Development and Testing of an Automatic Transmission Shift Schedule Algorithm for Vehicle Simulation

SAE 2015 World Congress & Exhibition
Authors Abstract
The Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) tool was created by EPA to estimate greenhouse gas (GHG) emissions from light-duty (LD) vehicles [1]. ALPHA is a physics-based, forward-looking, full vehicle computer simulation capable of analyzing various vehicle types combined with different powertrain technologies. The software tool is a MATLAB/Simulink based desktop application. In order to model the behavior of current and future vehicles, an algorithm was developed to dynamically generate transmission shift logic from a set of user-defined parameters, a cost function (e.g., engine fuel consumption) and vehicle performance during simulation.
This paper presents ALPHA's shift logic algorithm and compares its predicted shift points to actual shift points from a mid-size light-duty vehicle and to the shift points predicted using a static table-based shift logic as calibrated to the same vehicle during benchmark testing. An explanation of, and a process for tuning, the user defined parameters is presented and example applications of the algorithm in transmission and engine sensitivity studies are described.
Meta TagsDetails
Newman, K., Kargul, J., and Barba, D., "Development and Testing of an Automatic Transmission Shift Schedule Algorithm for Vehicle Simulation," Engines 8(3):1417-1427, 2015,
Additional Details
Apr 14, 2015
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Journal Article