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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 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.

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.

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).

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.

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.

Chassis dynamometers are important equipment to perform vehicular experiments in the automotive industry. Usually, these equipments are used according to standard procedures for emissions, fuel consumption, and performance analyses. In this paper, an alternative procedure was developed to experimentally determine the dynamometer inertia and losses related to bearings and transmission systems. Furthermore, a study on the tires rolling resistance, considering a double tire-roller contact, was carried out. The experiments were performed in a 4x2 chassis dynamometer with four rollers, equipped with an eddy current brake (coupled to a transmission reducer of 2.5 instrumented with a 3000 Nm torque flange) and with a 30 CV AC electric motor (coupled to a planetary transmission with reduction of 4.43 and instrumented with a 500 Nm torque flange). The dynamometer was also instrumented with an encoder system for speed measurement.

A Torque converter is a type of hydro-mechanical device, vastly utilized in the automatic transmission of vehicles and other machines. It is a critical component of the transmission system, having a direct impact on the fuel economy and vehicle´s performance. Computational Fluid Dynamics (CFD) has been employed by many authors and engineers to better understand the complex behavior of fluids inside of torque converters, in a way that it provides design improvements and increases model accuracy. This article presents a methodology that applies CFD as a tool in the design process of automobile torque converters. Therefore, this paper performs an extensive review of CFD associated with torque converters, and the principal concepts are stated and used to have a better understanding of the system’s dynamic behavior. Additionally, this article details some of the work done to develop an automotive torque converter model using the commercial software ANSYS CFX.

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.

It is considerable the number of research around the subject of motorization of conventional manual wheechairs, however the found models don't take care of the real necessities of the wheelchair users. In the manufacture the necessity of an independent vehicle for the load transport exists. With the increasing necessity in Brazil to develop the knowledge in the area of independent vehicles and not being still available a towboat of tests adjusted to approach such problems. The articulated towboat is an intelligent independent vehicle to tow loads. The users of conventional manual wheelchairs will go to use this vehicle when to need motorization, that is in ascent cases, descending of ramps, or long distances. This vehicle possesss practical applications that they can assist systems of support to the rehabilitation of physical and motor deficiencies and also systems automatized of manufacture.

The search for better energy efficiency is leading the developments in automotive industry, looking for opportunities to reduce losses, optimizing the design and getting better efficiency of every component. This paper will present a non-linear dynamic study of interaction between commercial vehicle and the environment, considering all the influence of their dynamic characteristics in the fuel consumption. The first step is to analyze all variables that influence the dynamic behavior and then construct a mathematical model based on energy and based on forces (Newton). The interaction between the vehicle and its environment and the response of it will be considered as influent aspects and should be included into vehicle dynamic modeling.

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.