A Surface Normal On-Machine Measuring Method Using Eddy-Current (EC) Sensor Array

2016 ◽  
Vol 10 (6) ◽  
pp. 977-984 ◽  
Author(s):  
Meng Lian ◽  
◽  
Hai Bo Liu ◽  
Yong Qing Wang ◽  
Yang Li ◽  
...  
Keyword(s):  
Sensor Array ◽  
Measuring Method ◽  
Calculation Model ◽  
Normal Vector ◽  
Displacement Sensors ◽  
Surface Normal ◽  
Calibration Algorithm ◽  
Mirror Milling ◽  
Position Calibration ◽  
Key Aspects

Normal vector measurements of the machining point and attitude adjustments of the end effector are key aspects to meet the technological requirements of hole verticality in auto-drilling and the residual wall thickness in mirror milling. In this paper, a surface normal on-machine measuring method using an EC sensor array is proposed. The influences of the object surface inclination and the sensor array arrangement on the performance of EC displacement sensors were investigated, and the sensor measuring errors from coupling interference were effectively eliminated. Moreover, a practical calibration algorithm was established in which the positions of the EC sensors in a normal vector calculation model were accurately corrected. The feasibility of the measuring method was validated through a calibration experiment, as well as a measurement experiment based on the calibration results. The accuracy of a normal vector measurement is improved when applying the accuracy compensation and position calibration algorithm of an EC array to engineering practices.

Precise on-machine extraction of the surface normal vector using an eddy current sensor array

2016 ◽  
Vol 27 (11) ◽  
pp. 115016 ◽  
Author(s):  
Yongqing Wang ◽  
Meng Lian ◽  
Haibo Liu ◽  
Yangwei Ying ◽  
Xianjun Sheng
Keyword(s):  
Eddy Current ◽  
Sensor Array ◽  
Current Sensor ◽  
Normal Vector ◽  
Eddy Current Sensor ◽  
Surface Normal

Testing of Aspheric Surface Normal Vector Based on Phase Measuring Deflectometry

2011 ◽  
Vol 31 (6) ◽  
pp. 0612007
Author(s):  
赵文川 Zhao Wenchuan ◽  
范斌 Fan Bin ◽  
伍凡 Wu Fan ◽  
苏显渝 Su Xianyu ◽  
陈文静 Chen Wenjing
Keyword(s):  
Normal Vector ◽  
Aspheric Surface ◽  
Surface Normal

scholarly journals An Approximation Mathematical Formula of Pattern Analysis for Distorted Reflector Antennas considering Surface Normal Vector Variation

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Shuxin Zhang ◽  
Guigeng Yang ◽  
Yiqun Zhang
Keyword(s):  
Taylor Series ◽  
Phase Error ◽  
Structural Deformation ◽  
Approximation Formula ◽  
Normal Vector ◽  
Far Field ◽  
Reflector Antennas ◽  
Mathematical Formula ◽  
Surface Normal ◽  
Nodal Displacements

An approximation mathematical formula to compute the distorted radiation pattern for reflector antennas is presented. In this approximation formula, besides the phase error caused by the structural deformation being added in the far field integral, the surface normal vector variation is also taken into consideration. The formula is derived by expanding the surface normal vector into a first-order Taylor series and the phase error into a second-order Taylor series. By assembling the integrals including the contributions of both surface normal vector variation and phase error, the far field electrical vector expressed as a function of structural nodal displacements is further obtained in a matrix form. Simulation results of a distorted reflector show the application of this formula.

Error Calibration System for Time Grating Angular Displacement Sensor

2013 ◽  
Vol 662 ◽  
pp. 705-708
Author(s):  
Zhong Hua Gao
Keyword(s):  
Angular Displacement ◽  
Least Square Method ◽  
Least Square ◽  
Displacement Sensor ◽  
Calibration System ◽  
Displacement Sensors ◽  
Optical Grating ◽  
Calibration Algorithm ◽  
Error Calibration ◽  
Angular Displacements

A calibration system was developed for time grating angular displacement sensors to calibrate errors of this type of sensor. In the system, the motor was controlled by ARM processor according to the setting value coming from the USB port of the computer, and therefore the motor outputted angular displacement values. Meanwhile, with the motor turning, the optical grating, which was used as the criterion instrument, and time grating turned together corresponding angular displacements. Several displacement values from a circle of sensors of time grating and optical grating were sent to computer by serial port to be processed. Furthermore, an error calibration algorithm, which was based on the least square method (LMS), was used in this calibration system. The precise of time grating can reach to ±0.7″after calibrating using this algorithm and the process of error calibration can be automatically made by the computer.

scholarly journals Error Self-Calibration Algorithm for Acoustic Vector Sensor Array

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Peng Wang ◽  
Yujun Kong ◽  
Mingxing Zhang
Keyword(s):  
Sensor Array ◽  
Doa Estimation ◽  
Acoustic Vector Sensor ◽  
Estimation Performance ◽  
Self Calibration ◽  
Phase Errors ◽  
Vector Sensor ◽  
Calibration Algorithm ◽  
The Impact ◽  
Vector Sensor Array

In this paper, the errors of acoustic vector sensor array are classified, the impact factor of each error for the array signal model is derived, and the influence of each type of error on the direction-of-arrival (DOA) estimation performance of the array is compared by Monte Carlo experiments. Converting the directional error and location error to amplitude and phase errors, the optimization model and error self-calibration algorithm for acoustic vector sensor array are proposed. The simulation experiments and field experiment data processing of MEMS vector sensor array show that the proposed self-calibration algorithm has good parameter estimation performance and certain engineering practicability.

Sign in / Sign up

Export Citation Format

Share Document