Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from ...Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from one or more sensors. Because of the problem that standard ball is deficient as a standard artifact in the coordinate unification of high-precision composite measurement in two dimensions （2D） , a new method is proposed in this paper which uses angle gauge blocks as standard artifacts to achieve coordinate unification between the image sensor and the tactile probe. By comparing the standard ball with the angle gauge block as a standard artifact, theoretical analysis and experimental results are given to prove that it is more precise and more convenient to use angle gauge blocks as standard artifacts to achieve coordinate unification of high-precision composite measurement in two dimensions.展开更多
Aiming at the shortcomings of traditional contact measurement methods such as low measurement efficiency,high cost and low accuracy,a non-contact optical measurement method based on the laser displacement sensor is pr...Aiming at the shortcomings of traditional contact measurement methods such as low measurement efficiency,high cost and low accuracy,a non-contact optical measurement method based on the laser displacement sensor is proposed.According to the relevant regulations of the coaxiality error evaluation standard and the structural characteristics of the compound gear shaft,we have designed and built a set of supporting software system as well as a hardware test platform.In this paper,the distance difference threshold and scale threshold methods are used to eliminate outlier data.The least squares circle is selected to calculate the center of the circle and the minimum containment cylinder axis method is used as the reference axis of the composite gear shaft.Compensated by the standard step shaft calibration,the coaxiality error of the composite gear shaft can be measured to be within 0.01 mm in less than two minutes.The range value of the multi-section measurement test is 0.065 mm.The average coaxiality error is∅0.476 mm.展开更多
A nano probe system which can measure precise contact force in mN scale was demonstrated. The nano probe micro parts or optical parts in nanometer range resolution and scratch was originally designed for on-machine me...A nano probe system which can measure precise contact force in mN scale was demonstrated. The nano probe micro parts or optical parts in nanometer range resolution and scratch was originally designed for on-machine measuring applications and one kind of contact type measuring probes was designed for miniaturized or microfactory system. It ideally should be of small size and able to measure surface topography in nanometer scale. A commercial capacitive displacement sensor was proposed. It was a new concept in nano probe systems which can measure the displacement of shaft driven by the variation of surface topography. The nano probe mainly consisted of three parts： a capacitive displacement sensor, a porous type air slide and a contact probe part with various tip radiuses. The porous type air slide assured the shaft slided smoothly with controllable normal force in mN scale and had high positioning accuracy. The probe part which was directly in contact with target surface, can be applied to micro/nanoscale scratching as well as the measurement of sample topography by a simple tip change.展开更多
Pressure-sensitive paint(PSP)is a global pressure measurement technique.Compared with pressure transducers,PSP has significant advantages such as high spatial resolution and a lack of contact when applied to fast-rota...Pressure-sensitive paint(PSP)is a global pressure measurement technique.Compared with pressure transducers,PSP has significant advantages such as high spatial resolution and a lack of contact when applied to fast-rotating blades.However,due to the limitations of other pressure measurement techniques,the validation of PSP measurements on fast-rotating blades is generally difficult.In this work,a comprehensive study including PSP measurement,force balance measurement,and simulation was conducted on a 1 m-diameter propeller at the China Aerodynamic Research and Development Center.First,our computational fluid dynamics(CFD)code was validated by comparing the calculated aerodynamic thrust with the results from force balance measurements.Then,the pressure distributions on the propeller blade obtained by PSP were carefully compared with the CFD results under different working conditions.The results of PSP measurements,force balance measurements,and CFD showed good agreement,and the PSP measurement errors were estimated to be less than 5% of the dynamic pressure at the blade tip.Finally,the variations in pressure distribution under different rotating speeds and free-stream velocities were discussed.展开更多
基金National Key Scientific Instrument and Equipment Development Project(No.2013YQ170539)
文摘Multi-sensor coordinate unification in dimensional metrology is used in order to get holistic, more accurate and reliable information about a workpiece based on several or multiple measurement values from one or more sensors. Because of the problem that standard ball is deficient as a standard artifact in the coordinate unification of high-precision composite measurement in two dimensions （2D） , a new method is proposed in this paper which uses angle gauge blocks as standard artifacts to achieve coordinate unification between the image sensor and the tactile probe. By comparing the standard ball with the angle gauge block as a standard artifact, theoretical analysis and experimental results are given to prove that it is more precise and more convenient to use angle gauge blocks as standard artifacts to achieve coordinate unification of high-precision composite measurement in two dimensions.
基金supported by the National Natural Science Foundation of China(No.51975293)Aeronautical Science Foundation of China (No. 2019ZD052010)
文摘Aiming at the shortcomings of traditional contact measurement methods such as low measurement efficiency,high cost and low accuracy,a non-contact optical measurement method based on the laser displacement sensor is proposed.According to the relevant regulations of the coaxiality error evaluation standard and the structural characteristics of the compound gear shaft,we have designed and built a set of supporting software system as well as a hardware test platform.In this paper,the distance difference threshold and scale threshold methods are used to eliminate outlier data.The least squares circle is selected to calculate the center of the circle and the minimum containment cylinder axis method is used as the reference axis of the composite gear shaft.Compensated by the standard step shaft calibration,the coaxiality error of the composite gear shaft can be measured to be within 0.01 mm in less than two minutes.The range value of the multi-section measurement test is 0.065 mm.The average coaxiality error is∅0.476 mm.
基金Project supported by National Core Research Center (NCRC) and Chosun University, Korea
文摘A nano probe system which can measure precise contact force in mN scale was demonstrated. The nano probe micro parts or optical parts in nanometer range resolution and scratch was originally designed for on-machine measuring applications and one kind of contact type measuring probes was designed for miniaturized or microfactory system. It ideally should be of small size and able to measure surface topography in nanometer scale. A commercial capacitive displacement sensor was proposed. It was a new concept in nano probe systems which can measure the displacement of shaft driven by the variation of surface topography. The nano probe mainly consisted of three parts： a capacitive displacement sensor, a porous type air slide and a contact probe part with various tip radiuses. The porous type air slide assured the shaft slided smoothly with controllable normal force in mN scale and had high positioning accuracy. The probe part which was directly in contact with target surface, can be applied to micro/nanoscale scratching as well as the measurement of sample topography by a simple tip change.
基金supported by the Foundation of the State Key Laboratory of Aerodynamics(Grant No.SKLA2019040302)the National Natural Science Foundation of China(Grant No.11872038).
文摘Pressure-sensitive paint(PSP)is a global pressure measurement technique.Compared with pressure transducers,PSP has significant advantages such as high spatial resolution and a lack of contact when applied to fast-rotating blades.However,due to the limitations of other pressure measurement techniques,the validation of PSP measurements on fast-rotating blades is generally difficult.In this work,a comprehensive study including PSP measurement,force balance measurement,and simulation was conducted on a 1 m-diameter propeller at the China Aerodynamic Research and Development Center.First,our computational fluid dynamics(CFD)code was validated by comparing the calculated aerodynamic thrust with the results from force balance measurements.Then,the pressure distributions on the propeller blade obtained by PSP were carefully compared with the CFD results under different working conditions.The results of PSP measurements,force balance measurements,and CFD showed good agreement,and the PSP measurement errors were estimated to be less than 5% of the dynamic pressure at the blade tip.Finally,the variations in pressure distribution under different rotating speeds and free-stream velocities were discussed.
