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In the automotive area, mobile robot theory with artificial intelligence had demonstrated an incredible potential and interest of several researchers that are involved on the issue of board intelligent systems on passenger cars to perform daily jobs as, navigation without collision, control vehicle speed, parking, etc. This paper will present a path planner using a neural controller trained based on potential fields, in order to determine the trajectory and a fuzzy controller to determine the differential robot kinematics for the parallel parking maneuver task. A simulator presents the neural network training and the fuzzy logic application, from any initial point. The trajectory results can be compared with the theory and the vehicle kinematics can be verified through the simulator.

The purpose of this paper is to experimentally analyze structural-borne contributions of noise, vibration and harshness during tire rolling, also called Road NVH, in a passenger vehicle using energy transfer path analysis method (TPA), applied in a case study. During the investigation, the influences of the accelerations and forces through the A-arm front suspension bushings are highlighted due their contribution to the estimated overall interior noise, which is correlated to measured overall interior noise. The structural contribution begins as a direct result of tire vibration from surface interactions. These mechanical vibrations, mainly below 450 Hz, are transmitted to all chassis and body subsystems, resulting into noise and vibration perceived by the passengers in the cabin interior. This study is motivated by improvements in Powertrain NVH and Wind Noise, which unbalance Road NVH on various conditions.

It is presented a theoretical and experimental study about noise attenuation device in hydraulic power steering systems. Due to the noise reduction from other vehicle sources, as engine, hydraulic system noise contribution has become more relevant. The hydraulic power steering system major noise source is the pump, contributing with its own operating noise, and also by pressure pulsation in pipeline, which in turns excite another sources. The operating principle of attenuation system is the destructive superposition of pressure waves, and for the phenomenon occurrence, the waves must be 180° out of phase. Delay between the waves is obtained through system parameter settings, geometric and physic. So it was performed system modeling, focusing in the pipeline in order to characterize the system components, and also the model validation was done through comparison between model and test data obtained with commercial system.

The clutch actuation system is directly linked to vehicle easy of operation and ergonomics. For passenger cars, a comfortable pedal force is considered light when it is under 100 N and hard if over 130 N. For Commercial vehicles, about 170 N are considered acceptable. This work looks forward to obtain a pedal curve in Excel which simulates the real one and can low down actuation systems developing time. For in such way, it points to cares about master cylinder actuation geometry, stroke and pedal effort variations in the way that it is comfortable for the driver, works on low hydraulic pressure and is able to keep functionality during whole clutch plate and disc life. Some calculations about lever and master cylinder push rod dimensions are realized in the way of keeping actuation angles drawing limits. Empirical evaluations about losses in components (hydraulic and mechanical) for determination of stroke of pedal and pedal effort actuation are also done.

Before the changes occurred in the production spectrum, communication needs to become more efficient. Hard competition in global market leads to decrease of the cycle time of product design. To improve research inside the industry, the use of management tools to robust design must be complemented with efficient communication's systems between Supply Chain and Product Design Process. This necessity can be proved studying the application of the management tools (QFD - Quality Function Deployment) to Product Development in a Formula SAE team. Its results, in a qualitative view, indicate the economic viability and the cost deployment to minimize the design stage and points up these multifunctional research teams structure and this professional graduate as a way to satisfy the communication failures. Diante das mudanças ocorridas no cenário produtivo, a comunicação necessita se tornar muito eficiente.

This paper presents the results of an experimental modal analysis performed on a prototype chassis of an off-road competition vehicle. The vehicle was designed by the Mini Baja EESC-USP team for the annual competition promoted by SAE Brasil. The goal of this experimental modal analysis is to validate a finite element model of the chassis, in order to develop a flexible multibody dynamic model of the complete vehicle. A preliminary finite element modal analysis of the test article was carried out in a free-free boundary condition. A random signal was used for FRFs acquisition. A multimode identification algorithm was used to acquire the system's modal parameters. Based on this information a swept sine was employed for mode shapes identification.

This paper describes the methodology adopted at T-Systems do Brasil, for performing handling analysis of commercial vehicles. Its application to an intercity bus with 3 axles is presented. The objective is to improve primary suspension characteristics alone, with respect to both comfort and handling and to study the behavior of the full vehicle with respect to handling and to improve it through the changes of primary suspensions characteristics. The methodology adopted was the development of a complete multibody model of the bus (Figure 4) in ADAMS, considering all the major non-linearities of the actual vehicle, such as air spring and shock absorber curves, suspension bump stops and tire model (Delft). Once having the model, several analyses were carried out including, modal, single lane change, double lane change, steering impulse and sine steering sweep.

The present work carries out static and kinematical studies of front suspensions of a Brazilian medium sized passenger car. The concept of virtual prototyping with the use of multibody system modelling techniques is employed by ADAMS, a package developed by Mechanical Dynamics Inc.. The concept of virtual prototyping allows vehicle development without the need of physical prototype construction. ADAMS uses the description of the geometric suspension, inertia parameters from its parts and how the parts are connected to generate a full model of the system. The type of analysis which can carry out include vertical and steering behaviour (in the case of a front suspension). These analysis are generated in graphical as well as an animation. The results include among others: toe-in angle, camber and caster angle, ride rate, and so forth. The use of the virtual prototyping concept, has made easier the modelling and analysis of this type of mechanism.

The present paper presents an overview of Multibody Systems (MBS) modelling techniques with respect primarily to its historical developments, to the mathematical formalisms which have been used to model such systems and the computer implementations of such formalisms. A specific aim of this paper is also to present in a simplified way, Kane's Method, a formalism largely employed in MBS programs in the market today. The paper also discusses the advantages and disadvantages of each approach in relation to the problems they are better suited to cater for.