Patent ID: 7706949
Filing Date: 2010-04-27
Classification: B60K,B60L,B60W,F16H,Y02T,Y10S,Y10T

Abstract:
1. Method for executing a shift between a first fixed gear and a second fixed gear in a powertrain system including an engine connected to an electro-mechanical transmission selectively operative in one of a fixed gear and a continuously variable mode, comprising: monitoring input speed of an input shaft connecting the engine to the electro-mechanical transmission; monitoring output speed of an output shaft of the electro-mechanical transmission; fixing a total elapsed time to execute the shift; deactivating an off going clutch and operating in the continuously variable mode; determining an initial speed of an oncoming clutch; calculating a time-based speed profile for the oncoming clutch; controlling the input speed of the input shaft based upon the time-based speed profile for the oncoming clutch and the output speed of the output shaft; determining the speed of the oncoming clutch in accordance with the input speed of the input shaft; and determining a change in the speed of the oncoming clutch during a fixed total elapsed time and controlling the input speed of the input shaft during the operating in the continuously variable mode; wherein the time-based speed profile for the oncoming clutch is determined in terms of the output speed of the output shaft over the fixed total elapsed time, comprising a first time step comprising a ramp up in speed of the oncoming clutch, a second time step comprising a steady state change in speed of the oncoming clutch, and a third time step comprising a ramp down in speed of the oncoming clutch as synchronization of the oncoming clutch occurs.