scholarly journals An Innovative Dual-Axis Precision Level Based on Light Transmission and Refraction for Angle Measurement

2020 ◽  
Vol 10 (17) ◽  
pp. 6019
Author(s):  
Yubin Huang ◽  
Yuchao Fan ◽  
Zhifeng Lou ◽  
Kuang-Chao Fan ◽  
Wei Sun
Keyword(s):  
Measurement Accuracy ◽  
Light Transmission ◽  
Measurement Range ◽  
High Accuracy ◽  
Angle Measurement ◽  
Light Refraction ◽  
Transmission Design ◽  
Precision Level ◽  
True Signal ◽  
Better Than

Currently, the widely used pendulum-type precision level cannot be miniaturized because reducing the size of the pendulum will reduce its displacement so as to decrease the measurement accuracy and resolution. Moreover, the commercial pendulum-type level can only sense one direction. In this paper, an innovative compact and high-accuracy dual-axis precision level is proposed. Based on the optical principle of light refraction and the reference of the invariant liquid level, the pendulum is no more needed. In addition, based on the light transmission design, there is no reflection signal to interfere with the true signal. Therefore, the level can achieve a high accuracy and small-sized design. The calibration result shows the error of the proposed precision level is better than ±0.6 arc-sec in the measurement range of ±100 arc-sec, and better than ±5 arc-sec in the full measurement range of ±800 arc-sec.

Study on the Angle Measurement of Laser Shaft Alignment Instrument

2014 ◽  
Vol 898 ◽  
pp. 644-647
Author(s):  
Yao Lang ◽  
Dan Zheng ◽  
Xiu Yan Lv
Keyword(s):  
Measurement Accuracy ◽  
Measurement Data ◽  
Vertical Plane ◽  
Measurement Range ◽  
Angle Measurement ◽  
Measurement Point ◽  
Shaft Alignment ◽  
Conversion Formula

Laser shaft alignment instrument needs to know the angle which is rotated by the axis of measurement point at each time. It adopted the accelerometer ADXL203 to measure angle and put its two sensing axis in the vertical plane, and then calculated its outputs. It makes the conversion formula of inclination and acceleration better to improve the measurement accuracy, and the measurement range achieves 360 °. Finally, the measurement data dealt with mathematics are displayed by LabVIEW, and it friendly achieves the man-machine interactive function.

An Ultra-Precision Air-Pin Sensor and Its Dynamic Characteristics

2005 ◽  
Vol 295-296 ◽  
pp. 557-562
Author(s):  
Hui Zhang ◽  
S.X. Deng ◽  
Hui Qiang Wang ◽  
S. Chen
Keyword(s):  
Response Time ◽  
Measurement Technique ◽  
Dynamic Characteristics ◽  
Measurement Accuracy ◽  
Measurement Range ◽  
Electronic Sensor ◽  
Dimension Measurement ◽  
Ultra Precision ◽  
New Type ◽  
Better Than

The non-contact pneumatic measurement technique is useful for dimension measurement. The authors have developed a new type of air-pin pneumatic-electronic sensor. The ultra-precision air-pin sensor and the dynamic characteristics of the sensor are investigated. The measurement accuracy of the air-pin pneumatic-electronic sensor is better than 0.1µm for the 10µm measurement range. The response time is less then 10ms.

A Filtering Control Method of the Gimbal Rate-Servo System in DGMSCMG Based on Strong Tracking Filter

2014 ◽  
Vol 875-877 ◽  
pp. 2164-2169
Author(s):  
Xiao Cen Chen ◽  
Mao Yin Chen
Keyword(s):  
Signal Processing ◽  
Measurement Accuracy ◽  
Control Method ◽  
Servo System ◽  
High Accuracy ◽  
Angle Measurement ◽  
Parameter Change ◽  
Simulation Results ◽  
Strong Tracking Filter ◽  
Tracking Filter

This paper proposes a filtering control method of the gimbal rate-servo system in DGMSCMG based on strong tracking filter. Due to the low angle measurement accuracy of the angle measurement device, this signal processing technology can overcome the shortcoming as well as improve the robustness of the controlled plant to the environment disturbance and parameter change. Meanwhile, high accuracy of modeling is not required owing to the advantage of the strong tracking filter. The simulation results verify the effectiveness of the method.

A Design of High-Accuracy Displacement Measurement Instrument from Principles of Optics

2012 ◽  
Vol 170-173 ◽  
pp. 2924-2928
Author(s):  
Sheng Biao Chen ◽  
Yun Zhi Tan
Keyword(s):  
Measurement Instrument ◽  
High Accuracy ◽  
Mechanical Tests ◽  
Total Reflection ◽  
Displacement Measurement ◽  
New Method ◽  
Water Volume ◽  
Water Drainage ◽  
Accuracy Of Measurement ◽  
Better Than

In order to measure the water drainage volume in soil mechanical tests accurately, it develop a new method which is based on principles of optics. And from both physical and mathematic aspects, it deduces the mathematic relationship between micro change in displacement and the increment projected on screen. The result shows that total reflection condition is better than refraction condition. What’s more, the screen could show the water volume micro variation clearly, so it can improve the accuracy of measurement.

scholarly journals Temperature Prediction of PMSMs Using Pseudo-Siamese Nested LSTM

2021 ◽  
Vol 12 (2) ◽  
pp. 57
Author(s):  
Yongping Cai ◽  
Yuefeng Cen ◽  
Gang Cen ◽  
Xiaomin Yao ◽  
Cheng Zhao ◽  
...  
Keyword(s):  
Electric Vehicles ◽  
Simple Structure ◽  
High Accuracy ◽  
Stator Winding ◽  
High Power Density ◽  
Temperature Prediction ◽  
Permanent Magnet Synchronous Motors ◽  
Training Performance ◽  
Synchronous Motors ◽  
Better Than

Permanent Magnet Synchronous Motors (PMSMs) are widely used in electric vehicles due to their simple structure, small size, and high power-density. The research on the temperature monitoring of the PMSMs, which is one of the critical technologies to ensure the operation of PMSMs, has been the focus. A Pseudo-Siamese Nested LSTM (PSNLSTM) model is proposed to predict the temperature of the PMSMs. It takes the features closely related to the temperature of PMSMs as input and realizes the temperature prediction of stator yoke, stator tooth, and stator winding. An optimization algorithm of learning rate combined with gradual warmup and decay is proposed to accelerate the convergence during the training and improve the training performance of the model. Experimental results reveal the proposed method and Nested LSTM (NLSTM) achieves high accuracy by comparing with other intelligent prediction methods. Moreover, the proposed method is slightly better than NLSTM in temperature prediction of PMSMS.

scholarly journals Modifying Kinect placement to improve upper limb joint angle measurement accuracy

2016 ◽  
Vol 29 (4) ◽  
pp. 465-473 ◽  
Author(s):  
Na Jin Seo ◽  
Mojtaba F. Fathi ◽  
Pilwon Hur ◽  
Vincent Crocher
Keyword(s):  
Upper Limb ◽  
Measurement Accuracy ◽  
Joint Angle ◽  
Angle Measurement

scholarly journals Effectiveness of Variable-Gain Kalman Filter Based on Angle Error Calculated from Acceleration Signals in Lower Limb Angle Measurement with Inertial Sensors

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Yuta Teruyama ◽  
Takashi Watanabe
Keyword(s):  
Kalman Filter ◽  
Lower Limb ◽  
Measurement Accuracy ◽  
Inertial Sensors ◽  
Angle Measurement ◽  
Angle Error ◽  
Variable Gain ◽  
Improve Measurement ◽  
Kalman Gain ◽  
Acceleration Signals

The wearable sensor system developed by our group, which measured lower limb angles using Kalman-filtering-based method, was suggested to be useful in evaluation of gait function for rehabilitation support. However, it was expected to reduce variations of measurement errors. In this paper, a variable-Kalman-gain method based on angle error that was calculated from acceleration signals was proposed to improve measurement accuracy. The proposed method was tested comparing to fixed-gain Kalman filter and a variable-Kalman-gain method that was based on acceleration magnitude used in previous studies. First, in angle measurement in treadmill walking, the proposed method measured lower limb angles with the highest measurement accuracy and improved significantly foot inclination angle measurement, while it improved slightly shank and thigh inclination angles. The variable-gain method based on acceleration magnitude was not effective for our Kalman filter system. Then, in angle measurement of a rigid body model, it was shown that the proposed method had measurement accuracy similar to or higher than results seen in other studies that used markers of camera-based motion measurement system fixing on a rigid plate together with a sensor or on the sensor directly. The proposed method was found to be effective in angle measurement with inertial sensors.

scholarly journals RESEARCH ON THE ACCURACY OF ANGLE MEASUREMENT / KAMPŲ MATAVIMO TIKSLUMO TYRIMAS

2012 ◽  
Vol 3 (6) ◽  
pp. 15-18 ◽  
Author(s):  
Artūras Prielaidas ◽  
Rimas Lazdinas
Keyword(s):  
Main Part ◽  
Measurement Accuracy ◽  
Angle Measurement ◽  
Rotary Disk

Rotary encoders are the main devices in industrial angle measurement. Accuracy is very important and is assured by the technology of manufacture. The main part (rotary disk) is under examination, and therefore a number of its characteristics are established and a comparison with the assembled encoder is presented. In conclusion, an error in the angle of the rotary disk makes a possibility of forecasting an error in the assembled encoder angle. Santrauka Nagrinėjamas limbų paklaidų matavimas, jų vertinimas, fotoelektrinių matavimų keitiklių paklaidų matavimas, bandoma nustatyti keitiklio paklaidų priklausomybę nuo limbo paklaidų. Pateikta limbų, keitiklių apžvalga, analizė, pagrindinės schemos. Atlikta limbų ir keitiklių paklaidų aproksimacija parametrinėmis funkcijomis. Apibendrinti visų matavimų rezultatai – kas būdinga paklaidų kreivėms, kokie dydžiai, jų aproksimacijos parametrinėmis funkcijomis rezultatai, formulės, analizė. Atlikti koreliacijos tarp limbo ir matavimo keitiklio paklaidų tyrimai.

scholarly journals A Novel Vision-Based Pose Measurement Method Considering the Refraction of Light

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4348 ◽  
Author(s):  
Wei Liu ◽  
Xin Ma ◽  
Xiao Li ◽  
Yi Pan ◽  
Fuji Wang ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
High Speed ◽  
Measurement Accuracy ◽  
Performance Testing ◽  
Angle Measurement ◽  
Normal Vector ◽  
Calibration Model ◽  
Linear Calibration ◽  
Observation Window ◽  
Vision Measurement

Nowadays, due to the advantages of non-contact and high-speed, vision-based pose measurements have been widely used for aircraft performance testing in a wind tunnel. However, usually glass ports are used to protect cameras against the high-speed airflow influence, which will lead to a big measurement error. In this paper, to further improve the vision-based pose measurement accuracy, an imaging model which considers the refraction light of the observation window was proposed. In this method, a nonlinear camera calibration model considering the refraction brought by the wind tunnel observation window, was established first. What’s more, a new method for the linear calibration of the normal vector of the glass observation window was presented. Then, combining with the proposed matching method based on coplanarity constraint, the six pose parameters of the falling target could be calculated. Finally, the experimental setup was established to conduct the pose measurement study in the laboratory, and the results satisfied the application requirements. Besides, experiments for verifying the vision measurement accuracy were also performed, and the results indicated that the displacement and angle measurement accuracy approximately increased by 57% and 33.6%, respectively, which showed the high accuracy of the proposed method.

scholarly journals High-Accuracy Calibration Based on Linearity Adjustment for Eddy Current Displacement Sensor

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2842 ◽  
Author(s):  
Wei Liu ◽  
Bing Liang ◽  
Zhenyuan Jia ◽  
Di Feng ◽  
Xintong Jiang ◽  
...  
Keyword(s):  
Eddy Current ◽  
Measurement Accuracy ◽  
Characteristic Curve ◽  
Calibration Method ◽  
High Accuracy ◽  
Output Characteristic ◽  
Displacement Sensor ◽  
Support Vector ◽  
Displacement Sensors ◽  
Calibration Accuracy

High precision position control is essential in the process of parts manufacturing and assembling, where eddy current displacement sensors (ECDSs) are widely used owing to the advantages of non-contact sensing, compact volume, and resistance to harsh conditions. To solve the nonlinear characteristics of the sensors, a high-accuracy calibration method based on linearity adjustment is proposed for ECDSs in this paper, which markedly improves the calibration accuracy and then the measurement accuracy. After matching the displacement value and the output voltage of the sensors, firstly, the sensitivity is adjusted according to the specified output range. Then, the weighted support vector adjustment models with the optimal weight of the zero-scale, mid-scale and full-scale are established respectively to cyclically adjust the linearity of the output characteristic curve. Finally, the final linearity adjustment model is obtained, and both the calibration accuracy and precision are verified by the established calibration system. Experimental results show that the linearity of the output characteristic curve of ECDS adjusted by the calibration method reaches over 99.9%, increasing by 1.9–5.0% more than the one of the original. In addition, the measurement accuracy improves from 11–25 μ m to 1–10 μ m in the range of 6mm, which provides a reliable guarantee for high accuracy displacement measurement.

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