scholarly journals Development of a low-cost six-axis alignment instrument for flexible 2D and 3D ultrasonic probes

2021 ◽  
Vol 29 ◽  
pp. 77-84
Author(s):  
Jungsuk Kim ◽  
Kwang Soo Kim ◽  
Hojong Choi
Keyword(s):  
Error Rate ◽  
Low Cost ◽  
Maximum Error ◽  
Axis Alignment ◽  
Left And Right ◽  
Pulse Echo ◽  
2D And 3D ◽  
Long Operation

BACKGROUND: The pulse-echo test is used to evaluate the performance of ultrasonic probes before manufacturing ultrasonic systems. However, commercial alignment instruments are very large and use complex programs with long operation times. OBJECTIVE: To develop a low-cost alignment instrument used in the pulse-echo test for evaluating the performance of various 2D and 3D ultrasonic probes. METHODS: The developed alignment instrument can be aligned with the X, Y, Z, azimuth, elevation, and tilt axes with manual structure to support mounting fixtures that hold 2D and 3D ultrasonic probes. Each axis has a manual lever and is designed to have no movement when fixed. In particular, tilt and azimuth directions are designed to move more than 5∘ left and right. RESULTS: The probe mounted in the X, Y, and Z axes can move at above 50 mm. The probe mounted in the azimuth, elevation, and tilt axes can move more than 5∘ in the left and right directions. The pulse-echo test using commercial ultrasonic probes showed maximum error rate of less than 5%. CONCLUSIONS: Our developed alignment instrument can reduce costs by eliminating the need for shortening inspection times for probe manufacturers.

EFFECT OF THE POSITION OF THE CORONARY SINUS ORIFICE ON AORTIC LEAFLET COAPTATION

2014 ◽  
Vol 14 (06) ◽  
pp. 1440009
Author(s):  
YOULIAN PAN ◽  
AIKE QIAO ◽  
NIANGUO DONG
Keyword(s):  
Aortic Valve ◽  
Coronary Sinus ◽  
Aortic Root ◽  
Computational Simulation ◽  
Aortic Leaflet ◽  
Left And Right ◽  
Leaflet Coaptation ◽  
Geometric Relationship ◽  
2D And 3D ◽  
Sinus Pressure

Background: The various components of the aortic root maintain a particular geometric relationship to guarantee unobstructed blood flow across the aortic valve and valve competence. Objective: To quantify the effect of the position of the coronary sinus orifice (CSO) on aortic leaflet coaptation. Methods: 2D and 3D finite element models of an aortic valve and root were constructed, with the CSO located on the bottom and middle of the sinuses. ADINA fluid-structure interaction solver was employed to perform computational simulation. Results: The mean sinus pressure with left and right CSO was 1.02E+4 Pa and 1.03E+4 Pa, respectively, and the average leaflet pressure with left and right CSO was 1.06E+4 Pa and 1.05E+4 Pa, respectively, for the model with CSO located in the middle and bottom of the sinus. The leaflet summit displacement differences of the CSO position on the bottom and middle between left and right coronary sinuses and none were 11.56, -107.57, 16.17 and -92.86 μm, respectively. Conclusions: The position of the CSO affects the pressure distribution of the aortic root. The local high pressure results in symmetrical deformation of the three leaflets, and decreases the risk of leaflet mismatch in coaptation.

scholarly journals Performance Evaluation of Autonomous Driving Control Algorithm for a Crawler-Type Agricultural Vehicle Based on Low-Cost Multi-Sensor Fusion Positioning

2020 ◽  
Vol 10 (13) ◽  
pp. 4667 ◽  
Author(s):  
Joong-hee Han ◽  
Chi-ho Park ◽  
Jay Hyoun Kwon ◽  
Jisun Lee ◽  
Tae Soo Kim ◽  
...  
Keyword(s):  
Control Algorithm ◽  
Low Cost ◽  
Autonomous Driving ◽  
Maximum Error ◽  
Sensor Technology ◽  
Motion Sensor ◽  
Integration Algorithm ◽  
Sensor Module ◽  
Agricultural Vehicle ◽  
Mean Square Errors

The agriculture sector is currently facing the problems of aging and decreasing skilled labor, meaning that the future direction of agriculture will be a transition to automation and mechanization that can maximize efficiency and decrease costs. Moreover, interest in the development of autonomous agricultural vehicles is increasing due to advances in sensor technology and information and communication technology (ICT). Therefore, an autonomous driving control algorithm using a low-cost global navigation satellite system (GNSS)-real-time kinematic (RTK) module and a low-cost motion sensor module was developed to commercialize an autonomous driving system for a crawler-type agricultural vehicle. Moreover, an autonomous driving control algorithm, including the GNSS-RTK/motion sensor integration algorithm and the path-tracking control algorithm, was proposed. Then, the performance of the proposed algorithm was evaluated based on three trajectories. The Root Mean Square Errors (RMSEs) of the path-following of each trajectory are calculated to be 9, 7, and 7 cm, respectively, and the maximum error is smaller than 30 cm. Thus, it is expected that the proposed algorithm could be used to conduct autonomous driving with about a 10 cm-level of accuracy.

scholarly journals Simple Assessment of Height and Length of Flight in Complex Gymnastic Skills: Validity and Reliability of a Two-Dimensional Video Analysis Method

2019 ◽  
Vol 9 (19) ◽  
pp. 3975 ◽  
Author(s):  
Christoph Schärer ◽  
Luca von Siebenthal ◽  
Ishbel Lomax ◽  
Micah Gross ◽  
Wolfgang Taube ◽  
...  
Keyword(s):  
Video Analysis ◽  
Interrater Reliability ◽  
Average Length ◽  
Low Cost ◽  
Peak Height ◽  
3D Analysis ◽  
Random Errors ◽  
Validity And Reliability ◽  
Intrarater Reliability ◽  
2D And 3D

In artistic gymnastics, the possibility of using 2D video analysis to measure the peak height (hpeak) and length of flight (L) during routine training in order to monitor the execution and development of difficult elements is intriguing. However, the validity and reliability of such measurements remain unclear. Therefore, in this study, the hpeak and L of 38 vaults, performed by top-level gymnasts, were assessed by 2D and 3D analysis in order to evaluate criterion validity and both intrarater and interrater reliability of the 2D method. Validity calculations showed higher accuracy for hpeak (±95% LoA: ±3.6% of average peak height) than for L (±95% LoA: ±7.6% of average length). Minor random errors, but no systematic errors, were observed in the examination of intrarater reliability (hpeak: CV% = 0.44%, p = 0.81; L: CV% = 0.87%, p = 0.14) and interrater reliability (hpeak: CV% = 0.51%, p = 0.55; L: CV% = 0.72%, p = 0.44). In conclusion, the validity and reliability of the 2D method are deemed sufficient (particularly for hpeak, but with some limitations for L) to justify its use in routine training of the vault. Due to its simplicity and low cost, this method could be an attractive monitoring tool for gymnastics coaches.

Linear and Nonlinear Model of Cutting Forces in Peripheral Milling: A Comparison Between 2D and 3D Models

2010 ◽  
Author(s):  
Hamed Moradi ◽  
Mohammad R. Movahhedy ◽  
Gholamreza Vossoughi
Keyword(s):  
Cutting Forces ◽  
Nonlinear Models ◽  
Three Dimensional ◽  
Chip Thickness ◽  
Maximum Error ◽  
3D Models ◽  
Peripheral Milling ◽  
Third Order ◽  
Order Polynomial ◽  
2D And 3D

Peripheral milling is extensively used in manufacturing processes, especially in aerospace industry where end mills are used for milling of wing parts and engine components. Knowledge of the cutting forces is the first necessary stage in analysis of the milling process. In this paper, cutting forces are presented for both two and three dimensional models. Instead of the common linear dependency of cutting forces to the cut chip thickness, two nonlinear models are presented. In the first model, cutting forces are considered as a function of chip thickness with a complete third order polynomial. In the second one, the quadratic and constant terms of the third order polynomial are set to zero. Results show about 2–3% and 2–7% maximum error between the linear, first and second nonlinear models, for 2D and 3D models, respectively. According to the simulation results, both the 2D and 3D models with second type of nonlinearity can be effectively used in practice. The advantage of such modelling is its simplicity in nonlinear analysis of the problem based on perturbation techniques.

Collapse characteristics of a circular-cross-section CFRP pipe structure member using finite element analysis

e-Polymers ◽  
2018 ◽  
Vol 18 (1) ◽  
pp. 27-33
Author(s):  
Dae Young Kim ◽  
Hee Seong Kim ◽  
Ji Hoon Kim
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Composite Materials ◽  
Carbon Fibers ◽  
Error Rate ◽  
Material Properties ◽  
Structural Characteristics ◽  
Circular Cross Section ◽  
Maximum Error ◽  
Element Analysis

AbstractCarbon fiber reinforced plastics (CFRPs) are advanced composite materials that have been used as lightweight structural materials for vehicles. Unlike general isotropic materials, the structural characteristics of composite materials are strongly influenced by the stacking directions and sequences of the composite laminates. In this study, finite element analysis was used to predict the material properties of the carbon fibers and the resin composing a CFRP in cases of laminated carbon fibers and modified external angles. The results verify the approach’s reliability by comparing the simulation results and the real test results related to the material properties of the carbon fibers and the resin. The results of the finite element analysis and the experimental results were compared with the load-displacement curves and the maximum load. The [02/902]S, [902/02]2, and [0/90]2S specimens showed a maximum error rate of 8.6%, whereas the [902/02]S, [02/902]2, and [90/0]2S specimens showed a maximum error rate of approximately 12.93%. By applying CFRP static collapse analysis of fiber properties and resin properties through basic experiments and basic theory, we predicted the properties of CFRPs through finite element analysis; an error rate of approximately 10% indicated that our approach is effective.

scholarly journals CO3D, A WORLDWIDE ONE ONE-METER ACCURACY DEM FOR 2025

2020 ◽  
Vol XLIII-B1-2020 ◽  
pp. 299-304
Author(s):  
L. Lebègue ◽  
E. Cazala-Hourcade ◽  
F. Languille ◽  
S. Artigues ◽  
O. Melet
Keyword(s):  
Near Infrared ◽  
Low Cost ◽  
Infrared Band ◽  
Automatic Production ◽  
Worldwide Production ◽  
Expected Performance ◽  
Absolute Height ◽  
Dem Accuracy ◽  
New Generation ◽  
2D And 3D

Abstract. The goal of the CO3D (Constellation Optique 3D) mission is the full-automatic production of a worldwide accurate DEM. CO3D is also a constellation of a new generation of low-cost optical satellites. The DEM accuracy is expected to be one meter in relative height and two meters in absolute height with a one-meter grid space. Each of the four satellites of the constellation will provide images with 0.50 m resolution in red, green, blue bands. A NIR (Near-InfraRed) band will also be available with a resolution close to 1 m. The satellites resource will be shared by, on one hand, the French institutions (government, scientists concerned by global Earth monitoring) who will have dedicated access and preferred price conditions, and on the other hand commercial customers interested in 2D and 3D products. The launch of the constellation is expected mid-2023 and 90 % of the DEM worldwide production should be reached by the end of 2025.Starting from an overview of the system characteristics and its main innovations, this paper presents the expected performance, the 2D and 3D products that should be available for the end-users and finally how they should be qualified.

scholarly journals BILATERAL INSTRUMENTED WHEEL SYSTEM FOR MEASURING HANDRIM FORCES DURING MANUAL WHEELCHAIR PROPULSION

2020 ◽  
Vol 20 (10) ◽  
pp. 2040040
Author(s):  
YONG CHEOL KIM ◽  
YOON HEO ◽  
KI-TAE NAM ◽  
GYOO SUK KIM ◽  
EUNG-PYO HONG
Keyword(s):  
Maximum Error ◽  
Wheelchair Propulsion ◽  
Dynamic Tests ◽  
Manual Wheelchair ◽  
Acceptable Accuracy ◽  
Torque Measurements ◽  
Reaction Forces ◽  
Left And Right ◽  
Static And Dynamic Tests ◽  
Highly Correlated

The purpose of this study was to design and validate a new bilateral instrumented wheel system (IWS) to measure triaxial handrim forces and torques simultaneously during the wheelchair propulsion. The designed and implemented system measures the force applied to the handrims on both sides of a manual wheelchair using 6-axis force/torque sensors. In addition, a user interface receives the measurements from the left and right IWSs. To verify the accuracy of the wheel system, we evaluate force and torque measurements during the static and dynamic tests. The maximum error in static measurements of force and torque are 4.29% and 1.95%, respectively. Likewise, dynamic tests using planar forces and axle torques provide low errors and measurements that are highly correlated with the expected values ([Formula: see text]). The results revealed that the proposed IWS can be used to measure bilateral 3D handrim reaction forces with acceptable accuracy.

scholarly journals CoDRIVE – Delivering High Accuracy, Ubiquitous Positioning Through Combined Radio Navigation and Inertial Sensing Technologies

2020 ◽  
Author(s):  
Simon Roberts
Keyword(s):  
Radio Frequency Identification ◽  
Autonomous Vehicles ◽  
Low Cost ◽  
Maximum Error ◽  
Precision Data ◽  
The Road ◽  
Frequency Identification ◽  
High Precision Data ◽  
On The Road ◽  
The University

The CoDRIVE solution builds on R&D in the development of connected and autonomous vehicles (CAVs). The mainstay of the system is a low-cost GNSS receiver integrated with a MEMS grade IMU powered with CoDRIVE algorithms and high precision data processing software. The solution integrates RFID (radio-frequency identification) localisation information derived from tags installed in the roads around the University of Nottingham. This aids the positioning solution by correcting the long-term drift of inertial navigation technology in the absence of GNSS. The solution is informed of obscuration of GNSS through city models of skyview and elevation masks derived from 360-degree photography. The results show that predictive intelligence of the denial of GNSS and RFID aiding realises significant benefits compared to the inertial only solution. According to the validation, inertial only solutions drift over time, with an overall RMS accuracy over a 300 metres section of GNSS outage of 10 to 20 metres. After deploying the RFID tags on the road, experiments show that the RFID aided algorithm is able to constrain the maximum error to within 3.76 metres, and with 93.9% of points constrained to 2 metres accuracy overall.

scholarly journals 2D AND 3D PLOTTER USING ARDUINO NANO

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jagadeesh Kumar Chougala ◽  
Kirankumar S Patil ◽  
Jayanth H S ◽  
Santhosh M P ◽  
Chaitanya L
Keyword(s):  
Low Cost ◽  
High Accuracy ◽  
Small Scale ◽  
Performance Parameters ◽  
Cnc Machine ◽  
2D And 3D

This paper aims to develop and implement a low cost and high accuracy mini-CNC machine for 2D and 3D plotting using Arduino Nano. This system can be widely used in small-scale engraving or Image plotting applications where the accuracy and speed are the main performance parameters.

scholarly journals An Evaluation of Temporal and Club Angle Parameters During Golf Swings Using Low Cost Video Analyses Packages

2022 ◽  
Author(s):  
Henry H. Hunter ◽  
Ukadike C. Ugbolue ◽  
Graeme G. Sorbie ◽  
Wing-Kai Lam ◽  
Fergal M. Grace ◽  
...  
Keyword(s):  
High Speed ◽  
Low Cost ◽  
Cost Effective ◽  
Video Camera ◽  
Golf Club ◽  
Phase Measurements ◽  
Swing Time ◽  
The Cost ◽  
3D Software ◽  
2D And 3D

Abstract The purpose of this study was to compare swing time and golf club angle parameters during golf swings using three, two dimensional (2D) low cost, Augmented-Video-based-Portable-Systems (AVPS) (Kinovea, SiliconCoach Pro, SiliconCoach Live). Twelve right-handed golfers performed three golf swings whilst being recorded by a high-speed 2D video camera. Footage was then analysed using AVPS-software and the results compared using both descriptive and inferential statistics. There were no significant differences for swing time and the golf phase measurements between the 2D and 3D software comparisons. In general, the results showed a high Intra class Correlation Coefficient (ICC > 0.929) and Cronbach’s Coefficient Alpha (CCA > 0.924) reliability for both the kinematic and temporal parameters. The inter-rater reliability test for the swing time and kinematic golf phase measurements on average were strong. Irrespective of the AVPS software investigated, the cost effective AVPS can produce reliable output measures that benefit golf analyses.

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