scholarly journals Tail-Actuator Propulsion Device for Aquatic Robot

2006 ◽  
Vol 18 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Andrea Manuello Bertetto ◽  
◽  
Maurizio Ruggiu
Keyword(s):  
Mathematical Model ◽  
Numerical Procedure ◽  
Numerical Data ◽  
Operating Principle ◽  
The Other ◽  
Kinematics And Dynamics ◽  
Experimental Characterization ◽  
Fish Propulsion ◽  
Geometrical Dimensions ◽  
Simplified Mathematical Model

In this paper an aquatic device inspired to the fish propulsion is proposed. At the first, the operating principle of the fluidic actuator and its experimental characterization are presented. Then, the results of numerous tests carried out on the integrated tail-actuator device are shown either in terms of thrust exerted or as biomorphism of its kinematics. The tests were run at several driven frequencies with different fins depending on their geometrical dimensions and compliances. On the other hand, a simplified mathematical model of the propulsion system, based on the calculation of the instantaneous tail kinematics and dynamics by means of a numerical procedure, is proposed with the aim of simulating performances either in terms of thrust exerted or kinematics behavior. Finally a discussion about the results obtained and a comparison between experimental and numerical data are presented.

scholarly journals Indicators of Violence Levels: Questionnaires and Predictive Mathematical Model

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
E. Leal-Enríquez ◽  
A. R. Gutiérrez-Antúnez
Keyword(s):  
Mathematical Model ◽  
Partner Violence ◽  
Numerical Procedure ◽  
Numerical Data ◽  
Intimate Partner ◽  
Loss Of Control ◽  
Victim Assistance ◽  
Key Factor ◽  
The Mathematical Model ◽  
Health Experts

In this paper, we present, in detail, how a mathematical model that simulates the probable scenarios of intimate partner violence is linked to the application of any questionnaire of domestic violence already in use. This questionnaire assigns a weight of severity to each proposed inquiry for the types of psychological, physical, and sexual violence. We show a numerical procedure that must be performed to obtain the probable scenarios of violence in which the victim is involved, taking as key factor the loss of control of the perpetrator. With the numerical data obtained from the application of the mathematical model, the probable levels of violence that the victim could experience month to month for two cycles of violence are plotted, as well as the behaviors of the probable states of loss of control that the perpetrator would have during the next twelve months. Based on the results obtained, we generated a help table of indicators that could be used by victim assistance centers and/or health experts for decision-making schemes.

scholarly journals Analysis and Forecast of novel Coronavirus (Covid-19) Cases in India: A Simplified Mathematical Model based on Growth and Recovery

2020 ◽  
Author(s):  
R R Rajalaxmi ◽  
Chockalingam Aravind Vaithilingam ◽  
Gayathri Sivasubramanian ◽  
Lalitha R
Keyword(s):  
Mathematical Model ◽  
Reference Data ◽  
Epidemiological Data ◽  
The Other ◽  
Disease Spread ◽  
Epidemic Spreading ◽  
Effective Measure ◽  
Model Predictions ◽  
Novel Coronavirus ◽  
Simplified Mathematical Model

This work analyses the different phases of Covid-19 outbreak in India and performs progress of the disease spread. The data is collected from John Hopkins epidemiological data providing the latest data from January 31,2020 to May 31, 2020. A simple mathematical model is developed to gather a quantitative picture of the epidemic spreading with limited reference data. Further, we performed an analysis and forecast of the disease spread in different phases of lock down in the country. The profound model predictions considering the overall data exhibit that the numbers to reach peak between 28 August 2020 to 6 Sep 2020. As the pandemic still increases the number of infected cases, different quarantine levels would serve as an effective measure in containing the spread much earlier than the other similar cases.

Modelling of Steam Cracking. I. Simplified Mathematical Model of Steam Cracking Furnace and Its Identification

1993 ◽  
Vol 58 (5) ◽  
pp. 1042-1054
Author(s):  
Josef Horák ◽  
Zdeněk Bělohlav
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Convective Heat Transfer Coefficient ◽  
Numerical Procedure ◽  
Sources Of Information ◽  
Single Input Single Output ◽  
Steam Cracking ◽  
Simplified Mathematical Model

A simplified mathematical model of a steam cracking furnace was constructed. The model involves adjustable parameters, values of which are to be evaluated on the basis of measurements available in industrial reactors. The following adjustable parameters are considered: the effective radiative heat transfer coefficient, the convective heat transfer coefficient, the mean relative reactivity of the reaction mixture. The sources of information which can be utilized in the model identification are discussed. A numerical procedure was developed for finding the best set of the adjustable parameters. The procedure is based on the analogy with single-input single-output control loops.

Modeling of an Elastic Fin Micromotor

2000 ◽  
Author(s):  
P. Lu ◽  
K. H. Lee ◽  
S. P. Lim ◽  
S. Dong ◽  
W. Z. Lin
Keyword(s):  
Mathematical Model ◽  
Operating Principle ◽  
Motion Equations ◽  
Numerical Examples ◽  
Initial Effort ◽  
Dynamical Deformation ◽  
Validity Range ◽  
Simplified Mathematical Model

Abstract In the present work, a simplified mathematical model of ultrasonic elastic fin micromotors has been developed. According to the operating principle of this type of motors, motions of rotor in each cycle of stator vibration are divided into several stages based on whether the fin tip and the stator is in contact with slip, contact without slip or separation, respectively. The motion equations of the rotor in each stage are established and derived. The validity range of the model has been discussed through numerical examples. This work provides an initial effort to construct a model for the elastic fin motor by considering dynamical deformation of the rotor as well as intermittent contacts.

scholarly journals Analysis and Forecast of novel Coronavirus (Covid-19) Cases in India: A Simplified Mathematical Model based on Growth and Recovery

2020 ◽  
Author(s):  
R R Rajalaxmi ◽  
Chockalingam Aravind Vaithilingam ◽  
Gayathri Sivasubramanian ◽  
Lalitha R
Keyword(s):  
Mathematical Model ◽  
Reference Data ◽  
Epidemiological Data ◽  
The Other ◽  
Disease Spread ◽  
Epidemic Spreading ◽  
Effective Measure ◽  
Model Predictions ◽  
Novel Coronavirus ◽  
Simplified Mathematical Model

This work analyses the different phases of Covid-19 outbreak in India and performs progress of the disease spread. The data is collected from John Hopkins epidemiological data providing the latest data from January 31,2020 to May 31, 2020. A simple mathematical model is developed to gather a quantitative picture of the epidemic spreading with limited reference data. Further, we performed an analysis and forecast of the disease spread in different phases of lock down in the country. The profound model predictions considering the overall data exhibit that the numbers to reach peak between 28 August 2020 to 6 Sep 2020. As the pandemic still increases the number of infected cases, different quarantine levels would serve as an effective measure in containing the spread much earlier than the other similar cases.

A novel bi-directional deformable fluid actuator

2014 ◽  
Vol 228 (15) ◽  
pp. 2799-2809 ◽  
Author(s):  
Carlo Ferraresi ◽  
Walter Franco ◽  
Giuseppe Quaglia
Keyword(s):  
Mathematical Model ◽  
Internal Structure ◽  
Operating Principle ◽  
Original Shape ◽  
Pneumatic Muscles ◽  
Tensile Forces ◽  
Modelling Methodology ◽  
The Mathematical Model ◽  
Geometrical Dimensions ◽  
Different Levels

The deformable fluid actuators available on the market, i.e. pneumatic muscles and pneumatic springs, are designed to mainly exert compressive or tensile forces. This paper deals with a novel fluid deformable actuator, with three membranes, called BiFAc3, whose particular feature is the ability to exert both tensile and compressive forces. The structure of the actuator is based on three cylindrical coaxial nonisotropic membranes connected to two end plates, whose original shape allows the independent supply of the three internal chambers. The first part of the paper deals with the internal structure and the geometry of the actuator, describes the operating principle and presents a prototype. The second part presents a modelling methodology that can be used to design and analyse the actuator in dynamic applications. The mathematical model of the actuator is based on three different levels of complexity which correspond to three consecutive design stages. The model has been experimentally validated: it is a useful tool for the choice of the actuator’s geometrical dimensions, in order to satisfy specific applicative requirements.

The Numerical Analysis of the Velocity and Pressure Distribution of the Oil Film in Heavy Hydrostatic Thrust Bearing

2014 ◽  
Vol 541-542 ◽  
pp. 658-662
Author(s):  
Jian Li ◽  
Yuan Chen ◽  
Yang Chun Yu ◽  
Zhu Xin Tian ◽  
Yu Huang
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Pressure Distribution ◽  
Working Conditions ◽  
Thrust Bearing ◽  
Rotation Speed ◽  
The Other ◽  
Surface Load ◽  
Oil Film ◽  
Volume Method

To study the velocity and pressure distribution of the oil film in a heavy hydrostatic thrust bearing, a mathematical model of the velocity is proposed and the finite volume method (FVM) has been used to simulate the flow field under different working conditions. Some pressure experiments were carried out and the results verified the correctness of the simulation. It is concluded that the pressure distribution varies small under different rotation speed when the surface load on the workbench is constant. But the velocity of the oil film is influenced greatly by the rotation speed. When the rotation speed of the workbench is as quick as enough, the velocity of the oil film on one radial side of the pad will be zero, that is to say the lubrication oil will be drained from the other three sides of the recess.

scholarly journals Development and Evaluation of the Traction Characteristics of a Crawler EOD Robot

2021 ◽  
Vol 11 (9) ◽  
pp. 3757
Author(s):  
Lucian Ștefăniță Grigore ◽  
Ionica Oncioiu ◽  
Iustin Priescu ◽  
Daniela Joița
Keyword(s):  
The Other ◽  
Kinematics And Dynamics ◽  
The Novel ◽  
Propulsion Systems ◽  
Load Bearing ◽  
Emergency Situations ◽  
Modular Model ◽  
Explosive Ordnance Disposal ◽  
Multiple Missions ◽  
A Company

Today, terrestrial robots are used in a multitude of fields and for performing multiple missions. This paper introduces the novel development of a family of crawling terrestrial robots capable of changing very quickly depending on the missions they have to perform. The principle of novelty is the use of a load-bearing platform consisting of two independent propulsion systems. The operational platform, which handles the actual mission, is attached (plug and play) between the two crawler propulsion systems. The source of inspiration is the fact that there are a multitude of intervention robots in emergency situations, each independent of the other. In addition to these costs, there are also problems with the specialization of a very large number of staff. The present study focused on the realization of a simplified, modular model of the kinematics and dynamics of the crawler robot, so that it can be easily integrated, by adding or removing the calculation modules, into the software used. The designed model was integrated on a company controller, which allowed us to compare the results obtained by simulation with those obtained experimentally. We appreciate that the analyzed Explosive Ordnance Disposal (EOD) robot solution represents a premise for the development of a family of EOD robots that use the same carrier platform and to which a multitude of operational platforms should be attached, depending on the missions to be performed.

Dynamic Analysis on a Cable-Driven Interventional Active Catheter Using Kane's Method Combined with Screw Theory

2014 ◽  
Vol 527 ◽  
pp. 140-145
Author(s):  
Da Xu Zhao ◽  
Bai Chen ◽  
Guo Zhong Shou ◽  
Yu Qi Gu
Keyword(s):  
Mathematical Model ◽  
Dynamic Analysis ◽  
Motion Control ◽  
Screw Theory ◽  
Driving Forces ◽  
Structure Design ◽  
Kinematics And Dynamics ◽  
Existing Problems ◽  
Blind Area ◽  
The Mathematical Model

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.

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