A method of operating a motor vehicle transmission includes measuring an operating temperature of the transmission, the transmission having at least seven torque transmitting mechanisms and at least three planetary gear sets, each planetary gear set having three gear members; determining if the transmission is in a park mode; determining if the operating temperature is below a predetermined threshold; if the operating temperature is below the predetermined threshold and the transmission is the park mode, implementing a shift delay mitigation process that includes engaging a fourth torque transmitting mechanism and a firth torque transmitting mechanism of the at least seven torque transmitting mechanisms so that they are locked to a ground to prevent a first gear member of the first planetary gear set from moving, which, in turn, prevents an input torque being transferred to a park pawl.

A method for the dynamically expanding play correction according to a method for hysteresis compensation for an actuator and for a shift fork which is movable by this actuator via an electric motor having a rotor and a stator and which guides a gearshift sleeve, by means of a cellular automaton, wherein a torque ripple of the actuator and a mechanical displacement of the gearshift sleeve are compensated independently of one another or in combination by means of a learning algorithm.

A method for the dynamically expanding play correction according to a method for hysteresis compensation for an actuator and for a shift fork which is movable by this actuator via an electric motor having a rotor and a stator and which guides a gearshift sleeve, by means of a cellular automaton, wherein a torque ripple of the actuator and a mechanical displacement of the gearshift sleeve are compensated independently of one another or in combination by means of a learning algorithm.

A shift control device of a vehicle including an internal combustion engine and a multi-speed transmission in series, the shift control device comprises: a control portion providing a downshift control in which an input shaft rotation speed of the multi-speed transmission is increased through a torque-up of the internal combustion engine toward a post-shift input shaft rotation speed in a neutral state where a release-side engagement device to be released during a downshift of the multi-speed transmission is released, so as to engage an engagement-side engagement device to be engaged after the shift. In the case of a shift pattern having a large internal inertia of the multi-speed transmission, the control portion controls a torque capacity of the engagement-side engagement device to a value greater than zero before starting a torque-up control of the internal combustion engine.

A shift control device of a vehicle including an internal combustion engine and a multi-speed transmission in series, the shift control device comprises: a control portion providing a downshift control in which an input shaft rotation speed of the multi-speed transmission is increased through a torque-up of the internal combustion engine toward a post-shift input shaft rotation speed in a neutral state where a release-side engagement device to be released during a downshift of the multi-speed transmission is released, so as to engage an engagement-side engagement device to be engaged after the shift. In the case of a shift pattern having a large internal inertia of the multi-speed transmission, the control portion controls a torque capacity of the engagement-side engagement device to a value greater than zero before starting a torque-up control of the internal combustion engine.

An electronic control unit suppresses gear shifting more significantly in a second travel mode than in a first travel mode. Accordingly, frequent gear shifting of an automatic transmission in the second travel mode is suppressed, and superior ride quality is obtained. Meanwhile, an amount of a hysteresis in a gear shifting map is smaller in the second travel mode than in the first travel mode. Thus, duration of travel at an optimum gear stage is extended in the second travel mode, and fuel economy is improved. That is, in the second travel mode, drive power responsiveness to an acceleration and deceleration operation as in the first travel mode is unnecessary. Thus, even when gear shifting is suppressed, there is a low possibility that a driver feels a sense of discomfort.

A system and method for minimizing shift cycling for low speed engine operation with a vehicle cruise control. A vehicle control system operating in a cruise control mode determines a deficiency in vehicle speed between a measured vehicle speed and a cruise set speed. The deficiency is determined by comparing the vehicle speed to the cruise set speed, and includes using the compared value to find a cruise speed margin, which is continuously updated. While the cruise control system is active, the control system logic determines the time at which a transmission upshift occurs based on the cruise speed margin. The vehicle speed, at which the upshift is made, is determined as a function of the updated cruise speed margin. An upshift is not made, if a likely drop in vehicle speed would result in the event a downshift would occur once the upshift is made.

A system for controlling fluid pressure to a transmission system through a MEMS microvalve includes a transmission controller configured to receive a target command pressure, a current system command pressure input signal, and a transmission system operating temperature. A power determination module determines a temperature-related power factor from the target command pressure, the current system command pressure input signal, the transmission system operating temperature received in the controller, and a look-up table within the controller. A power signal module adjusts the current system command pressure input signal by the temperature-related power factor and applies the adjusted current system command pressure input signal to the MEMS microvalve via the controller.

A system for controlling fluid pressure to a transmission system through a MEMS microvalve includes a transmission controller configured to receive a target command pressure, a current system command pressure input signal, and a transmission system operating temperature. A power determination module determines a temperature-related power factor from the target command pressure, the current system command pressure input signal, the transmission system operating temperature received in the controller, and a look-up table within the controller. A power signal module adjusts the current system command pressure input signal by the temperature-related power factor and applies the adjusted current system command pressure input signal to the MEMS microvalve via the controller.

A control apparatus for an automatic transmission includes an ECU. The ECU stores a N1 speed downshift/a N2 speed downshift/a N1 speed upshift/and a hysteresis lines. The hysteresis line is a predetermined distance above the N1 speed upshift line, and is below the N2 speed downshift line. The ECU controls the speed of the automatic transmission based on a quantity of state of a vehicle, and the plurality of stored shift lines, and execute, when an N speed is established, a first downshift that changes a speed from the N speed to an N2 speed, when the quantity of state of the vehicle is in a region above the hysteresis line, after the quantity of state of the vehicle has risen above the N1 speed downshift line.