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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.

This work presents a study on the related basic aspects with the accelerated tests used in the industry to determine or to confirm the reliability of an item and of the methodologies currented to analysis of the accelerated tests of life of the products. Are argued the importance of the models for each distribution and the methodologies applied in the work.It is implemented programs of computation in VISUAL BASIC language that allow the management and the adequacy for the processing of the data proceeding from the accelerated tests with constant stress and simple failure mode, for complete data, and with censorship the right or multiple, using the distribution of Weibull, Log-normal and Normal, combined with the most used models (Arrhenius model and Inverse Power Law), the program allows to the processing of the data of the accelerated tests for two methods, Squared Minimums and Maximum Likelihood Principle.

The objective of this paper is to study the design characteristics more viable to build an autonomous vehicle for disabled people (AVD). In this paper, some components are examined for available options and how these options effect the performance of the vehicle. Besides, the dynamic model of a tricycle configuration of AVD is shown. The equations of motion governing the behavior of the vehicle are obtained with the Newton and Euler's equations. Through the dynamic equations, the analyses of dynamic stability and dirigibility for the configuration are made and compared with other configurations with different kinds of driving and steering. Considering the results of stability and dirigibility, a fuzzy controller for navigation and obstacle avoidance control is design. The fuzzy controller was simulated and the results indicate that it is better use the velocity control only on final approach to goal position.

This work is basically a dirigibility study applied to tricycles of human traction, HPT - Human Powered Tricycle. The behavior of the vehicle is simulated in a track with compacted floor, contend curves, straight line, up and down grades. A simplified mathematical model is used to model the system (vehicle + cyclist). As the system of equations obtained is extremely coupled and non-linear, it is necessary to use numeric procedures to solve the equations and to obtain the behavior of the system during its path in the racetrack. The influences of the track and the mass center position of the vehicle in its stability, the behavior of the vehicle using chainset transmissions and CVTs (Continuously Variable Transmission) are also analyzed.

The main objective of this work is the analysis of the reliability of mechanical components, as well as its application in failure tests commonly used in the practice, in this case, tests for obtaining and verification of the natural frequency associated to the first vibrational mode of turbocharger blades. Of the statistical theory applied to tests of components, it was made a rising of the types of used tests and its application with respect to the sampling of the population in study. Soon after, an analysis is proceeded on correlation and regression of the obtained data of the tests and of the adjustment of curves. Experimental tests were accomplished in the bank of tests of Schwitzer in two different models of turbocharger, and mensured the natural frequencies in a certain number of samples, all of them with the same number of blades..

Autonomous guided vehicles, called AGVs, are important components of factory automation and manufacture system integration that requires both technical and management skills. In this paper, an AGV prototype equipped with IR detectors and IR range sensors is programming to follow a route line on the floor and avoid some obstacles on the way. The motion of the experimental AGV is promote by two DC motor with build-in gearbox, working with simultaneous PWM control in closed-loop operation. This AGV is designed to operate in environments such as offices and shop floor, in order to carry light loads on flat surfaces and ramps with positive and negative inclination. Simulations tests with ADAMS® are compared with some experimental results in order to validate the model and the prototype approaches.

The design methodology have been proved its effectiveness concerned to new products development, and due to the systematic approach it allows great variety of solutions and concepts developed in the early concept design phase. This paper shows two efficient methods in concepts generation, they are: the brainstorm and the morphologic chart. Both were successfully used and the result was a new concept of wheelchair motorization which the electric motors are activated only when the force applied over the propulsion ring exceeds a preset value. This new concept was registered at INPI as an invention patent.

The design methodology have been proved its effectiveness concerned to new products development, and due to the systematic approach it allows great variety of solutions and concepts developed in the early concept design phase. Axiomatic design was use to create collaborative strategies aiming to reduce the number of control strategies tests. Besides only one of required functions was developed and test each time. A wheelchair dynamic model was developed to test the strategies. At the end of the processes a role and complex control strategy was developed and only validation tests were need to apply the solution in wheelchair motorization.

This study aims to evaluate the impact that changes in the parameters of the project to a continuously variable transmission has on its ability to transmit torque and power. A half-toroidal transmission is cinematically analyzed and key geometric parameters and their relationships are studied and characterized. A change in the parameters of the transmission geometry allows a verification of their influence on the entire system live-time for any type of cycle, as defined in the theory of life provided the causes of failure, fatigue and subsurface. Additionally is possible to evaluate the capability of transmitting torque through the theory of Elasto-Hydrodynamic (EHD) contact relationship and the range of possible transmission ratio to be achieved. In this paper, a geometric model of a traction based Half-toroidal CVT (see figure 1) were explored by adding new geometric parameters related to the system control mechanism (the roller tilting angle).

One traditional solution to start an internal combustion engine is the starter motor. Since its conception little was changed in its operational dynamics, even after passing by several design optimization processes. This fact elapses from the absence of application of an analysis tool capable to express the existing relations between its subgroups and the functions that these play. 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 starter motor is divided hierarchically in subsystems according to the existing assemblies. The operation chain is then separated through static and dynamic inspections during its use in the combustion engine.

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.

One traditional solution to start an internal combustion engine is the starter motor. Little has been changed in its operational dynamics and conception, even after several design optimization processes. This fact stems from the absence of application of an analysis tool capable of showing the existing relations between its subgroups and the functions performed. But, once that these relations are explained and the basics functions are revealed, it is possible to generate a group of new technical solutions to perform the same functions. In order to achieve this goal, the present work applied a Morphological Analysis on the group of functions that is necessary and sufficient for a starter motor. The analysis of the Morphological Field revealed the nowadays trend of technical solutions and some solutions that hasn't been explored yet.

In this work the main objective is the development of systems for motorization of conventional wheelchairs, and the great mass of wheelchairs now available in Brazil of the simplest type than they don't allow the pure and simple conversion for motorization. In this aspect the problem comes as a challenge because the great variety of models and types of wheelchairs and the lack of a rigorous normalization impose the use of technologies of search of solutions and the application of methodology knowledge and systematic of project. In this way, firstly a study will be accomplished on the object wheelchair, containing: historical, origin, types and characteristics. The following step will be the search of the possibilities of motorizing conventional wheelchairs, limitations and applications.

The increasing market of the continuously changeable transmissions 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. Knowing, that the transmissions are part of the train of force of any vehicle, the model will go to include the characteristics of exit of the engine, torque and rotation and all the components of an automatic transmission that uses CVTs. The initial objective is to determine the geometry of functioning and the positioning of the leather strap in the CVT. Saber its behavior, if it is playing its role in the excellent way.

Improvement of fuel economy is one of the most important development targets of modern passenger car engines. Modern solutions such as Direct Injection, Variable Valve Trains, or Cylinder Deactivation help to obtain this requirement. Each one of these techniques optimize the thermodynamic efficiency of the engine. However, the mechanical structure of combustion engines shows many areas of possible optimization regarding the mechanical efficiency. Engine friction affects the overall fuel consumption, mainly under low speed conditions combined with part load. Low speed/part load conditions are relevant for the real life fuel consumption of an engine, as well as friction improvements have significant effects on the fuel economy. The valve train drive produces the dominant friction portion under these conditions. Hence the friction optimization of this engine subsystem is one of the key issues regarding mechanical efficiency.

Due to the current changes in the automotive industry several new technologies are being developed and the old ones analyzed. The epicyclic gear trains, or planetary gear trains, are important in the automatic transmissions. In this paper a model is presented to describe the behavior of the transmission during the process of gear change. For this the system chose must be fully described, that means the relation among the rotations of the components must established.

Epicyclic gear trains are important part of automotive transmissions. They are present in automatic transmissions and in differentials of most vehicles. The dynamic behavior of a single epicyclic gear is well known, and this study presents the results obtained based in a model of a complete transmission. Initially the Wilson gearbox is presented. The main principles of the model are described. Following, the results of a simulation using the model are shown. Finally, the influence of the inertias in the model are presented and it is done some discussion about it

In this paper a review about epicyclic gear trains (EGTs) or planetary gear trains (PGTs) is initially presented. These gear trains are transmission systems of high kinematic complexity and difficult visualization. However, their advantages are many: they are compact, light, allow high speed reductions, possess high reliability because they have constant engagement, possess bifurcating capacity and power addition, and allow multiple transmission ratio. One of their main applications is the automatic transmission or power trains of passenger cars and other modern vehicles e.g. trucks, buses, etc. Then, some classic automatic transmission boxes e.g. Simpson, GM Hydra Matic 440 PGT, Ravigneaux, etc. and the TEPiciclo software are shown. This software was created to help in design development for automatic transmission of light vehicles with two simple PGTs linked.

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.