Research: In the previous phase “Requirements – Target Definition and Concept Study”, several concept design options were reduced to two distinct topologies. For both topologies, the optimum gear numbers and gear ratios were identified in order to meet the vehicle performance and efficiency targets. Their performance and efficiency were evaluated in different drive cycles. Furthermore, the most promising topology was implemented in a hybrid F-max tractor analytical model. The energy saving through hybridization with an e-axle was calculated in the reference cycles (1).
Results: The hybrid truck proposed by Ford Otosan will include an e-axle as the key component of electrified powertrain. The e-axle is a powerpack that consists of electric motor(s), a multi-speed gearbox and a differential. Project partners Ford Otosan and FEV will design and implement an e-axle to the baseline truck, in order to reach the project targets of at least 10% energy saving and zero emission drive.
The activities planned in this phase of the project have been successfully executed. Several concept design options are reduced to two distinct topologies. For both topologies, the optimum gear numbers and gear ratios are identified in order to meet the vehicle performance targets. Their performance and efficiency are evaluated in different duty cycles. Furthermore, the most promising topology is implemented in a hybrid F-max tractor analytical model. The energy saving through hybridization with an e-axle is calculated in the reference cycles.
According to the results of the concept phase, the hybrid F-max tractor with the proposed e-axle concept can satisfy the project targets.
Research: In the “Layout Design” phase, the most promising topology was further detailed. Successfully completed activities in this layout design phase include: e-Motor selection, evaluation of vehicle level requirements with traction curve analyses, development of a duty cycle from Ford Otosan target drive cycles, 3D layout modeling; gear design, modeling of system deformations; safety analyses of transmission components such as gears, bearings, shafts and splines; housing concept design, lubrication system development, shifting system development, and initial supplier selection for sensors. According to the results of the layout design phase, the selected concept can be implemented in an e-axle system that will satisfy the project targets.
Outputs: Outputs are the detailed 3D model with all the construction parameters and the necessary analysis results which will ensure a proper function of the demonstration vehicle. In addition to the gear train, the lubrication and cooling systems have been analyzed, and the results are documented.
Outlook: All work conducted so far will be elaborated and deepened with additional activities such as the finite element analysis of the housing, multibody simulations of the shifting system and additional detail design work such as generation of the drawings and tolerance stack up analyses being performed. The process will be documented in the following phase.
Figure 2: E-axle exhibition at Aachen Colloquium 2022