Research on Vibration Model of Special Vehicle Based on Dual-Mass System

2013 ◽  
Vol 385-386 ◽  
pp. 89-92 ◽  
Author(s):  
Ya Jun Shao ◽  
Qin He Gao ◽  
Hong Jie Cheng
Keyword(s):  
Characteristic Curve ◽  
Suspension System ◽  
Mass System ◽  
Nonlinear Characteristics ◽  
Actual Structure ◽  
Vibration Model ◽  
Special Vehicle ◽  
Set Up ◽  
Stiffness And Damping ◽  
The Mathematical Model

Taking a special vehicle vibration system as the research object, according to the actual structure of the chassis, the spring damping and stiffness of the nonlinear characteristics and the tire vertical elastic accounted, a nonlinear vibration model of special vehicle based on dual-mass-system is set up. The tire radial stiffness value is analyzed in Ansys, a simulation is performed by leading the mathematical model of suspension system into Adams, a characteristic curve of stiffness and damping of suspension system is obtained.

Research and Design of In-Arm Torsional Electromagnetic Active Suspension

2019 ◽  
Author(s):  
Chengleng Han ◽  
Lin Xu ◽  
Mohamed A. A. Abdelkareem ◽  
Enkang Cui ◽  
Junyi Zou ◽  
...  
Keyword(s):  
Characteristic Curve ◽  
Body Height ◽  
Active Suspension ◽  
Small Scale ◽  
Unknown Parameters ◽  
Body Attitude ◽  
New Type ◽  
Stiffness And Damping ◽  
The Mathematical Model ◽  
Research And Design

Abstract This paper introduced a new type of an active suspension named as In-Arm Torsional Electromagnetic Active Suspension (ITEAS) according to its suspension characteristics. The proposed ITEAS is capable of actively controlling body attitude and adjusting the stiffness and damping of a suspension system in a larger scale. The structure of the ITEAS system is composing of a mechanical displacement adjustment device, a two-chamber vane damper connected by an electromagnetic valve, two torsion bars and necessary connection units such as trailing arms. Based on the hydraulic theory and fluid mechanics, the mathematical model of the vane damper was established and the external characteristic curve of the damper was obtained through the simulations. Regarding to the ITEAS stiffness and damping analysis, a quarter dynamic vehicle model was established and simulated by the AMESim platform. The results showed that the automobile ride based on the ITEAS system was reasonable as well as the functions of body height adjustment and suspension controllability were available. Thereafter, a small-scale prototype has been built to calibrate the unknown parameters for further research on ITEAS.

Identify Compounds' Target Against Alzheimer's Disease Based on In-Silico Approach

2019 ◽  
Vol 16 (3) ◽  
pp. 193-208 ◽  
Author(s):  
Yan Hu ◽  
Guangya Zhou ◽  
Chi Zhang ◽  
Mengying Zhang ◽  
Qin Chen ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Small Molecule ◽  
Characteristic Curve ◽  
Machine Learning Algorithms ◽  
Learner Model ◽  
Mao B ◽  
Number Of Patients ◽  
Sar Model ◽  
Set Up

Background: Alzheimer's disease swept every corner of the globe and the number of patients worldwide has been rising. At present, there are as many as 30 million people with Alzheimer's disease in the world, and it is expected to exceed 80 million people by 2050. Consequently, the study of Alzheimer’s drugs has become one of the most popular medical topics. Methods: In this study, in order to build a predicting model for Alzheimer’s drugs and targets, the attribute discriminators CfsSubsetEval, ConsistencySubsetEval and FilteredSubsetEval are combined with search methods such as BestFirst, GeneticSearch and Greedystepwise to filter the molecular descriptors. Then the machine learning algorithms such as BayesNet, SVM, KNN and C4.5 are used to construct the 2D-Structure Activity Relationship(2D-SAR) model. Its modeling results are utilized for Receiver Operating Characteristic curve(ROC) analysis. Results: The prediction rates of correctness using Randomforest for AChE, BChE, MAO-B, BACE1, Tau protein and Non-inhibitor are 77.0%, 79.1%, 100.0%, 94.2%, 93.2% and 94.9%, respectively, which are overwhelming as compared to those of BayesNet, BP, SVM, KNN, AdaBoost and C4.5. Conclusion: In this paper, we conclude that Random Forest is the best learner model for the prediction of Alzheimer’s drugs and targets. Besides, we set up an online server to predict whether a small molecule is the inhibitor of Alzheimer's target at http://47.106.158.30:8080/AD/. Furthermore, it can distinguish the target protein of a small molecule.

Research on Dynamic Balance Method of Precision Centrifuge

2014 ◽  
Vol 945-949 ◽  
pp. 777-780
Author(s):  
Tao Liu ◽  
Yong Xu ◽  
Bo Yuan Mao
Keyword(s):  
Mathematical Model ◽  
Balance Control ◽  
Dynamic Balance ◽  
Dynamic Balancing ◽  
Structure Characteristics ◽  
Balance System ◽  
Simulation Results ◽  
Set Up ◽  
System Controller ◽  
The Mathematical Model

Firstly, according to the structure characteristics of precision centrifuge, the mathematical model of its dynamic balancing system was set up, and the dynamic balancing scheme of double test surfaces, double emendation surfaces were established. Then the dynamic balance system controller of precision centrifuge was designed. Simulation results show that the controller designed can completely meet the requirements of precision centrifuge dynamic balance control system.

scholarly journals The use of plasma donor-derived, cell-free DNA to monitor acute rejection after kidney transplantation

2019 ◽  
Vol 35 (4) ◽  
pp. 714-721 ◽  
Author(s):  
Els M Gielis ◽  
Kristien J Ledeganck ◽  
Amélie Dendooven ◽  
Pieter Meysman ◽  
Charlie Beirnaert ◽  
...  
Keyword(s):  
Acute Rejection ◽  
Serum Creatinine ◽  
Characteristic Curve ◽  
Area Under The Curve ◽  
Threshold Value ◽  
Nucleotide Polymorphisms ◽  
Kidney Transplant Recipients ◽  
Cell Free Dna ◽  
Free Dna ◽  
Set Up

Abstract Background After transplantation, cell-free deoxyribonucleic acid (DNA) derived from the donor organ (ddcfDNA) can be detected in the recipient’s circulation. We aimed to investigate the role of plasma ddcfDNA as biomarker for acute kidney rejection. Methods From 107 kidney transplant recipients, plasma samples were collected longitudinally after transplantation (Day 1 to 3 months) within a multicentre set-up. Cell-free DNA from the donor was quantified in plasma as a fraction of the total cell-free DNA by next generation sequencing using a targeted, multiplex polymerase chain reaction-based method for the analysis of single nucleotide polymorphisms. Results Increases of the ddcfDNA% above a threshold value of 0.88% were significantly associated with the occurrence of episodes of acute rejection (P = 0.017), acute tubular necrosis (P = 0.011) and acute pyelonephritis (P = 0.032). A receiver operating characteristic curve analysis revealed an equal area under the curve of the ddcfDNA% and serum creatinine of 0.64 for the diagnosis of acute rejection. Conclusions Although increases in plasma ddcfDNA% are associated with graft injury, plasma ddcfDNA does not outperform the diagnostic capacity of the serum creatinine in the diagnosis of acute rejection.

Dynamic characteristics of squeeze-type mount using magnetorheological fluid

2005 ◽  
Vol 219 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Y K Ahn ◽  
J-Y Ha ◽  
Y-H Kim ◽  
B-S Yang ◽  
M Ahmadian ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Experimental Analysis ◽  
Vibration Isolation ◽  
Dynamic Behaviour ◽  
Electrical Current ◽  
Magnetorheological Fluid ◽  
Test Set ◽  
Mr Fluid ◽  
Set Up ◽  
Stiffness And Damping

This paper presents an analytical and experimental analysis of the characteristics of a squeeze-type magnetorheological (MR) mount which can be used for various vibration isolation areas. The concept of the squeeze-type mount and details of the design of a squeeze-type MR mount are discussed. These are followed by a detailed description of the test set-up for evaluating the dynamic behaviour of the mount. A series of tests was conducted on the prototype mount built for this study, in order to characterize the changes occurring as a result of changing electrical current to the mount. The results of this study show that increasing electrical current to the mount, which increases the yield stress of the MR fluid, will result in an increase in both stiffness and damping of the mount. The results also show that the mount hysteresis increases with increase in current to the MR fluid, causing changes in stiffness and damping at different input frequencies.

Study on the working state of the five hundred-meter aperture spherical telescope using step-wise assignment method

2014 ◽  
Vol 229 (2) ◽  
pp. 316-324 ◽  
Author(s):  
Yu Liu ◽  
Feng Gao
Keyword(s):  
Nonlinear Equations ◽  
Analytical Solutions ◽  
Driving Mechanism ◽  
Initial Value ◽  
Unknown Parameters ◽  
Support Structure ◽  
Assignment Method ◽  
New Type ◽  
Set Up ◽  
The Mathematical Model

The working state of the five hundred-meter aperture spherical telescope (FAST) is solved using the step-wise assignment method. In this paper, the mathematical model of the cable-net support structure of the FAST is set up by the catenary equation. There are a large number of nonlinear equations and unknown parameters of the model. The nonlinear equations are solved by using the step-wise assignment method. The method is using the analytical solutions of the cable-net equations of one working state as the initial value for the next working state, from which the analytical solutions of the nonlinear equations of the cable-net for each working state of the FAST and the tension and length of each driving cable can be obtained. The suggested algorithm is quite practically well suited to study the working state of the cable-net structures of the FAST. Also, the working state analysis result of the cable-net support structure of a reduced model of the cable-net structure reflector for the FAST is given to verify the reliability of the method. In order to show the validity of the method, comparisons with another algorithm to set the initial value are presented. This method has an important guiding significance to the further study on the control of the new type of flexible cable driving mechanism, especially the FAST.

Design of a Damper for a Suspension System via Evolutive Optimization

2013 ◽  
Author(s):  
Carlos A. Duchanoy ◽  
Marco A. Moreno-Armendáriz ◽  
Carlos A. Cruz-Villar
Keyword(s):  
Dynamic Optimization ◽  
Optimization Algorithm ◽  
Physical Characteristics ◽  
Suspension System ◽  
Dynamic Interactions ◽  
Multi Objective ◽  
Damping Coefficients ◽  
Design Variables ◽  
Parameterized Model ◽  
Stiffness And Damping

In this paper a dynamic optimization methodology for designing a passive automotive damper is proposed. The methodology proposes to state the design problem as a dynamic optimization one by considering the nonlinear dynamic interactions between the damper and the other elements of the suspension system, emphasizing geometry, dimensional and movement constraints. In order to obtain realistic simulations of the suspension, a link between a Computer-Aided Engineering Model (CAEM) and a multi-objective dynamic optimization algorithm is developed. As design objectives we consider the vehicle safety and the passenger comfort which are represented by the contact area of the tire and the vibrations of the cockpit respectively. The damper is optimized by stating a set of physical variables that determine the stiffness and damping coefficients as independent variables for the dynamic optimization problem, they include the spring helix diameter, the spring wire diameter, the oil physical characteristics and the bleed orifice diameters among others. The optimization algorithm that we use to solve the problem at hand is a multi-objective evolutive optimization algorithm. For this purpose we developed a parameterized model of the damper which is used to link the CAE tools and the optimization software, thus enabling fitness evaluations during the dynamic optimization process. By selecting the physical characteristics of the damper as design variables instead of the typical stiffness and damping coefficients, it is possible to consider important design constrains as the damper size, movement limitations and anchor points. As result of the proposed methodology a set of blueprints of non dominated Pareto configurations of the damper are provided to the decision maker.

A New CRONE Suspension: More Compact and More Efficient: Part 1—Problematics and Specifications

2009 ◽  
Author(s):  
Audrey Rizzo ◽  
Xavier Moreau ◽  
Alain Oustaloup ◽  
Vincent Hernette
Keyword(s):  
Suspension System ◽  
Technological Structure ◽  
Set Up ◽  
Crone Suspension

This paper presents, in 2 parts, a new CRONE suspension approach. The first part defines the problematics in suspension and gives the different conditions to overcome it. Then in the second paper a new CRONE suspension system is synthesized based on the conclusion of this paper. So, here, is presented how the variations of mass act on the classical suspension and how tools can be set up to simulate the influence of this variation without to choose the technological structure. Then a criterion on the level of wheel holding is established.

scholarly journals SPECIAL VEHICLE MOTION STABILIZATION SYSTEM

2021 ◽  
pp. 37-41
Author(s):  
M. V. Lyashenko ◽  
V. V. Shekhovtsov ◽  
P. V. Potapov ◽  
A. A. Shvedunenko
Keyword(s):  
Pid Controller ◽  
Deflection Angle ◽  
Angular Displacement ◽  
Dynamic Equations ◽  
Engine Torque ◽  
Special Vehicle ◽  
Vehicle Motion ◽  
Motion Stabilization ◽  
The Deflection Angle ◽  
The Mathematical Model

The system of special vehicle (SV) motion stabilization during moving on a straight surface is modeled on the base of dynamic equations of the mathematical model. The movement is stabilized by using a PID controller, the angular displacement of the mass is selected to ensure a given speed of movement, and the deflection angle is stabilized by controlling the engine torque.

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