scholarly journals The effect of curve running on distal limb kinematics in the Thoroughbred racehorse

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244105
Author(s):  
Rebecca S. V. Parkes ◽  
Thilo Pfau ◽  
Renate Weller ◽  
Thomas H. Witte
Keyword(s):  
Calculated Data ◽  
Measurement Unit ◽  
Large Radius ◽  
Accelerometer Data ◽  
Functional Requirements ◽  
Distal Limb ◽  
Centripetal Acceleration ◽  
Significance Level ◽  
Thoroughbred Horses ◽  
Lean Angle

During racing, injury is more likely to occur on a bend than on a straight segment of track. This study aimed to quantify the effects of galloping at training speeds on large radius curves on stride parameters and limb lean angle in order to assess estimated consequences for limb loading. Seven Thoroughbred horses were equipped with a sacrum-mounted inertial measurement unit with an integrated GPS, two hoof-mounted accelerometers and retro-reflective markers on the forelimbs. Horses galloped 2–4 circuits anticlockwise around an oval track and were filmed at 120 frames per second using an array of ten cameras. Speed and curve radius were derived from GPS data and used to estimate the centripetal acceleration necessary to navigate the curve. Stride, stance and swing durations and duty factor (DF) were derived from accelerometer data. Limb markers were tracked and whole limb and third metacarpus (MCIII) angles were calculated. Data were analysed using mixed effects models with a significance level of p < 0.05. For horses galloping on the correct lead, DF was higher for the inside (lead) leg on the straight and on the curve. For horses galloping on the incorrect lead, there was no difference in DF between inside and outside legs on the straight or on the curve. DF decreased by 0.61% of DF with each 1 m s-2 increase in centripetal acceleration (p < 0.001). Whole limb inclination angle increased by 1.5° per 1 m s-1 increase in speed (p = 0.002). Limb lean angles increase as predicted, and lead limb function mirrors the functional requirements for curve running. A more comprehensive understanding of the effects of lean and torque on the distal limb is required to understand injury mechanisms.

scholarly journals Impact of weft yarn type and fabric weft density on burning behavior, tearing strength and air permeability for different types of antibacterial drapery fabrics

2021 ◽  
Vol 69 (1) ◽  
pp. 4-16
Author(s):  
Çeven Kenan ◽  
Günaydin Karakan ◽  
Nejla Çeven
Keyword(s):  
Flame Retardant ◽  
Flame Retardancy ◽  
Air Permeability ◽  
Influential Factors ◽  
Weft Yarn ◽  
Functional Requirements ◽  
Significance Level ◽  
Antimicrobial Efficiency ◽  
Highly Correlated ◽  
Tearing Strength

Drapery fabrics are textile products utilized for home and decorative textiles. Recently there have been new functional requirements for the drapery fabrics such as flame retardancy, antimicrobial efficiency, UV protection, etc. This study has been conducted to investigate the effect of weft yarn type and weft density on drapery fabrics' burning behaviour, tearing strength and air permeability properties. "A special inherently flame-retardant yarn" was used as the warp and weft yarns of the woven drapery fabrics while "a special inherently and antibacterial yarn" was also used as the weft yarn in some of the sample groups. Two main fabric groups each consisting of 12 woven drapery samples with different weft yarns and weft densities were separately evaluated among themselves by using SPSS Statistical software package and bar graphs. Burning behaviours of the samples in terms of damage length and damage width with the ignition source were satisfying both for the drapery samples with the special inherently flame-retardant weft yarn as well as those with the special inherently flame retardant and antibacterial yarn weft yarns. In other words, usage of inherently flame retardant and antibacterial yarn as the weft yarns did not contribute negatively on the flame retardancy of drapery fabrics. The results of two-way ANOVA test indicated that weft yarn type was a significant factor for tearing strength in warp and weft wise while weft density and the interaction of weft yarn type and weft density factors were non-significant factors on tear strength values in warp and weft wises at significance level of 0.05. Additionally, correlation analyses revealed that weft yarn tenacity values were highly correlated with the drapery fabrics' weft tearing strength values. Moreover, weft yarn type, weft density and their interaction were influential factors on air permeability of the drapery fabrics at significance level of 0.05.

Residual Stress Formation at Arbitrary Types of Rollers during the Running in Process

2012 ◽  
Vol 548 ◽  
pp. 372-376
Author(s):  
O.P. Muraviev ◽  
M.R. Sikhimbayev ◽  
B.N. Absadykov ◽  
B.S. Arymbekov ◽  
Y.O. Tkacheva
Keyword(s):  
Residual Stresses ◽  
Surface Deformation ◽  
Calculated Data ◽  
Sharp Decrease ◽  
The Body ◽  
Experimental Investigations ◽  
Body Parts ◽  
Adequate Treatment ◽  
Significance Level ◽  
Plastic Surface

In the article the results of the design and analysis of mathematical model for determining residual stresses in the surface of layer at parts processed by plastic surface deformation (PSD) in which the rollers having an arbitrary shape and size. It is shown that for the calculation of stresses in the surface of layer it should not be defined by them at a forcing point but by a function of contact stresses. Integral equations are obtained for calculating the stresses in the body parts at the processing of PSD rolls of arbitrary size and shape of the stress distribution over the contact area. We found that the tangential and radial residual stresses depend on the magnitude of the force F and its distance from the point at which the voltage is considered in detail. There is a sharp decrease in the influence of forces on the stress in the surface of the part of the distance to the point in question.The calculated data generated by the proposed method are highly matches with data during the experimental investigations. Maximum deviations of the calculated values do not exceed the errors of the experiments and adequate treatment of each other at a significance level of 0.05.

scholarly journals Grip and limb force limits to turning performance in competition horses

2010 ◽  
Vol 278 (1715) ◽  
pp. 2105-2111 ◽  
Author(s):  
Huiling Tan ◽  
Alan M. Wilson
Keyword(s):  
Angular Velocity ◽  
High Speed ◽  
Small Radius ◽  
Maximum Speed ◽  
Large Radius ◽  
Centripetal Acceleration ◽  
Straight Line ◽  
Prey Interaction ◽  
The Coefficient Of Friction ◽  
Stride Parameters

Manoeuverability is a key requirement for successful terrestrial locomotion, especially on variable terrain, and is a deciding factor in predator–prey interaction. Compared with straight-line running, bend running requires additional leg force to generate centripetal acceleration. In humans, this results in a reduction in maximum speed during bend running and a published model assuming maximum limb force as a constraint accurately predicts how much a sprinter must slow down on a bend given his maximum straight-line speed. In contrast, greyhounds do not slow down or change stride parameters during bend running, which suggests that their limbs can apply the additional force for this manoeuvre. We collected horizontal speed and angular velocity of heading of horses while they turned in different scenarios during competitive polo and horse racing. The data were used to evaluate the limits of turning performance. During high-speed turns of large radius horizontal speed was lower on the bend, as would be predicted from a model assuming a limb force limit to running speed. During small radius turns the angular velocity of heading decreased with increasing speed in a manner consistent with the coefficient of friction of the hoof–surface interaction setting the limit to centripetal force to avoid slipping.

scholarly journals Real Time Estimation of the Pose of a Lower Limb Prosthesis from a Single Shank Mounted IMU

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 2865 ◽  
Author(s):  
Duraffourg ◽  
Bonnet ◽  
Dauriac ◽  
Pillet
Keyword(s):  
Real Time ◽  
Lower Limb ◽  
Time Estimation ◽  
Measurement Unit ◽  
Correct Identification ◽  
Accelerometer Data ◽  
Mode Recognition ◽  
Lower Limb Prosthesis ◽  
Real Time Estimation ◽  
Limb Prosthesis

The command of a microprocessor-controlled lower limb prosthesis classically relies on the gait mode recognition. Real time computation of the pose of the prosthesis (i.e., attitude and trajectory) is useful for the correct identification of these modes. In this paper, we present and evaluate an algorithm for the computation of the pose of a lower limb prosthesis, under the constraints of real time applications and limited computing resources. This algorithm uses a nonlinear complementary filter with a variable gain to estimate the attitude of the shank. The trajectory is then computed from the double integration of the accelerometer data corrected from the kinematics of a model of inverted pendulum rolling on a curved arc foot. The results of the proposed algorithm are evaluated against the optoelectronic measurements of walking trials of three people with transfemoral amputation. The root mean square error (RMSE) of the estimated attitude is around 3°, close to the Kalman-based algorithm results reported in similar conditions. The real time correction of the integration of the inertial measurement unit (IMU) acceleration decreases the trajectory error by a factor of 2.5 compared to its direct integration which will result in an improvement of the gait mode recognition.

scholarly journals Residual Dentin Thickness in Bifurcated Maxillary Premolars after Cervical Preflaring Preparation: A CBCT Analysis

2021 ◽  
Vol 15 (1) ◽  
pp. 495-500
Author(s):  
Gilberto Siebert Filho ◽  
Orlando Aguirre Guedes ◽  
Thiago Machado Pereira ◽  
Fabio Luís Miranda-Pedro ◽  
Andreza Maria Fábio Aranha ◽  
...  
Keyword(s):  
Calculated Data ◽  
Significance Level ◽  
Group 4 ◽  
Maxillary Premolars ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Distal Aspect ◽  
Cbct Analysis ◽  
Dentin Thickness

Objective: This study evaluated the residual dentin thickness (RDT) of maxillary premolars after the use of different cervical preflaring (PF) drills by using cone-beam computed tomography (CBCT). Methods: Eighty bifurcated maxillary premolars were accessed and randomly divided into 5 groups (n=16). PF was performed with Gates-Glidden #1, #2, and #3 (group 1), Largo #1 and #2 (group 2), and LA Axxess #20/.06 (group 3), #35/.06 (group 4), and #45/.06 (group 5). CBCT images were acquired before (preoperative) and after (postoperative) PF. Initial and final cervical dentin thickness was measured at the buccal, palatal, mesial, and distal aspects, 0.5 mm coronally to the furcation, on both buccal and palatal roots, using CBCT’s image analysis software. The percentage of removed dentin after PF preparation was also calculated. Data were analyzed using ANOVA followed by Tukey’s test at a significance level of P < 0.05. Results: No statistically significant differences were found among the groups for preoperative or postoperative RDT (P > 0.05). LA Axxess #20/.06 (group 3) removed significantly less cervical dentin at all root canal aspects on both buccal and palatal roots. The mesial aspect of the buccal root and distal aspect of the palatal root were significantly reduced after the use of LA Axxess #45/.06 (group 5) and Largo #1 and #2 drills (group 2), respectively (P < 0.05). Conclusion: PF in bifurcated maxillary premolars should be performed with LA Axxess instrument #20/.06. The use of Gates-Glidden #1, #2, and #3, Largo #1 and #2, and LA Axxess #45/.06 drills should be done with caution.

scholarly journals An Embedded Platform for Positioning and Obstacle Detection for Small Unmanned Aerial Vehicles

Electronics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1175
Author(s):  
Salvatore Ponte ◽  
Gennaro Ariante ◽  
Umberto Papa ◽  
Giuseppe Del Core
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Degrees Of Freedom ◽  
Estimation Algorithm ◽  
General Purpose ◽  
Obstacle Detection ◽  
Position Estimation ◽  
Unmanned Aircraft ◽  
Measurement Unit ◽  
Accelerometer Data ◽  
Aerial Vehicles

Unmanned Aerial Vehicles (UAV) with on-board augmentation systems (UAS, Unmanned Aircraft System) have penetrated into civil and general-purpose applications, due to advances in battery technology, control components, avionics and rapidly falling prices. This paper describes the conceptual design and the validation campaigns performed for an embedded precision Positioning, field mapping, Obstacle Detection and Avoiding (PODA) platform, which uses commercial-off-the-shelf sensors, i.e., a 10-Degrees-of-Freedom Inertial Measurement Unit (10-DoF IMU) and a Light Detection and Ranging (LiDAR), managed by an Arduino Mega 2560 microcontroller with Wi-Fi capabilities. The PODA system, designed and tested for a commercial small quadcopter (Parrot Drones SAS Ar.Drone 2.0, Paris, France), estimates position, attitude and distance of the rotorcraft from an obstacle or a landing area, sending data to a PC-based ground station. The main design issues are presented, such as the necessary corrections of the IMU data (i.e., biases and measurement noise), and Kalman filtering techniques for attitude estimation, data fusion and position estimation from accelerometer data. The real-time multiple-sensor optimal state estimation algorithm, developed for the PODA platform and implemented on the Arduino, has been tested in typical aerospace application scenarios, such as General Visual Inspection (GVI), automatic landing and obstacle detection. Experimental results and simulations of various missions show the effectiveness of the approach.

scholarly journals Model for 400 kV Transmission Line Power Loss Assessment Using the PMU Measurements

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5562
Author(s):  
Ivan Pavičić ◽  
Ninoslav Holjevac ◽  
Igor Ivanković ◽  
Dalibor Brnobić
Keyword(s):  
Transmission Line ◽  
Power Loss ◽  
Calculated Data ◽  
Weather Conditions ◽  
Measured Data ◽  
Current Data ◽  
Measurement Unit ◽  
Loss Assessment ◽  
Advanced Model ◽  
Corona Losses

This paper presents an advanced model for monitoring losses on a 400 kV over-head transmission line (OHL) that can be used for measured data verification and loss assessment. Technical losses are unavoidable physical effects of energy transmission and can be reduced to acceptable levels, with a major share of technical losses on transmission lines being Joule losses. However, at 400 kV voltage levels, the influence of the electrical corona discharge effect and current leakage can have significant impact on power loss. This is especially visible in poor weather conditions, such as the appearance of fog, rain and snow. Therefore, loss monitoring is incorporated into exiting business process to provide transmission system operators (TSO) with the measure of losses and the accurate characterization of measured data. This paper presents an advanced model for loss characterization and assessment that uses phasor measurement unit (PMU) measurements and combines them with end-customer measurements. PMU measurements from the algorithm of differential protection are used to detect differential currents and angles, and this paper proposes further usage of these data for determining the corona losses. The collected data are further processed and used to calculate the amount of corona losses and provide accurate loss assessment and estimation. In each step of the model, cross verification of the measured and calculated data is performed in order to finally provide more accurate loss assessment which is incorporated into the current data acquisition and monitoring systems.

Learning by Doing: A Simple Educational Method for Modelling Vehicle Suspensions

2018 ◽  
Author(s):  
Elisabeth Kames ◽  
David Thiess ◽  
Beshoy Morkos
Keyword(s):  
Real World ◽  
Calculated Data ◽  
Theoretical Data ◽  
Suspension System ◽  
Spring Constant ◽  
Damping Coefficient ◽  
Accelerometer Data ◽  
Educational Method ◽  
Sinusoidal Input ◽  
Quarter Car

This paper examines the educational benefit of modeling and analyzing a quarter car suspension system to simulate the vehicle response to various road inputs. The response of the vehicle was considered both theoretically and experimentally. The primary goal of the study is to test the ability to integrate similar approaches in an educational setting to allow students to gain a “real world” perspective on their theoretical coursework. Typical engineering curriculum focuses heavily on theoretical computational models. However, some students have trouble relating this calculated data to practical occurrences. This paper outlines the challenges and considerations for implementing experimental procedures into common coursework to compare to theoretical calculated data. For the theoretical model, the equation of motion of the dynamic response of the suspension system was obtained using Lagrange’s equation. Using a 2013 Jeep Wrangler Sport, the suspension spring constant, the tire spring constant, the tire damping coefficient, and the suspension damping coefficient were calculated or estimated experimentally (these parameters were used for both the theoretical and the experimental models). The combination of the MATLAB and Simulink files were used to produce visual representations of the response of the vehicle to road inputs. The experimental model is obtained using a combination of MATLAB and accelerometer data. The 2013 Jeep Wrangler was exposed to three different real-world inputs: a step up, a step down, and a sinusoidal input (a speed bump). The experimental and theoretical data is compared to exhibit trends of the vehicle to these road inputs. While the models do not align numerically, the trends of the experimental and theoretical data are shown to coincide for each of the responses. This paper will outline the quarter car model used and the mathematical model of it, the methods used to solve the model, the results obtained from the study, and the ability to integrate methods such as this into a classroom setting as a supplement.

Validity of Ski Skating Center-of-Mass Displacement Measured by a Single Inertial Measurement Unit

2015 ◽  
Vol 31 (6) ◽  
pp. 492-498 ◽  
Author(s):  
Håvard Myklebust ◽  
Øyvind Gløersen ◽  
Jostein Hallén
Keyword(s):  
Mean Squared Error ◽  
Center Of Mass ◽  
Measurement Unit ◽  
Accelerometer Data ◽  
Inertial Measurement ◽  
Accuracy And Precision ◽  
Timing Difference ◽  
Measurement Units ◽  
World Class ◽  
Mass Displacement

In regard to simplifying motion analysis and estimating center of mass (COM) in ski skating, this study addressed 3 main questions concerning the use of inertial measurement units (IMU): (1) How accurately can a single IMU estimate displacement of os sacrum (S1) on a person during ski skating? (2) Does incorporating gyroscope and accelerometer data increase accuracy and precision? (3) Moreover, how accurately does S1 determine COM displacement? Six world-class skiers roller-ski skated on a treadmill using 2 different subtechniques. An IMU including accelerometers alone (IMU-A) or in combination with gyroscopes (IMU-G) were mounted on the S1. A reflective marker at S1, and COM calculated from 3D full-body optical analysis, were used to provide reference values. IMU-A provided an accurate and precise estimate of vertical S1 displacement, but IMU-G was required to attain accuracy and precision of < 8 mm (root-mean-squared error and range of displacement deviation) in all directions and with both subtechniques. Further, arm and torso movements affected COM, but not the S1. Hence, S1 displacement was valid for estimating sideways COM displacement, but the systematic amplitude and timing difference between S1 and COM displacement in the anteroposterior and vertical directions inhibits exact calculation of energy fluctuations.

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