Automatic transmission control system with direct electronic swap-shift control

A control method for controlling a multiple-ratio automatic transmission for an automotive vehicle including two gearsets controlled by pressure-actuated friction elements for providing multiple torque flow paths between an engine and vehicle traction wheels, each gearset having a controller, the method comprising the steps of:

• measuring the input speed of one gearset and the input and output speeds of the other gearset;
• monitoring shift progression and shift progression rate of the other gearset and the shift progression of the one gearset during a swap-shift;
• transferring to the controller for the one gearset the shift progression and shift progression rate of the other gearset;
• computing the desired input speed for the one gearset using the shift progression and shift progression rate from the other gearset during a swap-shift;
• measuring actual input speed for the one gearset and controlling input speed error between the desired input speed and the actual input speed in a closed-loop fashion;
• computing friction element command pressure for the one gearset;
• converting pressure data from the controller for the one gearset to torque data for the one gearset using friction element gain data for the one gearset;
• converting torque data from the one gearset to torque data for the other gearset;
• converting torque data from the other gearset to an interactive pressure value for the other gearset using friction element gain data for the other gearset;
• controlling friction element pressure for the friction element of the other gearset in a closed-loop fashion during a swap-shift using input and output speed information for the other gearset;
• and
• transferring information regarding the interactive pressure value to the one gearset for modifying the friction element pressure for the friction element of the one gearset, whereby compensation for dynamic interaction is effected for the gearsets during swap-shifts.

A control method for controlling a multiple-ratio automatic transmission for an automotive vehicle including two gearsets controlled by pressure-actuated friction elements for providing multiple torque flow paths between an engine and vehicle traction wheels, each gearset having a controller, the method comprising the steps of:

• measuring the input speed of the one gearset and the input and output speeds of the other gearset;
• monitoring shift progression and shift progression rate of the other gearset and the shift progression of the one gearset during a swap-shift;
• transferring to the controller for one gearset the shift progression and shift progression rate of the other gearset;
• computing the desired input speed for the one gearset using the shift progression and shift progression rate from the other gearset during a swap-shift;
• measuring actual input speed and controlling input speed error between the desired input speed and the actual input speed in a closed-loop fashion;
• computing friction element command pressure for the one gearset;
• computing friction element command pressure for the other gearset;
• converting pressure data from the controller for the one gearset to torque data for the one gearset using friction element gain data for the one gearset;
• converting torque data from the one gearset to torque data for the other gearset;
• converting torque data from the other gearset to a first interactive pressure value for the other gearset using friction element gain data for the other gearset;
• converting pressure data from the controller for the other gearset to torque data for the other gearset using friction element gain data for the other gearset;
• converting torque data from the other gearset to torque data for the one gearset;
• converting torque data from the one gearset to a second interactive pressure value for the one gearset using friction element gain data for the one gearset;
• controlling friction element pressure for the friction element of the other gearset in a closed-loop fashion during a swap-shift using input and output speed information for the other gearset;
• controlling friction element pressure for the friction element of the one gearset in a closed-loop fashion during a swap-shift using input speed information and output shaft speed information for the one gearset;
• transferring information regarding the second interactive pressure value to the other gearset for modifying the friction element pressure for the friction element pressure of the other gearset;
• and
• transferring information regarding the first interactive pressure value to the one gearset for modifying the friction element pressure for the friction element pressure of the one gearset;
• the controllers for the one gearset and the other gearset compensating for dynamic interaction of the gearsets during an inertia phase of a swap-shift.

A multiple-ratio automatic transmission for an automotive vehicle having an engine, a torque converter with an impeller connected to the engine and a turbine, the transmission comprising:

• a first planetary gearset with at least two ratios having a pressure-actuated brake element for effecting one gear ratio for the first planetary gearset and a pressure-actuated clutch element for effecting another gear ratio for the first planetary gearset;
• a second planetary gearset having at least three ratios having a first pressure-actuated element for effecting one gear ratio for the second planetary gearset, a second pressure-actuated element for effecting a second gear ratio for the second planetary gearset and a third pressure-actuated element for effecting a third gear ratio for the second planetary gearset;
• the first and second planetary gearsets providing multiple torque flow paths between the engine and vehicle traction wheels;
• a torque input shaft for the second planetary gearset being connected to a torque output shaft of the first planetary gearset;
• a torque output shaft for the second planetary gearset being drivably connected to the traction wheels;
• a first speed-based controller for controlling pressure at the pressure-actuated friction elements of the first planetary gearset;
• a second speed-based controller for controlling pressure at the pressure-actuated friction elements of the second planetary gearset;
• a first speed sensor for monitoring the speed of the turbine;
• a second speed sensor for monitoring the speed of the torque output shaft of the first planetary gearset;
• and
• a third speed sensor for monitoring the speed of the torque output shaft of the second planetary gearset;
• one planetary gearset being upshifted as the other planetary gearset is being downshifted, thereby effecting a swap-shift for the overall transmission ratio;
• the first and second controllers having dynamic torque-based interaction based upon monitored speed sensor information, whereby a pressure change at one of the friction elements for one of the first and second planetary gearsets will command a pressure change at one of the friction elements for the other of the first and second planetary gearsets during a time progression of the swap-shift, which results in improved quality of the swap-shift in the overall transmission ratio.

An automatic transmission for an automotive vehicle comprising:

• a simple planetary gearset and a compound planetary gearset arranged in series to establish multiple torque flow paths between an engine and vehicle traction wheels;
• a first pressure-actuated reaction brake for anchoring a sun gear of the simple planetary gearset to establish an upshift of the simple planetary gearset on an overall transmission ratio downshift;
• a second pressure-actuated reaction brake for anchoring a sun gear of the compound planetary gearset to establish an upshift of the compound planetary gearset on the overall transmission ratio downshift;
• a ring gear of the simple planetary gearset being drivably connected to a torque input element of the compound planetary gearset;
• a first controller for controlling pressure at the pressure-actuated reaction brake for the simple planetary gearset;
• and
• a second controller for controlling pressure at the pressure-actuated reaction brake for the compound planetary gearset;
• the first and second controllers having dynamic interaction whereby a pressure change at one of the pressure-actuated reaction brakes will command a pressure change at the other pressure-actuated reaction brake during a swap-shift, which results in improved quality of the swap-shift in the overall transmission ratio.

An automatic transmission for an automotive vehicle comprising a simple planetary gearset and a compound planetary gearset arranged in series to establish multiple torque flow paths between an engine and vehicle traction wheels;

• a pressure-actuated reaction brake for anchoring a sun gear of the simple planetary gearset to establish an upshift of the simple planetary gearset in an overall transmission ratio downshift;
• a pressure-actuated clutch for drivably connecting two elements of the compound planetary gearset to establish a downshift of the compound planetary gearset on the overall transmission ratio downshift;
• a ring gear of the simple planetary gearset being drivably connected to a torque input element of the compound planetary gearset;
• a first controller for controlling pressure at the pressure-actuated reaction brake for the simple planetary gearset;
• and
• a second controller for controlling pressure at the pressure-actuated clutch for the compound planetary gearset;
• the first and second controllers having dynamic interaction whereby a pressure change at the pressure-actuated reaction brake will command a pressure change at the pressure-actuated clutch during a swap-upshift which results in an improved quality of the swap-shift in the overall transmission ratio.