Showing 7 results for Azadi
F. Forouzesh, Sh. Azadi,
Volume 1, Issue 1 (IJAE 2011)
Abstract
In this article, rubber bumpers of Double - Wishbone suspension system have been modeled and analyzed. The objective of the present work is to predict the performance of these products during deformation, represent an optimum method to design, obtain stiffness characteristic curves and utilize the results in the automotive suspension dynamic analysis. These parts are nonlinear and exhibit large deformation under loading. They have an important role to limit the motion of wheels and absorb energy. In this study, nonlinear FE model using ABAQUS software was used to obtain the bumper load - displacement curve. Then a laboratory test was done on the bumper to get this curve. The comparison between numerical and experimental results shows a good adaptation. A less than 2 percent difference has been observed between them. Thus, we can use this numerical method to simulate bumpers easily and accurately.
Sh. Azadi, Z. Taherkhani,
Volume 2, Issue 1 (1-2012)
Abstract
This paper develops an automatic parking algorithm based on a fuzzy logic controller with the vehicle pose for the
input and the steering angle for the output. In this way some feasible reference trajectory path have been introduced
according to geometric and kinematic constraints and nonholonomic constraints to simulate motion path of car. Also
a novel method is used for parking space detection according to image processing. A fuzzy controller according to
experiments of skilled driver and path planning is designed, and then fuzzy rules are tuned and finally fuzzy
membership functions are optimized using genetic algorithm. Simulation results illustrate the effectiveness of the
developed schemes
M. Azadi, M. Baloo, G. H. Farrahi, S. M. Mirsalim,
Volume 3, Issue 1 (3-2013)
Abstract
In the present paper, a complete literatures review of thermal barrier coating applications in diesel engines
is performed to select a proper type and to find coating effects. The coating system has effects on the fuel
consumption, the power and the combustion efficiency, pollution contents and the fatigue lifetime of engine
components. Usually there are several beneficial influences by applying ceramic layers on the combustion
chamber, including the piston, the cylinder head, the cylinder block, intake and exhaust valves by using a
plasma thermal spray method. Several disadvantages such as producing nitrogen oxides also exist when a
coating system is used. In this article, all effects, advantages and disadvantages of thermal barrier coatings
are investigated based on presented articles.
A. Jafari, Sh. Azadi, M. Samadian,
Volume 3, Issue 3 (9-2013)
Abstract
The directional response and roll stability characteristics of a partly filled tractor semi-trailer vehicle, with
cylindrical tank, are investigated in various maneuvers. The dynamic interaction of liquid cargo with the
tractor semi-trailer vehicle is also evaluated by integrating a dynamic slosh model of the partly filled tank
with five-degrees-of-freedom of a tractor semi-trailer tank model. The dynamic fluid slosh within the tank
is modeled using three-dimensional Navier-Stokes equations, coupled with volume-of-fluid equations and
analysed using the FLUENT software. The coupled tank-vehicle model is subsequently analysed to
determine the roll stability characteristics for different maneuvers. The results showed the interaction of
fluid slosh with vehicle's dynamic. Another findings of this investigation also revealed that the roll stability
of a tractor semi-trailer tank carrying liquid was highly affected by fluid sloshing and caused degradation of
roll stability in comparison with vehicle carrying rigid cargo.
S. A. Milani, S. Azadi,
Volume 4, Issue 4 (12-2014)
Abstract
Nowadays, the use of small vehicles is spreading among urban areas and one sort of these vehicles are three-wheeled vehicles (TWVs) which can be competitive with four-wheeled urban vehicles (FWVs) in aspects such as smallness, simple manufacturing, and low tire rolling resistance, fuel consumption and so on. The most critical instability associated with TWVs is the roll over. In this paper a tilt control mechanism has been modeled which can reduce the danger of roll over by leaning the vehicle towards the turning center in order to decrease the amount of lateral load transfer (LLT), and by doing so, system combines the dynamical abilities of a passenger car with a motorcycle. A 3 degree of freedom vehicle model is simulated at constant speed in MATLAB-Simulink environment and a fuzzy algorithm is developed to control such a non-linear system with appropriate tilting torque. Results are interpreted in presence and absence of controller with different longitudinal speeds and steering inputs the results are also compared to behavior of a similar FWV and this is concluded that the tilt control system could countervail deficiencies of the TWV compared to the FWV.
R. Hosseini, M. Azadi, , , ,
Volume 5, Issue 4 (12-2015)
Abstract
In the present paper, the modal analysis on a full finite element model of an off-road vehicle. This vehicle was modeled in the CATIA software and then meshed in the HYPERMESH software. The free vibration analysis was conducted by the ABAQUS software. By applying an external displacement, the forced vibration analysis was also performed. As a result, natural frequencies and shape modes were extracted to detect critical regions. Then, some improvements were suggested to have better vibration behavior of the vehicle.
Mr. Hamid Rahmanei, Dr. Abbas Aliabadi, Prof. Ali Ghaffari, Prof. Shahram Azadi,
Volume 13, Issue 2 (6-2023)
Abstract
The coordinated control of autonomous electric vehicles with in-wheel motors is classified as over-actuated control problems requiring a precise control allocation strategy. This paper addresses the trajectory tracking problem of autonomous electric vehicles equipped with four independent in-wheel motors and active front steering. Unlike other available methods presenting optimization formulation to handle the redundancy, in this paper, the constraints have been applied directly using the kinematic relations of each wheel. Four separate sliding mode controllers are designed in such a way that they ensure the convergence of tracking errors, in addition to incorporating the parametric and modeling uncertainties. The lateral controller is also designed to determine the front steering angles to eliminate lateral tracking errors. To appraise the performance of the proposed control strategy, a co-simulation is carried out in MATLAB/Simulink and Carsim software. The results show that the proposed control strategy has enabled the vehicle to follow the reference path and has converged the errors of longitudinal and lateral positions, velocity, heading angle, and yaw rate. Furthermore, the proposed control system shows promising results in the presence of uncertainties including the mass and moment of inertia, friction coefficient, and the wind disturbances.