Helicopter Swashplate Design and Analysis Using Semi Compliant Mechanism

2018 ◽  
Author(s):  
Ayse Tekes ◽  
Adeel Khalid ◽  
Niko Giannakakos ◽  
Alexander Bryant
Keyword(s):  
Compliant Mechanism ◽  
High Amplitude ◽  
Plate Motion ◽  
Swash Plate ◽  
Directional Control ◽  
Single Piece ◽  
Model Helicopter ◽  
The Individual ◽  
And Control ◽  
The Mathematical Model

The swashplate of a model helicopter consists of stationary and rotating plates separated by ball bearings. This mechanism enables the swashplate to tilt in all directions and move vertically as one unit. The lower stationary plate is mounted on the main rotor mast and connected to the cyclic and collective controls by a series of pushrods. There are similar pushrods known as pitch links connected to the upper rotating plate. These pitch links are connected to the pitch horns and control the pitch of individual blades. In this study, the pitch links of the model helicopter are replaced by a semi compliant mechanism. This mechanism is directly connected to the pitch horns to control the pitch of the individual blades. The actuation of the bars can be achieved by using high torque stepper or servo motors. These precise low and high amplitude outputs are specifically required for the cyclic and collective controls of the helicopter swashplate. The compliant swashplate mechanism can be fabricated as a single piece using an injection molding technique or by 3D printing. The mechanism is modeled by two similar vector loops in two different planes. The mathematical model of the plate motion and the forces on the mechanism links are developed and simulated using MATLAB and Simulink, and initial results are discussed in this paper. This mechanism would be applied to the helicopter directional control where the plate in the pitch-roll mechanism would serve as the swash plate of the helicopter.

scholarly journals Interactive effects between travel behaviour and COVID-19: a questionnaire study

2021 ◽  
Author(s):  
Jinbao Zhang ◽  
Jaeyoung Lee
Keyword(s):  
Early Stage ◽  
Travel Behaviour ◽  
Interactive Effects ◽  
Factors Affecting ◽  
Individual Level ◽  
Passenger Volume ◽  
Spatial Autoregressive ◽  
Railway Passenger ◽  
The Individual ◽  
And Control

Abstract This study has two main objectives: (i) to analyse the effect of travel characteristics on the spreading of disease, and (ii) to determine the effect of COVID-19 on travel behaviour at the individual level. First, the study analyses the effect of passenger volume and the proportions of different modes of travel on the spread of COVID-19 in the early stage. The developed spatial autoregressive model shows that total passenger volume and proportions of air and railway passenger volumes are positively associated with the cumulative confirmed cases. Second, a questionnaire is analysed to determine changes in travel behaviour after COVID-19. The results indicate that the number of total trips considerably decreased. Public transport usage decreased by 20.5%, while private car usage increased by 6.4%. Then the factors affecting the changes in travel behaviour are analysed by logit models. The findings reveal significant factors, including gender, occupation and travel restriction. It is expected that the findings from this study would be helpful for management and control of traffic during a pandemic.

scholarly journals Medicolegal Causation Investigation of Bacterial Endocarditis Associated with an Oral Surgery Practice Using the INFERENCE Approach

2021 ◽  
Vol 18 (14) ◽  
pp. 7530
Author(s):  
Putri Dianita Ika Meilia ◽  
Maurice P. Zeegers ◽  
Herkutanto ◽  
Michael D. Freeman
Keyword(s):  
Oral Surgery ◽  
Invasive Procedure ◽  
Bacterial Endocarditis ◽  
Infection Prevention And Control ◽  
Healthcare Associated Infection ◽  
Department Of Health ◽  
The Individual ◽  
Healthcare Associated ◽  
And Control ◽  
Causation Analysis

Investigating causation is a primary goal in forensic/legal medicine, aiming to establish the connection between an unlawful/negligent act and an adverse outcome. In malpractice litigation involving a healthcare-associated infection due to a failure of infection prevention and control practices, the medicolegal causal analysis needs to quantify the individual causal probabilities to meet the evidentiary requirements of the court. In this paper, we present the investigation of the most probable cause of bacterial endocarditis in a patient who underwent an invasive procedure at a dental/oral surgical practice where an outbreak of bacterial endocarditis had already been identified by the state Department of Health. We assessed the probability that the patient’s endocarditis was part of the outbreak versus that it was an unrelated sporadic infection using the INFERENCE (Integration of Forensic Epidemiology and the Rigorous Evaluation of Causation Elements) approach to medicolegal causation analysis. This paper describes the step-by-step application of the INFERENCE approach to demonstrate its utility in quantifying the probability of causation. The use of INFERENCE provides the court with an evidence-based, transparent, and reliable guide to determine liability, causation, and damages.

Anti-craving biofeedback program in clinical course of pathological addictions

2017 ◽  
Vol 41 (S1) ◽  
pp. s879-s879
Author(s):  
I. Sosin ◽  
Y. Chuev ◽  
A. Volkov ◽  
O. Goncharova
Keyword(s):  
Individual Preference ◽  
Emotional States ◽  
Digital Information ◽  
External Monitoring ◽  
Computer Testing ◽  
Mode Of Life ◽  
Competing Interest ◽  
The Individual ◽  
Monitoring Module ◽  
And Control

IntroductionModern clinical narcology searches for anti-craving programs to overcome psychoactive substances (PAS) pathological addiction with bio-adaptive regulation of systems (BARS).Aims and objectivesTo develop computer modified biofeedback program integrated with Luscher test.MethodTwenty-two PAS addicts who were undergoing biofeedback modified psycho-training were examined. Computer rheoencephalogram (REG) was used as an external monitoring module.ResultsTechnologically novel biofeedback computer modification was developed with preceding Luscher computer testing for determination of the individual preference colour and the colour producing individual unpleasant associations in respondents. Consequently, biofeedback program was corrected differentially by changing standard colour templates for those personified on monitor. Cerebral hemodynamics condition transferred to individually designed for a particular respondent colour registers is used as a homeostatic parameter reflecting alcohol craving presence/absence: in case of the disordered REG parameters the signal reflects the respondent's unpleasant (negative) colour, and with no craving the screen is filled with positive, pleasant, favourite colour. During BARS auto-training the respondents’ skills to mediate present subjective clinical PAS craving manifestations with unpleasant colour and the experimental auto-training method have been mastered, and those psycho emotional states which displace PAS craving symbolic colour from the screen are selected, and it is substituted with favourite colour (symbol of healthy mode of life motivations).ConclusionsUsage of combined BARS biofeedback improved effectiveness of the training and allowed to objectivize and control the condition of the patient getting reliable visual and digital information about either regress or activation of PAS craving and potential relapse of addictive behaviour.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Controller Parameters Optimization of PWM Converter Based DFIG

2014 ◽  
Vol 672-674 ◽  
pp. 1012-1015
Author(s):  
He Zhu ◽  
Da Tian Xu ◽  
Hao Ran Zhao
Keyword(s):  
Control Strategy ◽  
Simplex Algorithm ◽  
Parameters Optimization ◽  
Pwm Converter ◽  
Stator Flux ◽  
Grid Side ◽  
Rotor Side Converter ◽  
Grid Side Converter ◽  
And Control ◽  
The Mathematical Model

Based on the mathematical model of the PWM converter, control strategy of the grid-side converter directed by the grid voltage and control strategy of the rotor-side converter directed by the stator flux were established combining the vector control theory. The method using the nonlinear simplex algorithm to optimize the PI control parameters of the DFIG unit was first proposed, optimization results proved that this method had good practicality and robustness.

Development of a Ring Permeability Test System

2010 ◽  
Vol 136 ◽  
pp. 153-157
Author(s):  
Yu Hong Du ◽  
Xiu Ming Jiang ◽  
Xiu Ren Li
Keyword(s):  
Control System ◽  
Control Method ◽  
Dynamic Performance ◽  
Experimental Tests ◽  
Measuring Method ◽  
Test System ◽  
Fluid Theory ◽  
And Control ◽  
Relationship Of ◽  
The Mathematical Model

To solve the problem of detecting the permeability of the textile machinery, a dedicated test system has been developed based on the pressure difference measuring method. The established system has a number of advantages including simple, fast and accurate. The mathematical model of influencing factors for permeability is derived based on fluid theory, and the relationship of these parameters is achieved. Further investigations are directed towards the inherent characteristics of the control system. Based on the established model and measuring features, an information fusion based clustering control system is proposed to implement the measurement. Using this mechanical structure, a PID control system and a cluster control system have been developed. Simulation and experimental tests are carried out to examine the performance of the established system. It is noted that the clustering method has a high dynamic performance and control accuracy. This cluster fusion control method has been successfully utilized in powder metallurgy collar permeability testing.

News production theory and practice

Pragmatics ◽  
2008 ◽  
Vol 18 (1) ◽  
pp. 59-85 ◽  
Author(s):  
Tom Van Hout ◽  
Geert Jacobs
Keyword(s):  
Process Analysis ◽  
Theory And Practice ◽  
Computer Assisted ◽  
Press Releases ◽  
News Production ◽  
News Reports ◽  
Business News ◽  
Writing Practices ◽  
The Individual ◽  
And Control

This paper considers notions of agency, interaction and power in business news journalism. In the first part, we present a bird’s eye view of news access theory as it is reflected in selected sociological and anthropological literature on the ethnography of news production. Next, we show how these theoretical notions can be applied to the study of press releases and particularly to the linguistic pragmatic analysis of the specific social and textual practices that surround their transformation into news reports. Drawing on selected fieldwork data collected at the business desk of a major Flemish quality newspaper, we present an innovative methodology combining newsroom ethnography and computer-assisted writing process analysis which documents how a reporter discovers a story, introduces it into the newsroom, writes and reflects on it. In doing so, we put the individual journalist’s writing practices center stage, zoom in on the specific ways in which he interacts with sources and conceptualize power in terms of his dependence on press releases. Following Beeman & Peterson (2001), we argue in favor of a view of journalism as ‘interpretive practice’ and of news production as a process of entextualization involving multiple actors who struggle over authority, ownership and control.

Neurotechnology as a factor of the educational process transformation

2021 ◽  
pp. 98-13
Author(s):  
Л.Д. Александрова ◽  
Р.А. Богачева ◽  
Т.А. Чекалина ◽  
М.В. Максимова ◽  
В.И. Тимонина
Keyword(s):  
Effective Means ◽  
Individual Characteristics ◽  
Educational Process ◽  
Special Equipment ◽  
Research Areas ◽  
Long Time ◽  
Mental Abilities ◽  
The Individual ◽  
And Control

Изучение возможностей мозга для повышения качества обучения находится в центре внимания педагогической науки уже много лет. Развитие цифровизации позволило использовать в исследованиях специальное оборудование, с помощью которого можно оценивать и контролировать работу мозга, развивать умственные способности, познавательные функции и т. п. Нейротехнологии стали эффективным средством, позволяющим трансформировать образовательный процесс за счет подбора специального учебного контента с учетом индивидуальных особенностей обучающихся. Вместе с тем возникает необходимость в конкретизации терминологии и определении актуальных направлений исследований в данной области. For a long time, the study of the brain capabilities for the improvement of the quality of education has been an urgent direction in pedagogical science. Due to the development of digitalization, new areas of research have emerged related to the use of special equipment that makes it possible to assess and control brainwork, develop mental abilities, cognitive functions, etc. One of them is neurotechnology, which is an effective means of transforming the educational process: it offers educational content based on the individual characteristics of students. Thus, a need to concretize the terminology and determine the current research areas arises. The article aims to attempt to fill this gap with the help of a representative analysis of publications on neurotechnologies, as well as the essence of neuroeducation.

Acute Blood Pressure Response to High- and Moderate-Speed Resistance Exercise in Older Adults With Hypertension

2021 ◽  
pp. 1-8
Author(s):  
Carlos Leonardo Figueiredo Machado ◽  
Régis Radaelli ◽  
Clarissa Muller Brusco ◽  
Eduardo Lusa Cadore ◽  
Eurico N. Wilhelm ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Older Adults ◽  
Resistance Exercise ◽  
Blood Pressure Response ◽  
Individual Response ◽  
Older Individuals ◽  
Repetition Maximum ◽  
Control Protocol ◽  
The Individual ◽  
And Control

An increase in blood pressure (BP) occurs during resistance exercise; attention to this response may be necessary in older individuals with hypertension. We compared the BP responses following high- (HSRE) and moderate-speed resistance exercise (MSRE) (4 × 8 repetitions at 60% one-repetition maximum) and control protocol in 15 older adults with hypertension. HSRE and MSRE increased systolic BP (SBP) by the end of each set compared with preexercise and control protocol. Immediately after the fourth set, a higher SBP was observed in MSRE than HSRE (147 ± 14 vs. 141 ± 12 mmHg; p = .01). Taking an exploratory analysis of the individual response, we observed that MSRE resulted in greater mean changes and number of SBP exposures to values ≥150 mmHg (22-fold) than HSRE (10-fold). Diastolic BP increased (p < .05) with exercise, but only MSRE increased compared with the control condition (p < .05). HSRE may be an alternative for individuals in which SBP peak should be avoided.

A prey–predator model and control of a nematodes pest using control in banana: Mathematical modeling and qualitative analysis

2021 ◽  
pp. 2150089
Author(s):  
Sudhakar Yadav ◽  
Vivek Kumar
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Local Stability ◽  
Detection Method ◽  
Initial Release ◽  
Pest Detection ◽  
Predator Model ◽  
And Control ◽  
The Mathematical Model ◽  
Theoretical Results

This study develops a mathematical model for describing the dynamics of the banana-nematodes and its pest detection method to help banana farmers. Two criteria: the mathematical model and the type of nematodes pest control system are discussed. The sensitivity analysis, local stability, global stability, and the dynamic behavior of the mathematical model are performed. Further, we also develop and discuss the optimal control mathematical model. This mathematical model represents various modes of management, including the initial release of infected predators as well as the destroying of nematodes. The theoretical results are shown and verified by numerical simulations.

Study on a global control strategy for rotation speed with different work states in variable-speed constant-frequency wind turbines

2011 ◽  
Vol 225 (7) ◽  
pp. 968-976 ◽  
Author(s):  
G Zheng ◽  
H Xu ◽  
X Wang ◽  
J Zou
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Control Strategy ◽  
Control Strategies ◽  
Stable Operation ◽  
Constant Frequency ◽  
Global Control ◽  
Control Rules ◽  
The Individual ◽  
And Control

This paper studies the operation of wind turbines in terms of three phases: start-up phase, power-generation phase, and shutdown phase. Relationships between the operational phase and control rules for the speed of rotation are derived for each of these phases. Taking into account the characteristics of the control strategies in the different operational phases, a global control strategy is designed to ensure the stable operation of the wind turbine in all phases. The results of simulations are presented that indicate that the proposed algorithm can control the individual phases when considered in isolation and also when they are considered in combination. Thus, a global control strategy for a wind turbine that is based on a single algorithm is presented which could have significant implications on the control and use of wind turbines.

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