scholarly journals High-Efficiency Wavelet Compressive Fusion for Improving MEMS Array Performance

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1662 ◽  
Author(s):  
Siyuan Liang ◽  
Weilong Zhu ◽  
Feng Zhao ◽  
Congyi Wang

With the rapid development of microelectromechanical systems (MEMS) technology, low-cost MEMS inertial devices have been widely used for inertial navigation. However, their application range is greatly limited in some fields with high precision requirements because of their low precision and high noise. In this paper, to improve the performance of MEMS inertial devices, we propose a highly efficient optimal estimation algorithm for MEMS arrays based on wavelet compressive fusion (WCF). First, the algorithm uses the compression property of the multiscale wavelet transform to compress the original signal, fusing the compressive data based on the support. Second, threshold processing is performed on the fused wavelet coefficients. The simulation result demonstrates that the proposed algorithm performs well on the output of the inertial sensor array. Then, a ten-gyro array system is designed for collecting practical data, and the frequency of the embedded processor in our verification environment is 800 MHz. The experimental results show that, under the normal working conditions of the MEMS array system, the 100 ms input array data require an approximately 75 ms processing delay when employing the WCF algorithm to support real-time processing. Additionally, the zero-bias instability, angle random walk, and rate slope of the gyroscope are improved by 8.0, 8.0, and 9.5 dB, respectively, as compared with the original device. The experimental results demonstrate that the WCF algorithm has outstanding real-time performance and can effectively improve the accuracy of low-cost MEMS inertial devices.

2021 ◽  
Vol 11 (15) ◽  
pp. 6831
Author(s):  
Yue Chen ◽  
Jian Lu

With the rapid development of road traffic, real-time vehicle counting is very important in the construction of intelligent transportation systems (ITSs). Compared with traditional technologies, the video-based method for vehicle counting shows great importance and huge advantages in its low cost, high efficiency, and flexibility. However, many methods find difficulty in balancing the accuracy and complexity of the algorithm. For example, compared with traditional and simple methods, deep learning methods may achieve higher precision, but they also greatly increase the complexity of the algorithm. In addition to that, most of the methods only work under one mode of color, which is a waste of available information. Considering the above, a multi-loop vehicle-counting method under gray mode and RGB mode was proposed in this paper. Under gray and RGB modes, the moving vehicle can be detected more completely; with the help of multiple loops, vehicle counting could better deal with different influencing factors, such as driving behavior, traffic environment, shooting angle, etc. The experimental results show that the proposed method is able to count vehicles with more than 98.5% accuracy while dealing with different road scenes.


2020 ◽  
Vol 13 (6) ◽  
pp. 512-521
Author(s):  
Mohamed Taha ◽  
◽  
Mohamed Ibrahim ◽  
Hala Zayed ◽  
◽  
...  

Vein detection is an important issue for the medical field. There are some commercial devices for detecting veins using infrared radiation. However, most of these commercial solutions are cost-prohibitive. Recently, veins detection has attracted much attention from research teams. The main focus is on developing real-time systems with low-cost hardware. Systems developed to reduce costs suffer from low frame rates. This, in turn, makes these systems not suitable for real-world applications. On the other hand, systems that use powerful processors to produce high frame rates suffer from high costs and a lack of mobility. In this paper, a real-time vein mapping prototype using augmented reality is proposed. The proposed prototype provides a compromised solution to produce high frame rates with a low-cost system. It consists of a USB camera attached to an Android smartphone used for real-time detection. Infrared radiation is employed to differentiate the veins using 20 Infrared Light Emitting Diodes (LEDs). The captured frames are processed to enhance vein detection using light computational algorithms to improve real-time processing and increase frame rate. Finally, the enhanced view of veins appears on the smartphone screen. Portability and economic cost are taken into consideration while developing the proposed prototype. The proposed prototype is tested with people of different ages and gender, as well as using mobile devices of different specifications. The results show a high vein detection rate and a high frame rate compared to other existing systems.


Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 3001 ◽  
Author(s):  
Feng Bu ◽  
Dacheng Xu ◽  
Heming Zhao ◽  
Bo Fan ◽  
Mengmeng Cheng

In order to solve the problem where existing mode-matching methods in microelectromechanical systems (MEMS) vibrating gyroscopes fail to meet real-time and reliability requirements, this paper presents a novel method to accomplish automatic and real-time mode-matching based on phase-shifted 45° additional force demodulation (45° AFD-RM). The phase-shifted 45° additional force signal has the same frequency as the quadrature force signal, but it is phase-shifted by 45° and applied to the sense mode. In addition, two-way phase-shifted 45° demodulations are used at the sense-mode detection output to obtain a phase metric that is independent of the Coriolis force and can reflect the mode-matching state. Then, this phase metric is used as a control variable to adaptively control the tuning voltage, so as to change the sense-mode frequency through the negative stiffness effect and ultimately achieve real-time mode-matching. Simulation and experimental results show that the proposed 45° AFD-RM method can achieve real-time matching. The mode frequency split is controlled within 0.1 Hz, and the gyroscope scale factor, zero-bias instability, and angle random walk are effectively improved.


Author(s):  
Kengo Aizawa ◽  
Masahiro Ueda ◽  
Teppei Shimada ◽  
Hideki Aoyama ◽  
Kazuo Yamazaki

Abstract Laser metal deposition (LMD) is an additive manufacturing technique, whose performance can be influenced by a considerable number of factors and parameters. Typically, a powder is carried by an inert gas and sprayed by a nozzle, with a coaxial laser beam passing through the nozzle and overlapping the powder flow, thereby generating a molten material pool on a substrate. Monitoring the evolution of this process allows for a better comprehension and control of the process, thereby enhancing the deposition quality. As the metal additive manufacturing mechanism has not yet been elucidated, it is not clear how process parameters affect material properties, molding accuracy, and molding efficiency. When cladding is performed under uncertain conditions, a molded part with poor material properties and dimensional accuracy is created. In this paper, we propose a method for high efficiency molding by controlling the distance between the head nozzle and the molten pool in real time. The distance is identified by an originally developed sensor based on a triangulation method. According to the distance, the head nozzle is automatically controlled into the optimum position. As a result, an ideal molding process can be generated, so that high efficiency molding and high-quality material properties can be obtained. Experimental results show that continuing deposition at the optimum distance assists in achieving deposition efficiency and dimensional accuracy. According to the specific experimental results of this method, the modeling efficiency was increased by 27% compared to the method without correction, and the modeling was successful with an error within 1 mm.


2014 ◽  
Vol 563 ◽  
pp. 407-410
Author(s):  
Ching Tien Shih ◽  
Ching Hsiang Shih

In this paper we propose a novel Adjustable Integrating Pointing device Driver (AIPDD) using software technology to redesign mouse driver to integrate the functions of commercial pointing devices to help them to effectively utilize commercial pointing devices to operate computers. In contrast with the latest studies, the software-based AIPDD has the following benefits. (a) It does not require additional hardware cost and circuit preservation. (b) It supports all commercial pointing devices with standard interfaces of a computer, including PS/2, USB and wireless interfaces. (c) It can integrate unlimited devices simultaneously. (d) It is adjustable in real time. In summary, the AIPDD has the benefits of flexibility, low cost, high efficiency and high device compatibility. Keywords: Disabled, Computer pointing device, Mouse Integrate pointing device driver


2021 ◽  
Author(s):  
M.A. Cordova-Fajardo ◽  
E. Tututi

<div>The nanogrids are the basic unit to develop more complex and stronger distributed systems. DC nanogrids allow a better performance and higher efficiency than the AC nanogrids. The lack of DC home appliances in the local market has resulted in a slow development of DC Home Nanogrids (DCHN). The Compact Fluorescent Lamp (CFL) and LED are used in power electronics as high efficiency and low cost lightning components. However, these devices represent a source of emission of harmonics in Alternating Current (AC) and Direct Current (DC) systems, due to their nonlinear behavior. In this paper a mathematical model for the nonlinear loads and experimental results of the voltage and current ripple in a DCHN are presented. The CFL and LED lamps are used as our nonlinear loads for test the model. The model explains well the experimental results of how the ripple amplitude is reduced. We also present the effect of decreasing the ripple amplitude when it is incorporated an induction stove in standby mode to the DCHN, which also is explained by the model.</div>


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3475 ◽  
Author(s):  
Shijie Zhang ◽  
Zhenguo Gao ◽  
Di Lan ◽  
Qian Jia ◽  
Ning Liu ◽  
...  

Nitrated-pyrazole-based energetic compounds have attracted wide publicity in the field of energetic materials (EMs) due to their high heat of formation, high density, tailored thermal stability, and detonation performance. Many nitrated-pyrazole-based energetic compounds have been developed to meet the increasing demands of high power, low sensitivity, and eco-friendly environment, and they have good applications in explosives, propellants, and pyrotechnics. Continuous and growing efforts have been committed to promote the rapid development of nitrated-pyrazole-based EMs in the last decade, especially through large amounts of Chinese research. Some of the ultimate aims of nitrated-pyrazole-based materials are to develop potential candidates of castable explosives, explore novel insensitive high energy materials, search for low cost synthesis strategies, high efficiency, and green environmental protection, and further widen the applications of EMs. This review article aims to present the recent processes in the synthesis and physical and explosive performances of the nitrated-pyrazole-based Ems, including monopyrazoles with nitro, bispyrazoles with nitro, nitropyrazolo[4,3-c]pyrazoles, and their derivatives, and to comb the development trend of these compounds. This review intends to prompt fresh concepts for designing prominent high-performance nitropyrazole-based EMs.


2011 ◽  
Vol 130-134 ◽  
pp. 3938-3941
Author(s):  
Yong Gang Luo

In order to realize high-speed and real-time communications between canbus and usb bus, a can/usb embedded adapter is designed in this paper. The hardware of the system consists mainly of AT89S51 as the local processor and PDIUSBD12 as the USB interface device, the sja1000 as the canbus interface device. Data communication is operated by the firmware and drivers. Adapter completely satisfies the needs of the CAN bus with its highest speed of 1Mps and it will be widely used in future for its high efficiency and low cost.


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