Low-speed vehicle dynamics and ride quality using controlled D.C. electromagnets

Automatica ◽  
1977 ◽  
Vol 13 (6) ◽  
pp. 605-610 ◽  
Author(s):  
B.V. Jayawant ◽  
P.K. Sinha
Keyword(s):  
Vehicle Dynamics ◽  
Ride Quality ◽  
Low Speed

scholarly journals Design and Experimental Study of Progressive Spring for Formula Student Race Car

2021 ◽  
Author(s):  
Anmol Shripad Patil ◽  
Eshita Nandi ◽  
Prasad Nanasaheb Punekar ◽  
Suyash Wagh
Keyword(s):  
Vehicle Dynamics ◽  
Design Procedure ◽  
Ride Quality ◽  
Linear Rate ◽  
Spring Rate ◽  
Roll Control ◽  
Race Car ◽  
Linear Spring ◽  
Design Calculations ◽  
Major Factors

Abstract The purpose of carrying out the present work is to design, manufacture & test the progressive springs on an FS vehicle. This is one type of helical spring with a variable spring rate. The main purpose of designing progressive springs is to avail all the advantages of the variable spring rate over the linear spring rate and better ride quality along with roll control, compared to linear rate springs. We took several factors of vehicle dynamics under consideration before settling on progressive springs. Before starting with the design procedure, we had set objectives and followed the standard methodology of spring design to get the required output. Along with that, we took design philosophy under consideration. We reviewed all the parameters before finalizing the spring material as it is one of the major factors. We carried out all the necessary design calculations to complete the dimensions and stiffness of the spring. The conclusion helped us to achieve better ride quality and roll control accompanying the optimized spring design satisfying all the necessities such as load, stiffness, and deflection of progressive springs.

scholarly journals Experimental investigation on vibration characteristics of the medium–low-speed maglev vehicle–turnout coupled system

2021 ◽  
Author(s):  
Miao Li ◽  
Dinggang Gao ◽  
Tie Li ◽  
Shihui Luo ◽  
Weihua Ma ◽  
...  
Keyword(s):  
Dynamic Performance ◽  
Field Tests ◽  
Coupled System ◽  
Vibration Characteristics ◽  
Operating Conditions ◽  
Transport Systems ◽  
Ride Quality ◽  
Optimized Design ◽  
Line System ◽  
Low Speed

AbstractThe steel turnout is one of the key components in the medium–low-speed maglev line system. However, the vehicle under active control is prone to vehicle–turnout coupled vibration, and thus, it is necessary to identify the vibration characteristics of this coupled system through field tests. To this end, dynamic performance tests were conducted on a vehicle–turnout coupled system in a medium–low-speed maglev test line. Firstly, the dynamic response data of the coupled system under various operating conditions were obtained. Then, the natural vibration characteristics of the turnout were analysed using the free attenuation method and the finite element method, indicating a good agreement between the simulation results and the measured results; the acceleration response characteristics of the coupled system were analysed in detail, and the ride quality of the vehicle was assessed by Sperling index. Finally, the frequency distribution characteristics of the coupled system were discussed. All these test results could provide references for model validation and optimized design of medium–low-speed maglev transport systems.

Eigenvalue Analysis of Multibody Models of Railroad Vehicles Including Track Flexibility

2011 ◽  
Author(s):  
Jose´ L. Escalona ◽  
Rosario Chamorro ◽  
Antonio M. Recuero
Keyword(s):  
Vehicle Dynamics ◽  
Equations Of Motion ◽  
Steady Motion ◽  
Differential Algebraic Equations ◽  
Eigenvalue Analysis ◽  
Ride Quality ◽  
Algebraic Equations ◽  
Essential Information ◽  
Railroad Vehicles ◽  
The Stability

The stability analysis of railroad vehicles using eigenvalue analysis can provide essential information about the stability of the motion, ride quality or passengers comfort. The system eigenvalues are not in general a vehicle property but a property of a vehicle travelling steadily on a periodic track. Therefore the eigenvalue analysis follows three steps: calculation of steady motion, linearization of the equations of motion and eigenvalue calculation. This paper deals with different numerical methods that can be used for the eigenvalue analysis of multibody models of railroad vehicles that can include deformable tracks. Depending on the degree of nonlinearity of the model, coordinate selection or the coordinate system used for the description of the motion, different methodologies are used in the eigenvalue analysis. A direct eigenvalue analysis is used to analyse the vehicle dynamics from the differential-algebraic equations of motion written in terms of a set of constrained coordinates. In this case not all the obtained eigenvalues are related to the dynamics of the system. As an alternative the equations of motion can be obtained in terms of independent coordinates taking the form of ordinary differential equations. This procedure requires more computations but the interpretation of the results is straightforward.

Description of Methods for the Eigenvalue Analysis of Railroad Vehicles Including Track Flexibility

2012 ◽  
Vol 7 (4) ◽  
Author(s):  
José L. Escalona ◽  
Rosario Chamorro ◽  
Antonio M. Recuero
Keyword(s):  
Vehicle Dynamics ◽  
Equations Of Motion ◽  
Steady Motion ◽  
Differential Algebraic Equations ◽  
Eigenvalue Analysis ◽  
Ride Quality ◽  
Algebraic Equations ◽  
Essential Information ◽  
Railroad Vehicles ◽  
The Stability

The stability analysis of railroad vehicles using eigenvalue analysis can provide essential information about the stability of the motion, ride quality, or passengers’ comfort. The eigenvalue analysis follows three steps: calculation of steady motion, linearization of the equations of motion, and eigenvalue calculation. This paper deals with different numerical methods that can be used for the eigenvalue analysis of multibody models of railroad vehicles that can include deformable tracks. Depending on the degree of nonlinearity of the model and coordinate selection, different methodologies can be used. A direct eigenvalue analysis is used to analyze the vehicle dynamics from the differential-algebraic equations of motion written in terms of a set of constrained coordinates. As an alternative, the equations of motion can be obtained in terms of independent coordinates taking the form of ordinary differential equations. This procedure requires more computations, but the interpretation of the results is straightforward.

Maglev-Girder Interaction for Centralized and De-Centralized Controllers

2010 ◽  
Author(s):  
Thomas Alberts ◽  
Mohamed Aly ◽  
Ashraf Omran
Keyword(s):  
Vehicle Dynamics ◽  
Levitation Force ◽  
Electromagnetic Levitation ◽  
Ride Quality ◽  
Realistic Simulation ◽  
Vehicle Velocity ◽  
Magnetically Levitated

This paper presents a comparison between the centralized and de-centralized controllers of a magnetically levitated vehicle. The simulation accounts for the interaction between the vehicle and girder through the control electromagnetic levitation force of the vehicle. In this way, the effects of: controller dynamics, electrodynamics, vehicle dynamics, and vehicle velocity are considered in order to provide a more realistic simulation. The main purpose of this work is to qualify the performance of each controller in sustaining an acceptable ride quality referred to ISO2631.

New ultrastructural findings about Borrelia burgdorferi by cryofixation, negative staining, thin sectioning and scanning techniques

1990 ◽  
Vol 48 (3) ◽  
pp. 582-583
Author(s):  
S. F. Hayes ◽  
M. D. Corwin ◽  
T. G. Schwan ◽  
D. W. Dorward ◽  
W. Burgdorfer
Keyword(s):  
Lyme Disease ◽  
Borrelia Burgdorferi ◽  
Structural Characterization ◽  
Negative Staining ◽  
Low Speed ◽  
Thin Sectioning ◽  
Ultrastructural Findings

Characterization of Borrelia burgdorferi strains by means of negative staining EM has become an integral part of many studies related to the biology of the Lyme disease organism. However, relying solely upon negative staining to compare new isolates with prototype B31 or other borreliae is often unsatisfactory. To obtain more satisfactory results, we have relied upon a correlative approach encompassing a variety EM techniques, i.e., scanning for topographical features and cryotomy, negative staining and thin sectioning to provide a more complete structural characterization of B. burgdorferi.For characterization, isolates of B. burgdorferi were cultured in BSK II media from which they were removed by low speed centrifugation. The sedimented borrelia were carefully resuspended in stabilizing buffer so as to preserve their features for scanning and negative staining. Alternatively, others were prepared for conventional thin sectioning and for cryotomy using modified procedures. For thin sectioning, the fixative described by Ito, et al.

Some examples of pilot/vehicle dynamics identified from flight test records

1970 ◽  
Author(s):  
Rodney C. Wingrove ◽  
Frederick G. Edwards ◽  
Armando E. Lopez
Keyword(s):  
Vehicle Dynamics ◽  
Flight Test
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