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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.

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.

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 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.

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.

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 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.

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 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 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.

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..