCD cameras and decoded using appropriate algorithms so that the shape of the object can be deduced. In this paper, three sets of phase shift fringe patterns with different frequencies are projected on the surface of the measured object by a DLP projector and the deformed patterns are captured by two cameras. Then the four-step phase shift method is used to obtain the three groups of fringe patterns phases, and the three-frequency heterodyne method is adopted to unwrap the phase and obtain the absolute phase. The causes of the phase errors are analyzed and the subsequent compensation method of gamma correction of grating pattern is proposed to eliminate the main errors. Experiments are carried out and the results verify the accuracy and effectiveness of the proposed methods.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127622860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Han Zhou, Bingkun Wu, Mingguang Shan, Lei Liu, Haichao Yu, Z. Zhong, Bin Liu
An extrinsic Fabry-Perot interferometric fibre microphone based on polydimethylsiloxane, or PDMS, diaphragm was proposed. The large free-standing PDMS diaphragm, with a diameter of 4 mm, is prepared by a simple “spin-strip” process. The experimental result shows that the fabricated sensor has a high dynamic pressure sensitivity of about -136 dB re 1 rad/μPa in the range of 100~2000Hz. The noise equivalent acoustic signal level of the microphone, limited by the environmental noise, is about 1000 μPa/Hz1/2. And the dynamic range is tested to be more than 47.48 dB. The proposed microphone is expected to be used in the field of weak acoustic pressure testing.
提出了一种基于聚二甲基硅氧烷(PDMS)膜片的外源法布里-珀罗干涉型光纤传声器。直径为4毫米的大型独立式PDMS膜片是通过简单的“旋带”工艺制备的。实验结果表明，该传感器在100~2000Hz范围内具有较高的动压灵敏度，约为-136 dB re 1 rad/μPa。受环境噪声限制，传声器的噪声等效声信号电平约为1000 μPa/Hz1/2。经测试，动态范围大于47.48 dB。该麦克风有望应用于弱声压测试领域。
{"title":"Optical fiber Fabry-Perot acoustic sensor based on large PDMS diaphragm","authors":"Han Zhou, Bingkun Wu, Mingguang Shan, Lei Liu, Haichao Yu, Z. Zhong, Bin Liu","doi":"10.1117/12.2511691","DOIUrl":"https://doi.org/10.1117/12.2511691","url":null,"abstract":"An extrinsic Fabry-Perot interferometric fibre microphone based on polydimethylsiloxane, or PDMS, diaphragm was proposed. The large free-standing PDMS diaphragm, with a diameter of 4 mm, is prepared by a simple “spin-strip” process. The experimental result shows that the fabricated sensor has a high dynamic pressure sensitivity of about -136 dB re 1 rad/μPa in the range of 100~2000Hz. The noise equivalent acoustic signal level of the microphone, limited by the environmental noise, is about 1000 μPa/Hz1/2. And the dynamic range is tested to be more than 47.48 dB. The proposed microphone is expected to be used in the field of weak acoustic pressure testing.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129958905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuqing Xiao, Jie Cao, Zihan Wang, Q. Hao, Haoyong Yu, Q. Luo
A novel super resolution reconstruction method is proposed to improve super resolution image performances. The proposed method uses bionic vision sampling model to obtain low resolution images and performs super resolution reconstruction in logarithmic polar coordinates. We carry out comparative experiments between the proposed method and the traditional method in terms of Peak Signal to Noise Ratio (PSNR), Structural Similarity Index Measure (SSIM) and Mean Squared Error (MSE). The results show that the performances of proposed method are better than that of the traditional method. Especially the SSIM of global image (butterfly), the proposed method is 34.45% higher than the traditional method.
{"title":"Bionic vision improves the performances of super resolution imaging","authors":"Yuqing Xiao, Jie Cao, Zihan Wang, Q. Hao, Haoyong Yu, Q. Luo","doi":"10.1117/12.2511338","DOIUrl":"https://doi.org/10.1117/12.2511338","url":null,"abstract":"A novel super resolution reconstruction method is proposed to improve super resolution image performances. The proposed method uses bionic vision sampling model to obtain low resolution images and performs super resolution reconstruction in logarithmic polar coordinates. We carry out comparative experiments between the proposed method and the traditional method in terms of Peak Signal to Noise Ratio (PSNR), Structural Similarity Index Measure (SSIM) and Mean Squared Error (MSE). The results show that the performances of proposed method are better than that of the traditional method. Especially the SSIM of global image (butterfly), the proposed method is 34.45% higher than the traditional method.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"222 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127884800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to measure the squareness of large-size workpieces, a method of squareness measurement based on laser alignment system was introduced. The structure and principle of the laser alignment system were presented. The squareness measuring method of the squareness measuring system and the laser alignment system were described respectively. This paper improved the method of squareness measurement based on laser alignment system and made the accuracy satisfied with the requirement of most in-site measurement. The experiments show that the squareness measurement accuracy of the laser alignment system can be improved to 5 μm/500 mm.
{"title":"Method of squareness measurement based on laser alignment measuring system","authors":"B. Wang, Yanhui Kang","doi":"10.1117/12.2511906","DOIUrl":"https://doi.org/10.1117/12.2511906","url":null,"abstract":"In order to measure the squareness of large-size workpieces, a method of squareness measurement based on laser alignment system was introduced. The structure and principle of the laser alignment system were presented. The squareness measuring method of the squareness measuring system and the laser alignment system were described respectively. This paper improved the method of squareness measurement based on laser alignment system and made the accuracy satisfied with the requirement of most in-site measurement. The experiments show that the squareness measurement accuracy of the laser alignment system can be improved to 5 μm/500 mm.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117207420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianning Liu, Zheng Lu, L. Ren, Mingxing Jiao, X. Bian
The refractive indexes of prisms are affected by temperature, hence the optical characteristics of triangular prisms ring cavity is disturbed enough to affect the stability of the laser gyro. Considering the temperature perturbation, the transmission matrices of the reflected and refracted beams on the prism surfaces have been modified. The modified results are the old 2×2 beam transfer matrices are corrected to new 3×3 matrices and the temperature perturbations are added. According to the self-consistent theory of the laser ring cavity, a physical model of the ring cavity light transmission with the temperature disturbance has been established. The theoretical analysis shows that when the temperature varies from -40℃ to 70℃, the changes of the optical cavity-length, frequency offset, and scale factor are 49μm, 0.011MHz and 1.96×10-10, respectively. An experimental system of the prism laser gyroscope has been established whose temperature can be changed, and the experimental results agree with the theoretical values.
{"title":"Study on temperature characteristics of triangular prisms ring cavity","authors":"Jianning Liu, Zheng Lu, L. Ren, Mingxing Jiao, X. Bian","doi":"10.1117/12.2509404","DOIUrl":"https://doi.org/10.1117/12.2509404","url":null,"abstract":"The refractive indexes of prisms are affected by temperature, hence the optical characteristics of triangular prisms ring cavity is disturbed enough to affect the stability of the laser gyro. Considering the temperature perturbation, the transmission matrices of the reflected and refracted beams on the prism surfaces have been modified. The modified results are the old 2×2 beam transfer matrices are corrected to new 3×3 matrices and the temperature perturbations are added. According to the self-consistent theory of the laser ring cavity, a physical model of the ring cavity light transmission with the temperature disturbance has been established. The theoretical analysis shows that when the temperature varies from -40℃ to 70℃, the changes of the optical cavity-length, frequency offset, and scale factor are 49μm, 0.011MHz and 1.96×10-10, respectively. An experimental system of the prism laser gyroscope has been established whose temperature can be changed, and the experimental results agree with the theoretical values.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121228653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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