scholarly journals Drift Reduction of a 4-DOF Measurement System Caused by Unstable Air Refractive Index

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6329
Author(s):  
Ruijun Li ◽  
Yongjun Wang ◽  
Pan Tao ◽  
Rongjun Cheng ◽  
Zhenying Cheng ◽  
...  
Keyword(s):  
Refractive Index ◽  
Laser Beam ◽  
Measurement System ◽  
Degrees Of Freedom ◽  
Cost Effective ◽  
Control Mode ◽  
Detection Accuracy ◽  
Long Distance ◽  
Cost Effective Method ◽  
Novel Method

Laser beam drift greatly influences the accuracy of a four degrees of freedom (4-DOF) measurement system during the detection of machine tool errors, especially for long-distance measurement. A novel method was proposed using bellows to serve as a laser beam shield and air pumps to stabilize the refractive index of air. The inner diameter of the bellows and the control mode of the pumps were optimized through theoretical analysis and simulation. An experimental setup was established to verify the feasibility of the method under the temperature interference condition. The results indicated that the position stability of the laser beam spot can be improved by more than 79% under the action of pumping and inflating. The proposed scheme provides a cost-effective method to reduce the laser beam drift, which can be applied to improve the detection accuracy of a 4-DOF measurement system.

scholarly journals Accurate Measurement of Handwash Quality Using Sensor Armbands: Instrument Validation Study (Preprint)

2019 ◽  
Author(s):  
Chaofan Wang ◽  
Zhanna Sarsenbayeva ◽  
Xiuge Chen ◽  
Tilman Dingler ◽  
Jorge Goncalves ◽  
...  
Keyword(s):  
Health Care ◽  
Hand Hygiene ◽  
Cost Effective ◽  
Video Data ◽  
World Health ◽  
Detection Accuracy ◽  
Cost Effective Method ◽  
Health Care Associated Infections ◽  
Dependent Model ◽  
Health Organization

BACKGROUND Hand hygiene is a crucial and cost-effective method to prevent health care–associated infections, and in 2009, the World Health Organization (WHO) issued guidelines to encourage and standardize hand hygiene procedures. However, a common challenge in health care settings is low adherence, leading to low handwashing quality. Recent advances in machine learning and wearable sensing have made it possible to accurately measure handwashing quality for the purposes of training, feedback, or accreditation. OBJECTIVE We measured the accuracy of a sensor armband (Myo armband) in detecting the steps and duration of the WHO procedures for handwashing and handrubbing. METHODS We recruited 20 participants (10 females; mean age 26.5 years, SD 3.3). In a semistructured environment, we collected armband data (acceleration, gyroscope, orientation, and surface electromyography data) and video data from each participant during 15 handrub and 15 handwash sessions. We evaluated the detection accuracy for different armband placements, sensor configurations, user-dependent vs user-independent models, and the use of bootstrapping. RESULTS Using a single armband, the accuracy was 96% (SD 0.01) for the user-dependent model and 82% (SD 0.08) for the user-independent model. This increased when using two armbands to 97% (SD 0.01) and 91% (SD 0.04), respectively. Performance increased when the armband was placed on the forearm (user dependent: 97%, SD 0.01; and user independent: 91%, SD 0.04) and decreased when placed on the arm (user dependent: 96%, SD 0.01; and user independent: 80%, SD 0.06). In terms of bootstrapping, user-dependent models can achieve more than 80% accuracy after six training sessions and 90% with 16 sessions. Finally, we found that the combination of accelerometer and gyroscope minimizes power consumption and cost while maximizing performance. CONCLUSIONS A sensor armband can be used to measure hand hygiene quality relatively accurately, in terms of both handwashing and handrubbing. The performance is acceptable using a single armband worn in the upper arm but can substantially improve by placing the armband on the forearm or by using two armbands. CLINICALTRIAL

From couch to ultra marathon: using functional imagery training to enhance motivation

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jonathan Rhodes ◽  
Karol Nedza ◽  
Jon May ◽  
Thomas Jenkins ◽  
Tom Stone
Keyword(s):  
Goal Setting ◽  
Exercise Adherence ◽  
Cost Effective ◽  
Group Setting ◽  
Long Distance ◽  
Marathon Runners ◽  
Imagery Training ◽  
Long Distance Running ◽  
Cost Effective Method ◽  
Contact Hours

Abstract Objectives This study evaluates ultra-marathon runners’ use of goal-setting, self-talk, and imagery as strategies to help them through the challenge of long-distance running. Methods In stage one, thirty-one self-professed non-runners were recruited and received motivational interviewing (MI) in a group setting, examining their motivation to get healthy. In stage two, five months later, participants were asked if they would consider running an ultra-marathon, and fifteen (M age=39.47, SD=5.84) agreed. At this point participants were randomly split into an MI or Functional Imagery Training (FIT) group. FIT teaches participants how to master goal centred imagery by controlling attention and elaboration. Groups received similar contact hours and completed four measures that assess grit, resilience, self-efficacy, and imagery ability at baseline and after the race. Results We found no significant differences between measures for finishers and non-finishers or between groups or over time. However, the likelihood of completing the ultra-marathon was five times as likely in the FIT group, than in MI (RR=5.25). Grit and resilience scores were strongly correlated. By receiving FIT, there was a significant association (p=0.04) to complete the ultra-marathon. Conclusions FIT is a relatively cost-effective method to increase exercise adherence through multi-sensory elaboration of goal setting and overcoming barriers or challenges.

Real-Time Monitoring Method for Five-Degrees-of-Freedom of the Extruder’s Moving Parts

2011 ◽  
Vol 105-107 ◽  
pp. 630-634 ◽  
Author(s):  
Xian Wang ◽  
Jian Ping Tan ◽  
Ling Yun Quan ◽  
Xiao Le Cheng
Keyword(s):  
Machine Vision ◽  
Laser Beam ◽  
Real Time ◽  
Digital Signal Processor ◽  
High Speed ◽  
Degrees Of Freedom ◽  
Real Time Monitoring ◽  
Long Distance ◽  
Monitoring Method ◽  
Moving Parts

On the basis of systematic study on the existing measurement methods of multi-degrees-of-freedom, A real-time monitoring method for five-degrees-of-freedom of the extruder’s moving parts was proposed based on laser beam measurement reference and machine vision. Simultaneously measuring multi-degrees-of-freedom is implemented by two-collimated laser beam and three-point measurement in this method, laser dispersion technology is used for several measuring points using the same basis simultaneously, the baseline errors are initial adjusted and real-time monitored, the method of machine vision is used for precise extraction of the position signals. Position signals are collected and selected by a Charge Coupled Device (CCD) sensor and a high speed Digital Signal Processor (DSP), long-distance propagation and reconciliation of multi-channel data is implemented by an industrial Ethernet. Experiments indicated the method is effective and steady.

Methods for accurate measurements of small fixed wing UAV inertial properties

2016 ◽  
Vol 120 (1233) ◽  
pp. 1785-1811 ◽  
Author(s):  
K. Lehmkühler ◽  
K.C. Wong ◽  
D. Verstraete
Keyword(s):  
Degrees Of Freedom ◽  
Wind Tunnel Test ◽  
Cost Effective ◽  
Mass Effect ◽  
Small Scale ◽  
Pendulum Motion ◽  
Single Degree Of Freedom ◽  
Cost Effective Method ◽  
Aerial Vehicle

ABSTRACTTwo methods have been compared for the determination of the inertial properties of a small, fixed-wing un-manned aerial vehicle. The first method uses the standard single degree of freedom pendulum method and the second method implements a novel, potentially easier, 3 degrees of freedom pendulum method, which yields the entire inertia tensor from a single swing test. Both methods are using system identification of the pendulum motion to estimate the inertial properties. Substantial corrections (up to 25%) have to be applied to the experimental results. These corrections are caused by the acceleration of the pendulum being immersed in the surrounding air, also called the added mass effect. It has been found that the methods presented in literature to determine the corrections for full-scale aircraft do not give the correct results for the small-scale un-manned aerial vehicle under consideration. The only feasible, cost-effective method to generate these corrections utilise swing tests with a geometrically similar object of known inertial properties. It has also been found that the corrections are unique with respect to the experimental methods. Several benchmarking methods, including the innovative use of static and dynamic wind-tunnel test data, give high confidence in the results.

scholarly journals Tarantula: Design, Modeling, and Kinematic Identification of a Quadruped Wheeled Robot

2018 ◽  
Vol 9 (1) ◽  
pp. 94 ◽  
Author(s):  
Abdullah Aamir Hayat ◽  
Karthikeyan Elangovan ◽  
Mohan Rajesh Elara ◽  
Mullapudi Sai Teja
Keyword(s):  
Cross Sections ◽  
Degrees Of Freedom ◽  
Drainage System ◽  
Cost Effective ◽  
Kinematic Parameters ◽  
Coordinate Measurement ◽  
Cost Effective Method ◽  
Wheeled Robot ◽  
Set Up ◽  
The Cost

This paper firstly presents the design and modeling of a quadruped wheeled robot named Tarantula. It has four legs each having four degrees of freedom with a proximal end attached to the trunk and the wheels for locomotion connected at the distal end. The two legs in the front and two at the back are actuated using two motors which are placed inside the trunk for simultaneous abduction or adduction. It is designed to manually reconfigure its topology as per the cross-sections of the drainage system. The bi-directional suspension system is designed using a single damper to prevent the trunk and inside components from shock. Formulation for kinematics of the wheels that is coupled with the kinematics of each leg is presented. We proposed the cost-effective method which is also an on-site approach to estimate the kinematic parameters and the effective trunk dimension after assembly of the quadruped robot using the monocular camera and ArUco markers instead of high-end devices like a laser tracker or coordinate measurement machine. The measurement technique is evaluated experimentally and the same set up was used for trajectory tracking of the Tarantula. The experimental method for the kinematic identification presented here can be easily extended to the other mobile robots with serial architecture designed legs.

scholarly journals Accurate Measurement of Handwash Quality Using Sensor Armbands: Instrument Validation Study

10.2196/17001 ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. e17001 ◽  
Author(s):  
Chaofan Wang ◽  
Zhanna Sarsenbayeva ◽  
Xiuge Chen ◽  
Tilman Dingler ◽  
Jorge Goncalves ◽  
...  
Keyword(s):  
Health Care ◽  
Hand Hygiene ◽  
Cost Effective ◽  
Video Data ◽  
World Health ◽  
Detection Accuracy ◽  
Cost Effective Method ◽  
Health Care Associated Infections ◽  
Dependent Model ◽  
Health Organization

Background Hand hygiene is a crucial and cost-effective method to prevent health care–associated infections, and in 2009, the World Health Organization (WHO) issued guidelines to encourage and standardize hand hygiene procedures. However, a common challenge in health care settings is low adherence, leading to low handwashing quality. Recent advances in machine learning and wearable sensing have made it possible to accurately measure handwashing quality for the purposes of training, feedback, or accreditation. Objective We measured the accuracy of a sensor armband (Myo armband) in detecting the steps and duration of the WHO procedures for handwashing and handrubbing. Methods We recruited 20 participants (10 females; mean age 26.5 years, SD 3.3). In a semistructured environment, we collected armband data (acceleration, gyroscope, orientation, and surface electromyography data) and video data from each participant during 15 handrub and 15 handwash sessions. We evaluated the detection accuracy for different armband placements, sensor configurations, user-dependent vs user-independent models, and the use of bootstrapping. Results Using a single armband, the accuracy was 96% (SD 0.01) for the user-dependent model and 82% (SD 0.08) for the user-independent model. This increased when using two armbands to 97% (SD 0.01) and 91% (SD 0.04), respectively. Performance increased when the armband was placed on the forearm (user dependent: 97%, SD 0.01; and user independent: 91%, SD 0.04) and decreased when placed on the arm (user dependent: 96%, SD 0.01; and user independent: 80%, SD 0.06). In terms of bootstrapping, user-dependent models can achieve more than 80% accuracy after six training sessions and 90% with 16 sessions. Finally, we found that the combination of accelerometer and gyroscope minimizes power consumption and cost while maximizing performance. Conclusions A sensor armband can be used to measure hand hygiene quality relatively accurately, in terms of both handwashing and handrubbing. The performance is acceptable using a single armband worn in the upper arm but can substantially improve by placing the armband on the forearm or by using two armbands.

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

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