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The automated guided vehicles (AVGs) are normally used for the transport of materials, making great part in the manufacturing systems. This work aims at the study of the contact between ground and wheel in the AVG, thus applying the vehicle dynamics relative. For this, models of the contact between road and wheel had been made of AVG, in each model presents his considerations, simplifications and parameters as the cornering stiffness, the normal force and the sideslip. The models of the contact between road and wheel had been implemented in a multibodies program 2D and observed. The results of this work will be used in the construction of independent vehicles, because many AVGs don't take in consideration the dynamic behavior, they have a super dimension of engine so more weight and consumption of energy than they really need.

The automotive industry's recent push towards developing electric and hybrid electric vehicles is a direct response to the growing global pressure due to environmental concerns and has resulted in a search for significantly cleaner and more efficient vehicles. Not only, in order to achieve its purpose, has this search highly depended on the development of advanced technologies. Among all systems and subsystem from a vehicle the powertrain system is going to be the focus of this work. The main goal of the present work is to get a complete mapping of all the functions, components and flows of information and energy, through the application of an existing methodology of analysis, known for “function structure technique”, on the described product. Therefore, this mapping will supply a better understanding of the product architecture. First of all, the composed system, for the hybrid vehicle powertrain, is divided hierarchically in subsystems according to the existing assemblies.

This paper focus on the analysis of energy management for hybrid electric vehicles. The development of higher efficiency vehicles depends on the analysis of vehicle characteristics and driving conditions. Sizing the energy capacity of the storage system and defining the type of components, batteries or other kinds of electric components has a direct influence over the performance, consumption and autonomy of the vehicle. The forces involved in a vehicle movement such as aerodynamic drag, rolling resistance, grading resistance, are fully dependent on the conditions of the route; most situations should be represented on the driving pattern cycle, used for emissions and consumption tests, which will be presented and discussed. Modeling vehicle dynamic to analyze power and energy requirements of the vehicle during different test cycles provides an indication of the influence of hybrid technology in performance and fuel consumption.

The need for improved fuel economy for road vehicles has increased the interest in hybrid electric vehicle (HEV) and recovering vehicle energy. This paper aims to evaluate the amount of kinetic energy that could be restored through regenerative braking in a HEV. This work will not resort the Brazilian urban driving cycle NBR 6601, for this cycle does not fully represent a pattern of traffic faced regularly in urban areas, which is typically composed of heavy traffic and long periods of idleness. Therefore, a new drive cycle will be developed that better represents the Brazilian traffic. Also, considering the shortage of energy resources, the large amount of energy dissipated as heat during braking a vehicle is a recurring concern. Therefore, measuring the maximum available energy that could be restored through regenerative braking is the first step towards estimating the profit of using this technology and how it would pay off the investment in the long run.

The development of hybrid vehicles has reached in recent years a high technical and commercial importance. In general, varied vehicular settings enable a motorization with several alternatives and conventional energies combined in order to increase the performance while reducing consumption and environmental impact. In the context of hybridization, particular attention has been given to vehicles that consider a secondary driving source of electric nature, mainly in countries where its cost is relatively low when compared with the cost of fossil fuels such as gasoline. This paper aims to achieve an economic and energy analysis of a hybridized vehicle. The last one has a conventional traction front-wheel driven by an internal combustion engine (ICE) and an electric traction rear-wheel propelled by electric motors (EMs) in-wheel.

The purpose of this paper is evaluating the amount of kinetic energy available to be regenerated by a hybrid electric vehicle (HEV) undergoing the Brazilian standardized driving cycle. Improvements on energy efficiency of the cars has become an urgent target of the Brazilian industry since Brazil launched a new automotive regulation imposing the reduction of 15.5% on the fuel consumption of the vehicles to be sold in this country in 2017 comparing to 2011. The HEVs are a possible solution for this situation. They are widely known by the high efficiency, mainly the ones capable to make the regenerative breaking, rescuing an already paid energy. Before the launch of HEVs in Brazil, the feasibility of these vehicles has to be accurately studied and one aspect to be evaluated is how much energy is possible to be rescued in the Brazilian standardized driving cycle.

The aim of this article is to compare three strategies for motorization control of a servo assisted wheelchair. A servo assisted wheelchair is new conception of a therapeutic wheelchair. The model used in this development is based on doubled bicycle model which driven force applied over the rear wheels and the steering over the front wheels. For this article three strategies were developed and simulated one “on-off” control, one rule control and a fuzzy control. The most appropriated strategy for the studied system was a rule control, because it has a best performance in terms of the system displacement.

The aim of this article is to study the dynamic behavior of a system composed by a child and a wheelchair during the propulsion with a servo-assisted motorization controlled with a logic fuzzy algorithm. The model correspond a vehicle with propulsion on the rear wheels, steering is on the front wheels. The wheels were modeled as rigid and a double bicycle model was used. The fuzzy controller will act over the system applying additional forces during the wheelchair propulsion looking for increase the user mobility and will be tested and evaluated bearing on mind the increasing of the system performance.

Had to the development of new projects of vehicles more economic as for example, the hybrid vehicles, have become bigger investments in transmission systems mechanics more adjusted. Thus being the increasing market of the continuously changeable transmissions it demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. To leave of this modeling one became alterations of some components and verified the behavior of this CVT in a simulation of passage of a vehicle. This passage was drawn so that the vehicle more faced daily situations of a vehicle considered in a track accented, that requested of the transmission the reactions boundary lines that supplied to torque and power of enough engine, or, so that the vehicle executed the passage, a not to leave of the limitations of the system and the CVT.

This paper studies the stability of a system and also its dynamical behavior during propulsion. The model was based on Newton-Euler-Jourdan equations. The resulting stability equation is general and establishes the velocity limit of the vehicle. This was modeled with propulsion on the back wheels and the steering on the front wheels. To establish the forces acting over the four wheels was used single-track model twice. It was determined equations for the transversal and longitudinal accelerations and for the rotation over the yaw axes of the vehicle. The contribution of this article is general equations for stability and dynamical behavior.

Hybrid Electric Vehicles (HEVs) currently represent an alternative to reducing fossil fuel consumption used by internal combustion engines. This paper analyses, in a platform of computational simulation and also in experimental condition, the vehicle fuel consumption, before and after hybridization. It checks the similarity of behaviors and/or the investigation of possible differences between the developed mathematical model and experiments performed. Computer simulations help, through mathematical models, a better understanding of physical phenomena related to engineering problems. A well elaborated computer model has a high fidelity degree with the real systems, becoming a powerful analysis tool. The experiments besides allowing a proof of results, they contribute to a refinement of the simulated models. The hybrid technology under study is characterized by the coupling of two electric motors directly to the rear vehicle wheels.

The hybrid electric vehicle (HEVs) is an alternative to reduce the high dependence on petroleum products, because maintains the characteristics attributed to conventional vehicles such as performance, safety and trustworthiness and reduced the fuel consumption. Some modifications are necessary in the vehicle longitudinal dynamics equationing, to provide a specific power management control system, because of the electrical power source addition that complements the conventional engine and powertrain system. In this paper is used the HEV parallel configuration, where both drive systems are directly connected to the vehicle wheels, maintaining the engine/powertrain in the front wheels and electric motors directly coupled to the rear vehicle wheels.