Articolele autorului Catalin Alexandru
Link la profilul stiintific al lui Catalin Alexandru

Method for the quasi-static analysis of beam axle suspension systems used for road vehicles
Method for the multi-criteria optimization of car wheel suspension mechanisms. Ingeniería e Investigación, vol. 36, nr. 2, August 2016, p. 60-67, ISSN 0120-5609, DOI 10.15446/ing.investig.v36n2.52517

The paper deals with a general method for the multi-criteria optimization of the rear wheels suspension mechanisms in terms of kinematic behavior. The suspension mechanism is decomposed in basic binary links, and the kinematic synthesis is separately performed for each of them. The design variables are the global coordinates of the joint locations on the car body (chassis). The disposing of the joints on the wheel carrier were exclusively established

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A comparative analysis between the tracking solutions implemented on a photovoltaic string

The paper deals with a comparative analysis (in terms of energetic efficiency) between the mono-axis and dual-axis tracking solutions implemented on a photovoltaic (PV) string. The study reveals which solution is more efficient in the geographical area of Braşov, and under which conditions. The tracking efficiencies of the mono-axis and dual-axis systems are compared considering two orientation programs: seasonal and annual. Taking into account

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Modelling the angular capability of the ball joints in a complex mechanism with two degrees of mobility

The paper puts forward a complex linkage mechanism with two degrees of mobility and three kinematic loops, which is used for the guiding (suspension and steering) system of the vehicles. The geometric parameters and the coordinates frames that define the mechanical system are presented, as well as the specific kinematic functions. For this complex mechanical system, the angular capability of the ball (spherical) joints is defined by two angles. The

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A novel open-loop tracking strategy for photovoltaic systems

This paper approaches a dual-axis tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. This is an equatorial tracking system, with two DC motors that drive speed reducer worm gears. The innovative aspect in the control system design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with

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Optimal design of the solar tracker used for a photovoltaic string
Design and simulation of a steering gearbox with variable transmission ratio
Optimal algorithm for spray pyrolysis deposition of TiO2 films by using an industrial robot

This paper approaches the optimization of the spray pyrolysis deposition (SPD) using an industrial robot. The purpose is to develop an optimal algorithm for obtaining uniform films on a planar surface. The design objective refers to the uniformity of the film, the aim being to optimize the difference in thickness between two specific points on the sample. The characteristic parameters of the SPD process (the substrate temperature, the height of spraying

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Dynamic optimization of the tracking system for a pseudo-azimuthal photovoltaic platform

This paper presents the dynamic optimization of a pseudo-azimuthal tracking system for photovoltaic modules regarding the growth of energetic efficiency. The study targets on the one hand the optimization of the mechanical device of the tracking mechanism (developed with the MBS software solution ADAMS), and on the other hand the optimization of the control system model (conceived with the DFC software EASY5). The main aspect consists of using the

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A gear with translational wheel for a variable transmission ratio and applications to steering box

The paper presents the geometric and functional characteristics of a gear with ascending variable ratio, based on the gear with rack and geared segment. This gear can be used for the steering boxes of some low power vehicles (without servo-system). The steering gearbox requires an increase (around 30%) in the transmission ratio from the middle position (rectilinear displacement of the vehicle) to the extreme positions (turning/avoiding obstacles/parking).

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