Experimental Identification of a Motorcycle Rider 3D Movements on a Running Vehicle

2006 ◽  
Author(s):  
M. Bocciolone ◽  
F. Cheli ◽  
E. Leo ◽  
M. Pezzola
Keyword(s):  
Numerical Model ◽  
Voltage Divider ◽  
Dynamical Behaviour ◽  
The Body ◽  
Experimental Session ◽  
System A ◽  
Race Track ◽  
Motorcycle Rider ◽  
Multi Body ◽  
Divider Type

The aim of the research is to identify the movements of a race motorcycle rider while running on a race track. It is well known how the inertial characteristics of human body are comparable to the motorcycle ones. It is necessary to understand the body-vehicle interactions to describe the dynamical behaviour of the complete system. A numerical model of pilot-vehicle system, in a multi body logic, is being developed, using the results of this research. The tested motorcycle is equipped by a fixed original measurements system, characterised by five cable-extension position transducer (voltage divider type). The pilot’s back is equipped by a rigid ergal staff, constrained by a multi cross belts system, on which two target points are placed, with pre defined distance. These targets are pointed by the five sensors. Through the use of a non linear numerical model it is possible to identify the translational and the cardanic rotational 3D movements of the rider body. To proceed with the procedure validation and calibration, an anthropomorphic arm robot was used. The targets staff was constrained on the end effector, the sensors system was ground fixed and incremental displacements and rotations were programmed. Some results finally obtained in a first experimental session are reported.

An ayurvedic tablet formulation for ulcer protection

2020 ◽  
Vol 10 (4) ◽  
pp. 35-38
Author(s):  
Shiva Kumar K ◽  
Purushothaman M ◽  
Soujanya H ◽  
Jagadeeshwari S
Keyword(s):  
Pharmacological Activity ◽  
The Body ◽  
Gastric Ulcers ◽  
Antiulcer Activity ◽  
Herbal Drugs ◽  
Human Beings ◽  
Synthetic Drugs ◽  
Scientific Investigations ◽  
System A ◽  
The World

Gastric ulcers or the peptic ulcer is the primary disease that affects the gastrointestinal system. A large extent of the population in the world are suffering from the disease, and the age group of people those who suffer from ulcers are 20-55years. Herbs are known to the human beings that are useful in the treatment of diseases, and there are a lot of scientific investigations that prove the pharmacological activity of herbal drugs. Practitioners have been using the herbal material to treat the ulcers successfully, and the same had been reported scientifically. Numerous publications have been made that proves the antiulcer activity of the plants around the world. The tablets were investigated for the antiulcer activity in two doses 200 and 400mg/kg in albino Wistar rats in the artificial ulcer those are induced by the ethanol. The prepared tablets showed a better activity compared to the standard synthetic drug and the marketed ayurvedic formulation. The tablets showed a dose-dependent activity in ulcer prevention and treatment. Many synthetic drugs are available for the ulcer treatment, and the drugs pose the other problems in the body by showing the side effects and some other reactions. This limits the use of synthetic drugs to treat ulcers effectively. Herbs are known to the human beings that are useful in the treatment of diseases, and there are a lot of scientific investigations that prove the pharmacological activity of herbal drugs.

scholarly journals Zur exakten Behandlung von kollektiven Rotationen Teil A: Theorie / On the Exact Treatment of Collective Rotations Part A: Theory

1973 ◽  
Vol 28 (2) ◽  
pp. 206-215
Author(s):  
Hanns Ruder
Keyword(s):  
Coordinate System ◽  
Perturbation Expansion ◽  
Rotational Energy ◽  
The Body ◽  
System A ◽  
N Body Problem ◽  
Definition Of ◽  
Fixed System ◽  
Body Fixed Coordinate System ◽  
Groundstate Energy

Basic in the treatment of collective rotations is the definition of a body-fixed coordinate system. A kinematical method is derived to obtain the Hamiltonian of a n-body problem for a given definition of the body-fixed system. From this exact Hamiltonian, a consequent perturbation expansion in terms of the total angular momentum leads to two exact expressions: one for the collective rotational energy which has to be added to the groundstate energy in this order of perturbation and a second one for the effective inertia tensor in the groundstate. The discussion of these results leads to two criteria how to define the best body-fixed coordinate system, namely a differential equation and a variational principle. The equivalence of both is shown.

Development of the Meridian-Visualizing System that Superimposes a Bio-signal upon a Body Image

2004 ◽  
Vol 32 (04) ◽  
pp. 631-640
Author(s):  
Dong-Myong Jeong ◽  
Yong-Heum Lee ◽  
Myeong Soo Lee
Keyword(s):  
Body Image ◽  
Skin Resistance ◽  
The Body ◽  
Acupuncture Points ◽  
Identification System ◽  
Electrode Position ◽  
Excitation Current ◽  
System A ◽  
Dc Excitation ◽  
Single Power

The precise selection and the identification of acupuncture points are essential for the diagnosis and treatment of patients in Oriental medicine. In this study, we have developed a meridian identification system using Single-Power Alternating Current (SPAC), which discriminates between true acupoints and non-acupoints. The SPAC system is not affected by skin resistance or pressure and is more accurate than the existing meridian location system, which uses direct current (DC) excitation current. The accuracy of the meridian location is ensured with the SPAC system because it has the highest sensitivity and the lowest effect on the human body. A microprocessor is used to enhance reliability and increase the accuracy of the SPAC measurements. Current distribution is displayed using an image that overlays the measured skin current on the body image. The positions of the acupoints are then displayed on the body image. This method visualizes the meridian by measuring skin current with an improved electrode using the acupoint discrimination system. A computer display shows the transmitted current as a color related to the electrode position. We demonstrated that by changing the point of measurement on the skin and tracing the electrode on the screen, it is possible to visualize acupoints and meridian phenomena using the color display.

A Developed Numerical Method for Turbulent Unsteady Fluid Flow in Two-Phase Systems with Moving Interface

2017 ◽  
Vol 14 (06) ◽  
pp. 1750063 ◽  
Author(s):  
A. M. Hegab ◽  
S. A. Gutub ◽  
A. Balabel
Keyword(s):  
Numerical Model ◽  
Gas Phase ◽  
Level Set ◽  
The Body ◽  
Phase System ◽  
Computational Domain ◽  
Two Phase ◽  
Moving Interface ◽  
Level Set Function ◽  
Gas System

This paper presents the development of an accurate and robust numerical modeling of instability of an interface separating two-phase system, such as liquid–gas and/or solid–gas systems. The instability of the interface can be refereed to the buoyancy and capillary effects in liquid–gas system. The governing unsteady Navier–Stokes along with the stress balance and kinematic conditions at the interface are solved separately in each fluid using the finite-volume approach for the liquid–gas system and the Hamilton–Jacobi equation for the solid–gas phase. The developed numerical model represents the surface and the body forces as boundary value conditions on the interface. The adapted approaches enable accurate modeling of fluid flows driven by either body or surface forces. The moving interface is tracked and captured using the level set function that initially defined for both fluids in the computational domain. To asses the developed numerical model and its versatility, a selection of different unsteady test cases including oscillation of a capillary wave, sloshing in a rectangular tank, the broken-dam problem involving different density fluids, simulation of air/water flow, and finally the moving interface between the solid and gas phases of solid rocket propellant combustion were examined. The latter case model allowed for the complete coupling between the gas-phase physics, the condensed-phase physics, and the unsteady nonuniform regression of either liquid or the propellant solid surfaces. The propagation of the unsteady nonplanar regression surface is described, using the Essentially-Non-Oscillatory (ENO) scheme with the aid of the level set strategy. The computational results demonstrate a remarkable capability of the developed numerical model to predict the dynamical characteristics of the liquid–gas and solid–gas flows, which is of great importance in many civilian and military industrial and engineering applications.

scholarly journals Model-Based Optimization of Velocity Strategy for Lightweight Electric Racing Cars

2018 ◽  
Vol 2018 ◽  
pp. 1-20 ◽  
Author(s):  
Mirosław Targosz ◽  
Wojciech Skarka ◽  
Piotr Przystałka
Keyword(s):  
Numerical Model ◽  
Energy Efficient ◽  
Atmospheric Conditions ◽  
Vehicle Model ◽  
Model Based ◽  
Race Track ◽  
Functional Features ◽  
Race Conditions ◽  
Vehicle Dynamic Model ◽  
And Control

The article presents a method for optimizing driving strategies aimed at minimizing energy consumption while driving. The method was developed for the needs of an electric powered racing vehicle built for the purposes of the Shell Eco-marathon (SEM), the most famous and largest race of energy efficient vehicles. Model-based optimization was used to determine the driving strategy. The numerical model was elaborated in Simulink environment, which includes both the electric vehicle model and the environment, i.e., the race track as well as the vehicle environment and the atmospheric conditions. The vehicle model itself includes vehicle dynamic model, numerical model describing issues concerning resistance of rolling tire, resistance of the propulsion system, aerodynamic phenomena, model of the electric motor, and control system. For the purpose of identifying design and functional features of individual subassemblies and components, numerical and stand tests were carried out. The model itself was tested on the research tracks to tune the model and determine the calculation parameters. The evolutionary algorithms, which are available in the MATLAB Global Optimization Toolbox, were used for optimization. In the race conditions, the model was verified during SEM races in Rotterdam where the race vehicle scored the result consistent with the results of simulation calculations. In the following years, the experience gathered by the team gave us the vice Championship in the SEM 2016 in London.

Some Observations of Chaotic Vibration Phenomena in High-Speed Rotordynamics

1991 ◽  
Vol 113 (1) ◽  
pp. 50-57 ◽  
Author(s):  
F. F. Ehrich
Keyword(s):  
Numerical Model ◽  
High Speed ◽  
Chaotic Behavior ◽  
Narrow Region ◽  
System A ◽  
Vibratory Response ◽  
Local Contact ◽  
Jeffcott Rotor ◽  
Subharmonic Response ◽  
Static Part

Subharmonic response in rotordynamics may be encountered when a rotor is operated with its rotational centerline eccentric to that of a close clearance static part, so that local contact can take place during each orbit when the rotor is excited by residual unbalance. The rotor will tend to bounce at or near its fundamental frequency when the rotor is operated at or near a speed which is a whole number [n] times that frequency. Using a simple numerical model of a Jeffcott rotor mounted on a nonlinear spring, it is found that the vibratory response in the transition zone midway between adjacent zones of subharmonic response has all the characteristics of chaotic behavior. The transition from subharmonic to chaotic response has a complex substructure which involves a sequence of bifurcations of the orbit with variations in speed. This class of rotordynamic behavior was confirmed and illustrated by experimental observations of the vibratory response of a high-speed turbomachine, operating at a speed between 8 and 9 times its fundamental rotor frequency when in local contact across a clearance in the support system. A narrow region between zones of 8th order and 9th order subharmonic response was identified where the response had all the characteristics of the chaotic motion identified in the numerical model.

Finding the jerk properties of multi-body systems using helicoidal vector fields

2008 ◽  
Vol 222 (11) ◽  
pp. 2217-2229 ◽  
Author(s):  
J Gallardo-Alvarado ◽  
H Orozco-Mendoza ◽  
R Rodríguez-Castro
Keyword(s):  
Reference Frame ◽  
Vector Fields ◽  
Time Derivative ◽  
The Body ◽  
Body System ◽  
Third Order ◽  
Numerical Examples ◽  
Multi Body

In this contribution, the kinematic angular and linear third-order properties, also known as jerk analysis, of a multi-body system are determined applying the concept of helicoidal vector fields. The reduced acceleration state, or accelerator, of the body of interest, with respect to a reference frame, is obtained as the time derivative, via a helicoidal field, of the velocity state, also known as the infinitesimal twist. Following that trend, the reduced jerk state, or jerkor, is obtained as the time derivative of the accelerator. The computation of the instantaneous centre of jerk, with its corresponding ellipsoid of jerk, is also included. The expressions thus obtained are extended systematically to multi-body systems. Two numerical examples are provided in order to illustrate the potential of the presented method.

Double Closed-Loop Motor Modeling and Analysis for Lunar Rover Simulation

2012 ◽  
Vol 472-475 ◽  
pp. 1971-1976 ◽  
Author(s):  
Wei Dong Huang ◽  
Hong Kui Feng ◽  
Jin Song Bao ◽  
You Sheng Xu
Keyword(s):  
Pid Control ◽  
Control Algorithm ◽  
Dynamics Simulation ◽  
Motor Drive ◽  
Modeling And Analysis ◽  
Lunar Rover ◽  
System A ◽  
Drive Control ◽  
Body Dynamics ◽  
Multi Body

Motor drive control is the major study field in the development of lunar rover. Based on the double-closed DC loop adjustable-speed system, a motor drive simulation module using a position recursive PID control algorithm is developed, which is integrated into the multi-body dynamics simulation system, to carry out the whole lunar rover simulation. And the cruise process of lunar rover locomotion in the complex lunar terrain is simulated in a virtual environment.

Numerical Towing Model for LNG Carrier Approach in Exposed Environment Calibrated With Full-Scale Measurements and Operability Criterion

2021 ◽  
Author(s):  
Erwan Auburtin ◽  
Quentin Delivré ◽  
Jason McConochie ◽  
Jim Brown ◽  
Yuriy Drobyshevski
Keyword(s):  
Numerical Model ◽  
Degrees Of Freedom ◽  
Line Tension ◽  
Full Scale ◽  
Model Parameters ◽  
Wave Loads ◽  
Simplified Approach ◽  
Large Matrix ◽  
Multi Body ◽  
The Impact

Abstract The Prelude Floating Liquefied Natural Gas (FLNG) platform is designed to offload liquefied natural and petroleum gas products to carrier vessels moored in a Side-by-Side (SBS) configuration. Prior to the mooring operation, the carrier vessel is escorted and held alongside the FLNG with the assistance of tugs connected to her bow and stern to ensure sufficient control over the vessel in this critical phase. In order to better understand the impact of environmental conditions, to determine the optimum length, strength, material and configuration of the towline stretcher, and to estimate the maximum operable environments, coupled multi-body simulations have been performed in time domain. The numerical model, which considered both the LNG carrier and the forward tug, was calibrated using full-scale measurements of tug motions and tow line tension recorded during a real approach and berthing manoeuvre at Prelude FLNG. The measured environment effects were generated numerically and the model parameters were adjusted to reproduce the recorded behavior as accurately as possible. Since actions of the tug master are difficult to model numerically and only the statistical environment parameters are known, a simplified approach has been adopted for modelling the tug propulsion and steering using a combination of static forces, stiffness and linear and quadratic damping for relevant horizontal degrees of freedom. The calibrated numerical model was first subjected to several sensitivity assessments of the modelling level (single- or multi-body, inclusion of second-order wave loads, inclusion of forward speed). Then sensitivity studies were performed to help address operational requirements related to the wave height and direction, and the stretcher length and strength. The conclusions have been taken into consideration for the selection of the tow line configurations for future operations. Finally, the calibrated coupled LNG carrier and tug model was used to derive Prelude-specific tug operability criteria that may be used for decision-making based on weather forecasts, prior to the SBS offloading operations. A large matrix of swell and wind driven waves was simulated over a range of wave heights, periods, directions and static towing forces to allow a criterion to be developed based on a stochastic extreme tow line tension. Such criterion considers relevant wave parameters while remaining simplified enough for easy use in operations. This paper describes the assumptions and process to numerically model the towing configuration and calibrate the different coefficients, discusses the results obtained for the various sensitivities, and explains the operability criteria. Important conclusions and lessons learnt are also shared.

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