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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.

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 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.

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.