High-precision System Research Articles

О проектных работах при создании опорных геодезических сетей с использованием ГИС-технологий

During the last decades Geodesy and other Earth Sciences have undergone revolutionary changes concerning the use of Global Positioning Systems. Currently, traditional geodetic and topographic technologies are giving way to high-precision, productive and all-weather space systems. In 1995 the Federal Service of Geodesy and Cartography approved “the Concept of transiting topographic and geodetic production to autonomous methods of satellite coordinate definitions”. The transition to new technologies entails restructuring not only the methods of determining the coordinates, but also the stages of pre-design and design work. Currently, there has been intensive penetration of geoinformation technologies into sciences related to the analysis and processing spatially coordinated data, and geodetic data in particular. Specialized software products are developed but they are quite expensive and difficult for mastering. The authors describe the opportunities of using standard geographic information systems (for example, GIS ArcView V. 3.1) in the view of their spatial orientation for the analysis and optimal selection of the points of the initial geodetic framework and effective implementation of the complex of geodetic works, in order to accurately determine the coordinates of the points of the created geodetic reference network.

A Portable Online Current Monitoring System with High Precision

The monitoring of current is great significance to evaluate the running state of electrical equipments. In this paper, a portable high-precision online current detection system is presented, and a current sensor is designed which can be opened-closed conveniently. The current sensors have the same frame structure and size, but the number of turns is different. Coils with fewer turns are used to measure the large current, and coils with more turns are used to measure the weak current. By the cooperation of two coils, the accurate measurement of current in a large dynamic range can be achieved and has the advantages of easy installation and small size. In order to improve the accuracy, an improved digital integration algorithm is proposed. The results show that the error of the system is not more than 0.7% when the current ranges from 0 to 1 A, and the error is not more than 0.21% when the current is between 1 and 100 A.

High-precision synchronization detection method for bistatic radar.

To improve the accuracy of radar ranging and positioning under complex backgrounds, a high-precision synchronization detection method for bistatic radar is proposed based on different-frequency phase processing. First, the transmit signal and receive signal are converted to radio frequency pulses by frequency conversion. Then, the transmit signal is roughly measured with a field-programmable gate array. The obtained rough signal is used as the reference signal under the control of the direct digital synthesizer frequency synthesizer. Second, the transmit signal and receive signal are each synchronized with the reference signal in a different-frequency phase detection. These detection results are used as the starting signal and stopping signal of the counter gate. Finally, all the signals are counted, and the time synchronization between the transmit signal and the receive signal is implemented by processing the counting value. The experimental results show that a time synchronization precision of 1.5 ps and a frequency stability of 6.2 × 10-13/s can be reached. This method has the advantages of a fast time response, good noise suppression, and high measurement precision and strong system reliability.

Correction: Shen, T. et al. High-Precision and Low-Cost Wireless 16-Channel Measurement System for Malachite Green Detection. Micromachines, 2018, 9, 646.

In the published paper [...].

Application of SoPC in High-precision Geoelectric Data Acquisition System

SoPC technology based on FPGA is a flexible and efficient countermeasure for system-on-chip, which provides a new way to develop high-precision geoelectric data acquisition devices. This paper introduces the application of SoPC technology to research and design of an A/D conversion controller which complies with the time sequence of CS5372, a module converting the serial data to parallel one. a resampling FIR digital filter using Matlab and DSP Bulider, a NIOS II Soft IP Core integrated by Quartus II and a PC software designed with LabVIEW. Under the application of equipments mentioned above, Cyclone chip, which replaces expensive CS5376, can be used to realize the acquisition of the high-precision geoelectric data. As the result shown, the use of the technology of SoPC can greatly improve the cost-effectiveness of high-precision geoelectric data acquisition devices and also can integrate the digital parts of geoelectric data acquisition devices into a chip, which also provide an effective way to solve problems under the complex geoelectric conditions.

Two-Dimensional Code-Based Indoor Positioning System With Feature Graphics

Owing to different positioning methods in indoor locations that require base stations, the positioning accuracy cannot be guaranteed, and the cost of reconstructing the base station becomes high. In this paper, a positioning method based on a two-dimensional code with feature graphs using the advantage of scale-invariant feature transform (SIFT) is proposed, where the reconstruction cost of the scene is minimized, and the SIFT matching accuracy is improved with iteration of the transformation matrix. The experimental results demonstrated the positioning error is within 1.2 cm for a room with the dimension of 7 m × 6 m × 2.8 m. Compared with the previously published results under the similar conditions, our proposed scheme has the advantage of low-cost and high-precision system.

Efficient multi‐parameter calibration method for CVC assist robot with servo‐navigation system

High precision and servo-puncture navigation system is of great significance for the clinical application of central venous catheter (CVC) puncture-assist robot guided by ultrasound. Therefore, the authors proposed a new servo-predictive navigation system, which can track the posture of robot and predict the puncturing needle path in real time, effectively solving the limitation of conventional path plan line, such as path plan line deviation. For ensuring the accuracy of this predictive navigation system, a multi-parameter calibration method using particle swarm optimisation (PSO) based on self-adaptive system was adopted in this research, and applied to authors’ self-developed servo-predictive navigation system for puncture-assist robot MRAPS II. Experimental results indicated that by calibrating mechanical and control parameters, the authors can effectively improve the accuracy of servo-navigation system. It greatly promoted the use of CVC puncture-assist robot in clinical application.

Nanoscale displacement measurement

Research in the field of nanotechnology requires high accuracy and reliability of the obtained results, i.e., an appropriate metrological support of instruments and equipment is needed, which is used in the measurement of linear dimensions, movements, speeds and accelerations of nano-objects. These high-precision systems and instruments need special methods and means of verification/calibration. For measuring linear displacements in the nano-range, non-destructive optical methods of laser interferometry and phasemetery are most promising, providing high sensitivity ~ 10-9 m to the object displacement, high locality, absolute calibration character of measurements in portions of the laser wavelength, and the ability to automate the obtaining and processing of measuring information. In this work, a study of actuator characteristics depending on the applied voltage is considered. The developed 'interferometerphase meter' measuring system allows online investigating of complex piezoceramic structures used in various devices as actuators and the study of object characteristics under the different influences: pulsed and harmonic forms of applied voltage.

基于二维振镜与位置灵敏探测器的高精度激光跟踪系统

基于二维振镜与位置灵敏探测器的高精度激光跟踪系统

Precise Doppler shift measurement method based on motion radiation sources

Motion radiation sources, especially space motion radiation sources such as satellite, missile and aircraft and so on, have the Doppler shift relative to the ground detection equipment. A real-time and accurate localization of motion targets can be achieved using the Doppler shift. To reduce the noise and improve the positioning accuracy of motion targets under complex backgrounds, a precise Doppler shift measurement method is proposed based on motion radiation sources. Using frequency tracking and synthesis techniques, the captured signals of the motion radiation sources are converted into radio frequency signals as the measured signal, and by coarse measurement method, the traditional pulse counting method, the frequency nominal value of the measured signal can be obtained, and will be used as the frequency standard signal comparing pulse phase with the measured signal. The precise Doppler shift measurement of the measured signal is implemented using a high-resolution different-frequency group quantization phase processing. The experimental results indicate that the frequency stability of the system reaches the 4.3E−12/s level. Compared to the traditional Doppler shift measurement method, it has the advantages of a low cost, fast response, good noise suppression, high measurement precision and strong system reliability. This method has an important application in radio detection and ranging, location, tracking, early warning and surveillance of space motion targets, weapon control and navigation positioning and other high-tech fields.

СИНТЕЗ СВЕРТОЧНЫХ ФУНКЦИЙ В РЕАЛЬНОМ ВРЕМЕНИ В СИСТЕМАХ ПРОГРАММНО-ЗАВИСИМОГО РАДИО И ФАЗО-ЧАСТОТНЫХ ИЗМЕРИТЕЛЬНЫХ УСТРОЙСТВАХ

This article presents a state-of-the-art method of mathematical analysis and implementation of a hardware-accelerated generator of kernel functions based on Morlet wavelet. The method is based on heavy usage of hardware cores of high-performance programmable logic devices (PLD) for generating harmonic and Gaussian modulating functions in real-time mode. The usage of modulated harmonic series allows tuning parameters of kernel functions both in frequency and time domains, while fine tuning of damping factor of Gaussian function is performed on the base of fixed-point representation of wavelet samples. The proposed hardware generator has a feature allowing to create high-order kernel functions, which is impossible with the approach based on storing coefficients in on-chip memory limited in size. An analysis performed in the article allows calculating a set of integration limits and corresponding damping coefficients for Gaussian modulating function. Implementation on the PLD was performed with combination of existing IP-cores based on CORDIC algorithm and original developed components. Modelling and implementation are performed with Kintex-7 series PLD. Using this approach several high-precision systems were designed. These systems are precision measurement devices for frequency and phase measurements. They also may be used for software-defined radio devices, including pure digital implementation of an input radio-frequency signal. Some examples are also reviewed.

High-Precision and Low-Cost Wireless 16-Channel Measurement System for Malachite Green Detection.

Focusing on the issue of the malachite green traditional test methods such as large volume, high cost and high complex, this paper proposed a novel multi-channel electrochemical malachite green detection system. Specific recognition properties of malachite green DNA adapter is employed to realize accurate sensing of concentration of malachite green, which can achieve precise detection of malachite green concentration with low noise and high precision. The maximum measurement capability of multi-channel acquisition system is 16 samples in a batch. According to the experimental results, malachite green could be detected quantitatively in the range from 10−3 μg/mL to 10 μg/mL, which performs well in the test of malachite green residues in aquatic product transportation.

Single Cylinder-Type Piezoelectric Actuator with Two Active Kinematic Pairs

There is an ever-increasing demand for small-size, low-cost, and high-precision positioning systems. Therefore, investigation in this field is performed to search for various solutions that can meet technical requirements of precise multi-degree-of-freedom (DOF) positioning systems. This paper presents a new design of a piezoelectric cylindrical actuator with two active kinematic pairs. This means that a single actuator is used to create vibrations that are transformed into the rotation of the sphere located on the top of the cylinder and at the same time ensure movement of the piezoelectric cylinder on the plane. Numerical and experimental investigations of the piezoelectric cylinder have been performed. A mathematical model of contacting force control was developed to solve the problem of positioning of the rotor when it needs to be rotated or moved according to a specific motion trajectory. The numerical simulation included harmonic response analysis of the actuator to analyze the trajectories of the contact points motion. A prototype actuator has been manufactured and tested. Obtained results confirmed that such a device is suitable for both positioning and movement of the actuator in the plane.

Alignment turning system for precision lens cells

This research increases the ability and value of a traditional vertical lathe and applies to manufacture a precise lens cell for the optical industry. The optical performance is limited by the residual centration error and position accuracy of conventional assembly methods. Recently, the development of a poker-chip assembly system with high-precision lens barrels has overcome these limitations and provided a solution for ultra-high-performance optical systems. To develop a high-precision lens cell by using poker-chip assembly, an alignment turning system (ATS), is developed based on a vertical lathe and equipped with tactile and optical measurement modules. Inside the ATS, the building-in the vibration/temperature monitoring sensors, which help to self-monitoring and network communication with the intelligent manufacturing techniques, to understand and master the reliability and efficiency of ATS. This system can manufacture precise lens cells, applied for optical metrology, high numerical aperture objective lenses, and lithography projection lenses. This paper describes the design and development of the ATS and its capabilities. The ATS is composed of measurement, alignment, and turning modules. After the ATS completes the measurement, alignment, and turning processes, the centration error of a lens cell, which is 200 mm in diameter, can be controlled to within 10 arcsec. Here, a lens cell with three subcells was assembled through the poker-chip method; each subcell was measured and then it underwent alignment and turning processes. The lens assembly test was performed five times by three technicians, and the average transmission centration error of the assembly lens was 12.45 arcsec. The results demonstrate that the ATS can achieve considerable assembly efficiency for high-precision optical systems.

Study of travel time variability using two-wheeler probe data – an Indian experience

The objective of this study is to examine travel time reliability under the heterogeneous traffic conditions prevailing in developing countries such as India. The study is carried out using a motorised two-wheeler, which is a dominant vehicular type in conditions such as are found in India on urban arterial roads. Eight runs are conducted during morning peak hours by driving a motorised two-wheeler mounted with a performance box (equipped with high-precision global positioning system) with the traffic stream on the test route between Athwa and Piplod, in Surat city, Gujarat, situated in the western part of India. One of the major outcomes of the study is to propose the most suitable relationships between buffer time index (BTI) and volume-demand-to-capacity (V/C) ratio, as well as between planning time index (PTI) and V/C ratio. From the results, it is found that a polynomial function-based model can predict BTI as well as PTI for the given V/C ratio more accurately. The study also highlights the development of a methodology to define the level of service of a roadway facility based on travel time reliability measures. Furthermore, this research work discusses potential reliability measures for capturing travel time variations more appropriately.

COMPLEXING INFORMATION FROM DIFFERENT SOURCES IN THE ON-BOARD SYSTEMS SEARCH AND RESCUE OPERATIONS

One of the urgent problems civil and military aviation is providing information support to the crew. Control of the surface below and warnings of dangerous situations and objects are required. This problem is most acute in reduced visibility conditions due to low light conditions, heavy precipitation, fog, smoke or dust. Therefore, the developers of avionics seek to create systems that enable all-weather monitoring of the surrounding space. To solve this problem, modern aircraft on-Board survey systems are equipped with image sensors, both passive and active, working in different spectral ranges. In addition, the use of modern high-precision navigation systems and digital computing technology makes it possible to integrate information about the surface below from multispectral sensors with a priori geospatial data concentrated in digital maps.

Late Quaternary tectonic activity and shortening rate of the Beiluntai fault zone in the South Tianshan, Xinjiang, NW China

The Beiluntai fault is a Holocene active fault and is the boundary fault between the South Tianshan and Tarim Basin. Since the Late Quaternary, the continuous activities of the Beiluntai fault have caused dislocation, deformation, and fold uplift of multi-phase alluvial geomorphologic surfaces. Using a high-precision differential global positioning system, we measured the fault scarp morphology of multi-phase geomorphologic surfaces in the Akeaiken and Zhuanchang sections of the Beiluntai fault. Via large-scale active fault mapping, we found that the Akeaiken section is dominated by thrusting, while the Zhuanchang section is dominated by fold uplift. We obtained the ages of the different phases of the geomorphologic surfaces (Fan4, Fan3b, Fan3c, and Fan2) using the optically stimulated luminescence dating method. We found that since the formation of the Fan4 geomorphologic surface, the crustal shortening rate (approximately 2.4 mm/a) of the Akeaiken section has remained basically constant. However, the crustal shortening rate of the Zhuanchang section in the south–north direction (1.43–1.81 mm/a) during the Late Quaternary was significantly less than that in the Akeaiken section, suggesting that the crustal shortening rate in the south–north direction of the Beiluntai fault zone decreases from west to east. A comprehensive comparison of the South Tianshan piedmont thrust-and-fold belt system also showed that the crustal shortening rate decreases from west to east.

Micro-thrust high-precision satellite formation system based on Cartwheel configuration

Micro-thrust high-precision satellite formation system based on Cartwheel configuration

Corn seeding process fault cause analysis based on a theoretical and experimental approach

Contemporary trends have set the need for high precision systems in agricultural operations, but it is the seeding technology in the first place that must satisfy the toughest demands to achieve the highest possible profit. The improvement of seeding precision is impossible without knowledge of the working principles of all parts of a singulation mechanism and all factors which influence the seeding errors. The evolution of a seeder depended crucially on the improvement of the testing methodology and techniques. This paper presents a photo-electronic device which monitors the seed flow at free fall after leaving the seeding mechanism. An air blowing seeding mechanism was used to simulate the seeding. Its performances were tested with seven varieties of corn seed, two seeding plates, two different air flow rates, and four different speeds of revolution of the seeding plate. A full factorial design was used to determine the significance of influence of four input factors and interactions of two of them. Data validation was done by comparing the values calculated according to visual analysis of high-speed camera recordings and photo-electronic system data where a strong relationship was achieved (R2 > 0.99). It was determined that the speed of revolution of the seeding plate had the greatest influence on the varying distance between the consecutive seeds, while the seed variety exerted the least influence. The pressure of air flow and the variety of the seeds had the most significant influence on the variation of quality of feed index, although, the type and speed of revolution of the seeding plate were also statistically significant parameters. The occurrence of miss and multiple seed were caused by air flow pressure, variety of the seeds, type of the seeding plate, i.e., speed of revolution of the seeding plate. The applied optimization method can be a useful tool for finding the best possible combination of input parameters observed in the test in order to fulfill the criteria which vary depending on the user’s needs.

PRIMARY TESTING OF AUTOMATED DUAL-AXIS SOLAR TRACKER IN THE CLIMATIC CONDITIONS OF THE ORENBURG REGION AS THE PROSPECTS FOR THE ESTABLISHMENT OF A HARDWARE-SOFTWARE COMPLEX

One of the reasons for the high cost of electricity generated by statically located solar power plants is the low efficiency of photoelectric converters. Using high-precision solar tracking system will solve this problem. The paper provides a detailed description of the developed modernized structure of an autonomous solar power station with statically and dynamically located modules of solar batteries and a physical model of an automated dual-axis solar tracker. The presented development allows us to increase energy efficiency of solar batteries by precision pointing dynamically located solar modules on the Sun in two coordinates (azimuth and declination angle) during the day. In addition, it is shown that another feature of this photovoltaic system is that statically and dynamically located photoelectric modules are equipped with two types of solar cells – monocrystalline and polycrystalline that leads to an additional gain in the generation of electrical power regardless of the clouds. The ways of increasing the reliability of the autonomous solar power plant operation are mentioned. We have considered the solar tracking systems in the Russian Federation (Orenburg, Tomsk, Chelyabinsk regions) and abroad (United States of America, India, Iran, Turkey, Taiwan), and have justified the necessity of using photovoltaic systems with solar trackers. Moreover, we have successfully tested the developed autonomous solar power plant; the essence of the tests is in an experimental comparison of power generation using statically and dynamically located solar cell modules. The results of the experiments have showed that the use of a solar module with a precision dual-axis solar tracking system, in comparison with a statically located module, makes it possible to increase the efficiency of a photovoltaic installation by 50 %. Thus, experimental evidence of the effectiveness of the automate d tracking system application has been obtained. The work can be useful in the design of energy-efficient photovoltaic installations with the solar tracking system.