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The increasing interest into hybrid electric vehicles imposes the need to provide computational support for design choices during the development of these vehicles. This paper presents the use of a new methodology which allows for automatically generating topologically different hybrid powertrain concepts, and evaluating their performance. Since the energy management controller plays an important role in the performance assessment, a modular framework based on optimal control theory is used for assessing the closed-loop performance of different hybrid powertrain architectures. This paper illustrates how the concept generation methodology can be combined with optimal control in order to compare the closed-loop performance of a series and parallel hybrid powertrain.

Most modern automatic automotive transmissions are complex mechanical systems composed of multiple planetary gearsets that are connected by shafts, clutches and brakes. Creating a design that supports the desired transmission ratios while requiring a minimal amount of components is a challenging task that is commonly tackled by an engineer with experience and intuition. This paper introduces an approach for the exhaustive synthesis of automotive transmissions composed of two planetary gearsets, two clutches and two brakes that can be deployed in automotive drivetrains. By modeling the components of an automotive transmission based on their possible mechanical connections and additional user-defined specifications a constraint satisfaction problem is derived. An iterative solving process exhaustively generates all possible transmission design with the specified set of components. Further the generated designs are filtered and analyzed such that the designer is served only with unique, valid and useful transmission designs. Finally a set of generated, novel 4-speed transmission designs is presented.

The design of automatic transmissions is a challenging task due to complex power flows and high variability of architectures. To overcome those difficulties a methodology is proposed which uses computational design synthesis to generate transmission designs. The methodology is efficiently dealing with the complexity and variability of transmissions while the engineer is focusing on the application of his engineering knowledge. An analysis of 1022 patented transmissions is shown and highlights the trend of increasing complexity in order to achieve higher capability. The generation of innovative transmission designs is presente d producing designs with improved properties.