Read by QxMD icon Read


Hairong Chu, Tingting Sun, Baiqiang Zhang, Hongwei Zhang, Yang Chen
In airborne MEMS SINS transfer alignment, the error of MEMS IMU is highly environment-dependent and the parameters of the system model are also uncertain, which may lead to large error and bad convergence of the Kalman filter. In order to solve this problem, an improved adaptive incremental Kalman filter (AIKF) algorithm is proposed. First, the model of SINS transfer alignment is defined based on the "Velocity and Attitude" matching method. Then the detailed algorithm progress of AIKF and its recurrence formulas are presented...
January 14, 2017: Sensors
Daniel Kelly, Kevin Curran, Brian Caulfield
OBJECTIVE: Current methods of assessing the affect a patients' health has on their daily life are extremely limited. The aim of this work is to develop a sensor based approach to health status measurement in order to objectively measure health status. METHODS: Techniques to generate human behaviour profiles, derived from smartphone accelerometer and gyroscope sensors, are proposed. Experiments, using SVM regression models, are then conducted in order to evaluate the use of the proposed behaviour profiles as a predictor of health status...
January 9, 2017: IEEE Journal of Biomedical and Health Informatics
Kun Qian, Jun Tang, Hao Guo, Wenyao Liu, Jun Liu, Chenyang Xue, Yongqiu Zheng, Chengfei Zhang
As an important sensing element, the whispering gallery mode resonator (WGMR) parameters seriously affect the resonant micro-optic gyroscope (RMOG) performance. This work proposes an under-coupling resonator to improve the resonator's Q value and to optimize the coupling coefficient to maximize the RMOG's sensitivity. GeO₂-doped silica waveguide-type resonators with different coupling coefficients were simulated, designed, fabricated and tested. An under-coupling ring resonator with a quality factor of 10 million is reported...
January 6, 2017: Sensors
Jeong-Suong Yang, Yunsung Kang, Inyoung Kang, Seungmo Lim, Seung-Joo Shin, Jungwon Lee, Kangheon Hur
The degradation of Niobium-doped lead zirconate titanate (PZT) and two types of PZT thin films were investigated. Undoped PZT, 2-step PZT and heavily Nb-doped PZT (PNZT) around the morphotropic phase boundary (MPB) were in-situ deposited under optimum condition by RF-magnetron sputtering. All 2 μm thick films had dense perovskite columnar grain structure and self-polarized (100) dominant orientation. PZT thin films were deposited on Pt/TiOx bottom electrode on Si wafer, and Nb doped PZT thin film was on Ir/TiW electrode with help of orientation control...
January 4, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
K Imura, T Fujibuchi, K Kaneko, E Hamada, H Hirata
PURPOSE: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. METHODS: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity)...
June 2016: Medical Physics
Katelyn Cahill-Rowley, Jessica Rose
Reaching is a well-practiced functional task crucial to daily living activities, and temporal-spatial measures of reaching reflect function for both adult and pediatric populations with upper-extremity motor impairments. Inertial sensors offer a mobile and inexpensive tool for clinical assessment of movement. This research outlines a method for measuring temporal-spatial reach parameters using inertial sensors, and validates these measures with traditional marker-based motion capture. 140 reaches from 10 adults, and 30 reaches from nine children aged 18-20 months, were recorded and analyzed using both inertial-sensor and motion-capture methods...
October 26, 2016: Journal of Biomechanics
Chengfeng Xie, Jun Tang, Danfeng Cui, Dajin Wu, Chengfei Zhang, Chunming Li, Yongqiu Zhen, Chenyang Xue, Jun Liu
The resonant microsphere gyroscope is proposed based on a double Faraday rotator system for the resonant microsphere gyroscope (RMSG) that is characterized by low insertion losses and does not destroy the reciprocity of the gyroscope system. Use of the echo suppression structure and the orthogonal polarization method can effectively inhibit both the backscattering noise and the polarization error, and reduce them below the system sensitivity limit. The resonance asymmetry rate dropped from 34.2% to 2.9% after optimization of the backscattering noise and the polarization noise, which greatly improved the bias stability and the scale factor linearity of the proposed system...
October 15, 2016: Optics Letters
Leszek R Jaroszewicz, Anna Kurzych, Zbigniew Krajewski, Paweł Marć, Jerzy K Kowalski, Piotr Bobra, Zbigniew Zembaty, Bartosz Sakowicz, Robert Jankowski
Starting with descriptions of rotational seismology, areas of interest and historical field measurements, the fundamental requirements for rotational seismometers for seismological and engineering application are formulated. On the above basis, a review of all existing rotational seismometers is presented with a description of the principles of their operation as well as possibilities to fulfill formulated requirements. This review includes mechanical, acoustical, electrochemical and optical devices and shows that the last of these types are the most promising...
December 16, 2016: Sensors
Yun Li, Wenqi Wu, Qingan Jiang, Jinling Wang
Based on stochastic modeling of Coriolis vibration gyros by the Allan variance technique, this paper discusses Angle Random Walk (ARW), Rate Random Walk (RRW) and Markov process gyroscope noises which have significant impacts on the North-finding accuracy. A new continuous rotation alignment algorithm for a Coriolis vibration gyroscope Inertial Measurement Unit (IMU) is proposed in this paper, in which the extended observation equations are used for the Kalman filter to enhance the estimation of gyro drift errors, thus improving the north-finding accuracy...
December 13, 2016: Sensors
Jacob Chamoun, Michel J F Digonnet
Low noise and drift in a laser-driven fiber optic gyroscope (FOG) are demonstrated by interrogating the sensor with a low-coherence laser. The laser coherence was reduced by broadening its optical spectrum using an external electro-optic phase modulator driven by either a sinusoidal or a pseudo-random bit sequence (PRBS) waveform. The noise reduction measured in a FOG driven by a modulated laser agrees with the calculations based on the broadened laser spectrum. Using PRBS modulation, the linewidth of a laser was broadened from 10 MHz to more than 10 GHz, leading to a measured FOG noise of only 0...
December 15, 2016: Optics Letters
Sang Cheol Lee, Sung Kyung Hong
This paper presents an algorithm for velocity-aided attitude estimation for helicopter aircraft using a microelectromechanical system inertial-measurement unit. In general, high- performance gyroscopes are used for estimating the attitude of a helicopter, but this type of sensor is very expensive. When designing a cost-effective attitude system, attitude can be estimated by fusing a low cost accelerometer and a gyro, but the disadvantage of this method is its relatively low accuracy. The accelerometer output includes a component that occurs primarily as the aircraft turns, as well as the gravitational acceleration...
December 11, 2016: Sensors
Hafiz Farhan Maqbool, Muhammad Afif Bin Husman, Mohammed I Awad, Alireza Abouhossein, Nadeem Iqbal, Abbas A Dehghani-Sanij
Lower extremity amputees suffer from mobility limitations which will result in a degradation of their quality of life. Wearable sensors are frequently used to assess spatio-temporal, kinematic and kinetic parameters providing the means to establish an interactive control of the amputee-prosthesis-environment system. Gait events and the gait phase detection of an amputee's locomotion are vital for controlling lower limb prosthetic devices. The paper presents an approach to real-time gait event detection for lower limb amputees using a wireless gyroscope attached to the shank when performing level ground and ramp activities...
December 7, 2016: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Jian Lin, Jiaming Liu, Hao Zhang, Wenxiu Li, Lu Zhao, Junjie Jin, Anping Huang, Xiaofu Zhang, Zhisong Xiao
Rigorous expressions of resonant frequency shift (RFS) in anomalous dispersion enhanced resonant optical gyroscopes (ADEROGs) are deduced without making approximation, which provides a precise theoretical guidance to achieve ultra-sensitive ADEROGs. A refractive index related modification factor is introduced when considering special theory of relativity (STR). We demonstrate that the RFS will not be "infinitely large" by using critical anomalous dispersion (CAD) and negative modification does not exist, which make the mechanism of anomalous dispersion enhancement clear and coherent...
December 12, 2016: Scientific Reports
Lu Wang, Chunxi Zhang, Shuang Gao, Tao Wang, Tie Lin, Xianmu Li
The stability of a fiber optic gyroscope (FOG) in measurement while drilling (MWD) could vary with time because of changing temperature, high vibration, and sudden power failure. The dynamic Allan variance (DAVAR) is a sliding version of the Allan variance. It is a practical tool that could represent the non-stationary behavior of the gyroscope signal. Since the normal DAVAR takes too long to deal with long time series, a fast DAVAR algorithm has been developed to accelerate the computation speed. However, both the normal DAVAR algorithm and the fast algorithm become invalid for discontinuous time series...
December 7, 2016: Sensors
Shu-Yin Chiang, Yao-Chiang Kan, Yun-Shan Chen, Ying-Ching Tu, Hsueh-Chun Lin
Ubiquitous health care (UHC) is beneficial for patients to ensure they complete therapeutic exercises by self-management at home. We designed a fuzzy computing model that enables recognizing assigned movements in UHC with privacy. The movements are measured by the self-developed body motion sensor, which combines both accelerometer and gyroscope chips to make an inertial sensing node compliant with a wireless sensor network (WSN). The fuzzy logic process was studied to calculate the sensor signals that would entail necessary features of static postures and dynamic motions...
December 3, 2016: Sensors
Bhargava Teja Nukala, Taro Nakano, Amanda Rodriguez, Jerry Tsay, Jerry Lopez, Tam Q Nguyen, Steven Zupancic, Donald Y C Lie
Gait analysis using wearable wireless sensors can be an economical, convenient and effective way to provide diagnostic and clinical information for various health-related issues. In this work, our custom designed low-cost wireless gait analysis sensor that contains a basic inertial measurement unit (IMU) was used to collect the gait data for four patients diagnosed with balance disorders and additionally three normal subjects, each performing the Dynamic Gait Index (DGI) tests while wearing the custom wireless gait analysis sensor (WGAS)...
November 29, 2016: Biosensors
A Acker, J-F Fischer, K Aminian, E Lécureux, B M Jolles
BACKGROUND: Rates of dislocation following primary total hip arthroplasty (THA) vary from 0.5 to 10%. Dual-mobility cups in THA demonstrate increased stability. Clinical outcomes following THA with dual-mobility cups have been reported, but gait has not been assessed. Therefore we performed a retrospective case control study to answer: (1) is gait better in patients following THA with a dual-mobility cup than in frail, elderly patients of the same age? (2) Are clinical outcomes better in patients following THA with a dual-mobility cup than in frail, elderly patients? (3) What is the dislocation rate following THA with a dual-mobility cup? HYPOTHESIS: We hypothesized that patients who underwent THA with a dual-mobility cup have a better gait compared to frail, elderly patients of the same age...
November 24, 2016: Orthopaedics & Traumatology, Surgery & Research: OTSR
Stephen Ragole, Jacob M Taylor
Atom interferometers provide exquisite measurements of the properties of noninertial frames. While atomic interactions are typically detrimental to good sensing, efforts to harness entanglement to improve sensitivity remain tantalizing. Here we explore the role of interactions in an analogy between atomic gyroscopes and SQUIDs, motivated by recent experiments realizing ring-shaped traps for ultracold atoms. We explore the one-dimensional limit of these ring systems with a moving weak barrier, such as that provided by a blue-detuned laser beam...
November 11, 2016: Physical Review Letters
Marek Strzała, Arkadiusz Stanula, Andrzej Ostrowski, Marcin Kaca, Piotr Kreżałek, Jacek Głodzik
BACKGROUND: This work is aimed at examining how coordination and kinematic indices interplay with swimming performance measured by average speed in 50m all-out test. METHODS: The group of 34 male competitive swimmers (19.1± 1.91 years old) participated in the study. The underwater movements of swimmers' bodies were recorded providing side- shots. Accelerations and angular velocity of pitch rotation of swimmer's sacrum were measured with inertial sensor device (three-axial accelerometer and gyroscope)...
November 24, 2016: Journal of Sports Medicine and Physical Fitness
L S Cuijpers, P J M Passos, A Murgia, A Hoogerheide, K A P M Lemmink, H J de Poel
In crew rowing, crew members need to mutually synchronize their movements to achieve optimal crew performance. Intuitively, poor crew coordination is often deemed to involve additional boat movements such as surge velocity fluctuations, heave, pitch, and roll, which would imply lower efficiency (eg, due to increased hydrodynamic drag). The aim of this study was to investigate this alleged relation between crew coordination and boat movements at different stroke rates. Fifteen crews of two rowers rowed in a double scull (ie, a two-person boat) at 18, 22, 26, 30, and 34 strokes per minute...
November 23, 2016: Scandinavian Journal of Medicine & Science in Sports
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"