Submillimeter High-Precision and High-Speed 3D Estimation Method by Two Parallel Projectors and its Application to Human Involuntary Movement Measurement

Author(s):  
Hiromu KIJIMA ◽  
Hiromasa OKU
Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 586
Author(s):  
Jincheng Liu ◽  
Jiguang Yue ◽  
Li Wang ◽  
Chenhao Wu ◽  
Feng Lyu

As the core of electronic system, the switched-mode power supply (SMPS) will lead to serious accidents and catastrophes if it suddenly fails. According to the related research, the monitoring of ripple can acquire the health degree of SMPS indirectly. To realize low-cost, high-precision, and automatic ripple measurement, this paper proposes a new ripple voltage (peak-to-peak value) measuring scheme, utilizing a DAC and two high-speed comparators. Within this scheme, the DC component of SMPS output is blocked by a high-pass filter (HPF). Then, the filtered signal and the reference voltage from a DAC together compose the input of a high-speed comparator. Finally, output pulses of the comparator are captured by a microcontroller unit (MCU), which readjusts the output of the DAC by calculation, and this process is repeated until the DAC output is exactly equal to the peak (or valley) value of ripple. Moreover, in order to accelerate the measurement process, a peak estimation method is specially designed to calculate the output ripple peak (or valley) value of buck topology through merely two measurements. Then the binary search method is utilized to obtain a more exact value on the basis of estimative results. Additionally, an analysis of the measurement error of this ripple measurement system is executed, which shows that the theoretical error is less than 0.5% where the ripple value is larger than 500 mV. Furthermore, appropriate components are selected, and a prototype is manufactured to verify the validity of the proposed theory.


2021 ◽  
pp. 002029402110022
Author(s):  
Xiaohua Zhou ◽  
Jianbin Zheng ◽  
Xiaoming Wang ◽  
Wenda Niu ◽  
Tongjian Guo

High-speed scanning is a huge challenge to the motion control of step-scanning gene sequencing stage. The stage should achieve high-precision position stability with minimal settling time for each step. The existing step-scanning scheme usually bases on fixed-step motion control, which has limited means to reduce the time cost of approaching the desired position and keeping high-precision position stability. In this work, we focus on shortening the settling time of stepping motion and propose a novel variable step control method to increase the scanning speed of gene sequencing stage. Specifically, the variable step control stabilizes the stage at any position in a steady-state interval rather than the desired position on each step, so that reduces the settling time. The resulting step-length error is compensated in the next acceleration and deceleration process of stepping to avoid the accumulation of errors. We explicitly described the working process of the step-scanning gene sequencer and designed the PID control structure used in the variable step control for the gene sequencing stage. The simulation was performed to check the performance and stability of the variable step control. Under the conditions of the variable step control where the IMA6000 gene sequencer prototype was evaluated extensively. The experimental results show that the real gene sequencer can step 1.54 mm in 50 ms period, and maintain a high-precision stable state less than 30 nm standard deviation in the following 10 ms period. The proposed method performs well on the gene sequencing stage.


Author(s):  
Tingting Yin ◽  
Zhong Yang ◽  
Youlong Wu ◽  
Fangxiu Jia

The high-precision roll attitude estimation of the decoupled canards relative to the projectile body based on the bipolar hall-effect sensors is proposed. Firstly, the basis engineering positioning method based on the edge detection is introduced. Secondly, the simplified dynamic relative roll model is established where the feature parameters are identified by fuzzy algorithms, while the high-precision real-time relative roll attitude estimation algorithm is proposed. Finally, the trajectory simulations and grounded experiments have been conducted to evaluate the advantages of the proposed method. The positioning error is compared with the engineering solution method, and it is proved that the proposed estimation method has the advantages of the high accuracy and good real-time performance.


Cytotherapy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. S97
Author(s):  
J. Bell ◽  
Y. Huang ◽  
S. Yung ◽  
H. Qazi ◽  
C. Hernandez ◽  
...  

Author(s):  
S. Tiguntsev

In classical physics, time is considered absolute. It is believed that all processes, regardless of their complexity, do not affect the flow of time The theory of relativity determines that the flow of time for bodies depends both on the speed of movement of bodies and on the magnitude of the gravitational potential. It is believed that time in space orbit passes slower due to the high speed of the spacecraft, and faster due to the lower gravitational potential than on the surface of the Earth. Currently, the dependence of time on the magnitude of the gravitational potential and velocity (relativistic effect) is taken into account in global positioning systems. However, studying the relativistic effect, scientists have made a wrong interpretation of the difference between the clock frequency of an orbiting satellite and the clock frequency on the Earth's surface. All further studies to explain the relativistic effect were carried out according to a similar scenario, that is, only the difference in clock frequencies under conditions of different gravitational potentials was investigated. While conducting theoretical research, I found that the frequency of the signal changes along the way from the satellite to the receiver due to the influence of Earth's gravity. It was found that the readings of two high-precision clocks located at different heights will not differ after any period of time, that is, it is shown that the flow of time does not depend on the gravitational potential. It is proposed to conduct full-scale experiments, during which some high-precision clocks are sent aboard the space station, while others remain in the laboratory on the surface of the earth. It is expected that the readings of the satellite clock will be absolutely identical to the readings of the clock in the Earth laboratory.


Sign in / Sign up

Export Citation Format

Share Document