Impacts of AMT Gear-Shifting on Fuel Optimal Look Ahead Control

2010-01-0370

04/12/2010

Event
SAE 2010 World Congress & Exhibition
Authors Abstract
Content
For a fuel optimal gear shift control, when look ahead information is available, the impact of the automated manual transmission (AMT) gear-shifting process is analyzed. For a standard discrete heavy truck transmission, answers are found on when to shift gears, prior to or when in an uphill slope. The gear-shifting process of a standard AMT is modeled in order to capture the fuel and time aspects of the gear shift. A numerical optimization is performed by dynamic programming, minimizing fuel consumption and time by controlling fuel injection and gear. Since a standard AMT does not have look ahead information, it sometimes gears down unnecessarily and thus gives a significantly higher fuel consumption compared to the optimal control. However, if gearing down is inevitable, the AMT gear-shifting strategy, based on engine thresholds, is well-functioning so that the optimal control only gives marginal additional savings. To attain the possible fuel reductions it is shown that the occasion of shifting gear must be chosen to ensure an adequate engine speed in order to get a sufficient engine power after the gear shift. The reduced propulsion of an AMT gear-shifting process, and the resulting vehicle retardation, must be considered.
Meta TagsDetails
DOI
https://doi.org/10.4271/2010-01-0370
Pages
11
Citation
Ivarsson, M., Åslund, J., and Nielsen, L., "Impacts of AMT Gear-Shifting on Fuel Optimal Look Ahead Control," SAE Technical Paper 2010-01-0370, 2010, https://doi.org/10.4271/2010-01-0370.
Additional Details
Publisher
Published
Apr 12, 2010
Product Code
2010-01-0370
Content Type
Technical Paper
Language
English