Nanomanufacturing of radial grating patterns by nanoimprint with a silicon mould for rotational angle measurement of micro gears

2012 ◽  
Vol 8 (1/2) ◽  
pp. 123 ◽  
Author(s):  
Syuhei Kurokawa ◽  
Morihisa Hoga ◽  
Toshiro Doi
2011 ◽  
Vol 128-129 ◽  
pp. 85-91
Author(s):  
Yi Fan Zeng ◽  
Rui Li

This paper proposes a novel method called arithmetic operations to analyze and process the generated voltage-signal from the single pair-pole magnetic encoder. Dual orthogonal voltage-signals are generated by two vertical hall sensors which are placed in the bottom of a columned magnet. When signals pass A/D converter, the quadrant determination, arithmetic operations and nonlinear correction in FPGA chip are performed before the values of rotational angle are displayed on the LED. This paper also designs and implements the single pair-pole magnetic encoder which has advantages such as high-speed, high-resolution and high-accuracy in the area of angle measurement.


Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1037 ◽  
Author(s):  
Dong Wang ◽  
Siwei Chen ◽  
Xuanpeng Li ◽  
Weigong Zhang ◽  
Haolong Jin

The measurement of the rotational angle of the wheel is critical for the smart wheel force sensor (SWFS) to obtain the wheel forces defined in the vehicle coordinates. To simplify the structure of the SWFS and overcome the shortcomings of the traditional angular transducer, a new method to evaluate the rotational speed of the wheel and then calculate the rotational angle is proposed in this paper. In this method, the centripetal acceleration caused by the rotation is recorded by three accelerometers and used carefully. What’s more, the possible sources of error are classified and analyzed. Simulations and stand experiment are carried out to demonstrate the effectiveness of the proposed method.


2014 ◽  
Vol 556-562 ◽  
pp. 3124-3128
Author(s):  
Quan Fa Yang ◽  
Gui Rong Ye ◽  
Chang You Li

A measurement method based on digital MEMS’ acceleration sensor is proposed. The paper analyzes the working principle of capacitive acceleration sensor. According to the coordinate space transformation theory, a mathematical model of the measurement method was built, and the mathematical expressions of the angle displacement of aircraft rudder was deduced; A measurement system of aircraft tail wing inclined was established using MEMS’ acceleration ADXL345, and taken STM32 as controller. Setting different angles in 3D turntable and aiming at a typical inclination angles, the aircraft tail rotation angle experiment was simulated, and experiment achieved angle measurement arranging from-90°-90°. Experiment results demonstrate that when the inclination is close to the real inclination of aircraft tail wing, the maximum error is 0.277°, less than 0.3°, which meets the requirement of measurement. For aircraft currently being used, the measurement method can achieve the angle measurement of aircraft tail wing rotating effectively.


Micromachines ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 280 ◽  
Author(s):  
Wen Wang ◽  
He Yang ◽  
Min Zhang ◽  
Zhanfeng Chen ◽  
Guang Shi ◽  
...  

Precision spherical joints are commonly employed as multiple degree-of-freedom (DOF) mechanical hinges in many engineering applications, e.g., robots and parallel manipulators. Real-time and precise measurement of the rotational angles of spherical joints is not only beneficial to the real-time and closed-loop control of mechanical transmission systems, but also is of great significance in the prediction and compensation of their motion errors. This work presents a novel approach for rotational angle measurement of spherical joints with a capacitive sensor. First, the 3-DOF angular motions of a spherical joint were analyzed. Then, the structure of the proposed capacitive sensor was presented, and the mathematical model for the rotational angles of a spherical joint and the capacitance of the capacitors was deduced. Finally, the capacitance values of the capacitors at different rotations were simulated using Ansoft Maxwell software. The simulation results show that the variation in the simulated capacitance values of the capacitors is similar to that of the theoretical values, suggesting the feasibility and effectiveness of the proposed capacitive detection method for rotational angles of spherical joints.


Author(s):  
Yongyut Kaewjumras ◽  
Jirawat Prabket ◽  
Wisut Titiroongruang ◽  
Surasak Niemcharoen

This experimental research proposes a contactless silicon-based two-dimensional (2D) Hall sensor capable of simultaneous parallel-and perpendicular-directional magnetic sensing, with a 360° angle measurement. The Hall sensor was of non-symmetrical five-ohmic contact configuration (C1 – C5). In the study, experiments were carried out in three stages. In the first-stage experiment, the current (I) and voltage (V) of the 2D Hall sensor were determined under three schemes: schemes A (C1&C2), B (C2&C5), and C (C3&C4). In the second-stage experiment, the parallel and perpendicular absolute sensitivities of the 2D sensor were examined. Considering the discrepancy between the parallel and perpendicular absolute sensitivities, signal conditioning circuitry was incorporated into the sensor system to compensate, and the rotational angles measured in the final-stage experiment. The results revealed that the I-V curves were dominantly linear, corresponding to Ohm’s law. However, the parallel and perpendicular absolute sensitivities were low and unequal. Thus, signal conditioning circuitry was incorporated into the system to address the discrepancy and improve the performance. Importantly, the 2D Hall sensor exhibited a mere ±3odiscrepancy between the measured and reference rotational angles, given the magnetic flux density of 1000 G, with the hysteresis error of 2.8%. In essence, the proposed contactless silicon-based 2D Hall sensor possesses high potential for high-precision industrial applications.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Young-Soo Park ◽  
John Arbie Agbayani ◽  
Jong-Han Lee ◽  
Jong-Jae Lee

Measuring a very small rotational angle accurately and dynamically is indeed a challenging issue, especially in the case of bridge support. Also, existing inclinometers do not have sufficient resolution and accuracy to measure a bridge’s rotational angle. In this study, a new measurement system was developed to provide a practical means for measuring dynamic rotational angle of a bridge support. It features high resolution and accuracy compared with the available systems on the market. By the combinational use of a laser pointer and a vision-based displacement measurement system, the measurement accuracy was significantly increased. The accuracy and applicability were investigated through laboratory tests. From the laboratory tests, it has been found that the developed system can be applicable to bridge support with very small rotational angle. The effectiveness of the developed system was verified through field tests on real bridges. From the full-scale implementation on two PSC girder bridges, it is observed that the proposed system can measure the rotational angle with a high accuracy and reliability.


2021 ◽  
Author(s):  
Phob Ganokroj ◽  
Nuchanun Sompornpanich ◽  
Pichitpol Kerdsomnuek ◽  
Bavornrat Vanadurongwan ◽  
Pisit Lertwanich

Abstract Background Measurement of hip rotation is a crucial clinical parameter for the identification of hip problems and the monitoring of symptoms. The objective of this study was to determine whether the use of two smartphone applications is valid and reliable for the measurement of hip rotation.Methods An experimental, cross-sectional study was undertaken to assess passive hip internal and external rotation in three positions by two examiners. The hip rotational angles were measured by a smartphone clinometer application in the sitting and prone positions, and by a smartphone compass application in the supine position; their results were compared with those of the standard, three-dimensional, motion analysis system. The validities and inter-rater and intra-rater reliabilities of the smartphone applications were evaluated.Results The study involved 24 participants. The validities were good to excellent for the internal rotation angles in all positions (ICC 0.81–0.94), good for the external rotation angles in the prone position (ICC 0.79), and fair for the sitting and supine positions (ICC 0.70–0.73). The measurement of the hip internal rotation in the supine position had the highest ICC value of 0.94 (0.91, 0.96). The two smartphone applications showed good-to-excellent intra-rater reliability, but good-to-excellent inter-rater reliability for only three of the six positions (two other positions had fair reliability, while one position demonstrated poor reliability).Conclusions The two smartphone applications have good-to-excellent validity and intra-rater reliability, but only fair-to-good inter-rater reliability for the measurement of the hip rotational angle. The most valid hip rotational position in this study was the supine IR angle measurement, while the lowest validity was the ER angle measurement in the sitting position. The smartphone application is one of the practical measurements in hip rotational angles.Trial registration: Number 20181022003 at the Thai Clinical Trials Registry (http://www. clinicaltrials.in.th) which was retrospectively registered at 2018-10-18 15:30:29. http://www.clinicaltrials.in.th/index.php?tp=utf8&task=regtrial&id=4100&menu=regtrial&smenu=trialmodify&ts=20200711091413


Sensors ◽  
2012 ◽  
Vol 12 (6) ◽  
pp. 7326-7336 ◽  
Author(s):  
Jong-Jae Lee ◽  
Hoai-Nam Ho ◽  
Jong-Han Lee

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