摘要 |
A vehicle includes an engine and transmission. A first rotating clutch engages as an oncoming clutch during a predetermined shift maneuver having a total required clutch energy. A second rotating clutch acts as a holding clutch. A third rotating clutch engages as an additional oncoming clutch during the shift maneuver to share clutch energy with the first rotating clutch. The third rotating clutch, when not engaged, has a zero slip speed relative to the input member. A method includes building a shift table for a transmission design, including identifying slip speed ratios, with respect to the input member, for each clutch, and selecting, from the shift table, a direct drive or other gear state in which three of the rotating clutches are simultaneously operating at a zero slip speed ratio with respect to the input member. The third rotating clutch engages during the shift maneuver.
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