Abstract: An actuator system includes a piezoelectric pump; an accumulator including a cylinder, a piston located in the cylinder, a port located at a first side of the piston and hydraulically connected to the pump outlet and a switching circuit, a relief port hydraulically connected to the reservoir and located at a second side of the piston, and a spring biasing the piston toward the port; and a hydraulically actuated servo including a front port hydraulically connected to the switching circuit, a back port hydraulically connected to the reservoir, and the servo causing the friction element alternately to engage and to disengage in response to a magnitude of hydraulic pressure in the servo.

Abstract: An actuator system includes a piezoelectric pump; an accumulator including a cylinder, a piston located in the cylinder, a port located at a first side of the piston and hydraulically connected to the pump outlet and a switching circuit, a relief port hydraulically connected to the reservoir and located at a second side of the piston, and a spring biasing the piston toward the port; and a hydraulically actuated servo including a front port hydraulically connected to the switching circuit, a back port hydraulically connected to the reservoir, and the servo causing the friction element alternately to engage and to disengage in response to a magnitude of hydraulic pressure in the servo.

Abstract: An engine valve control system for controlling engine valve lift during an automatic transmission shift. A plurality of engine valve actuation systems are each coupled to an individual engine valve for electronically controlling valve lift. Each valve actuation system includes a hydraulically operated piston coupled to each of the engine valves, and an electronically actuated supply valve responsive to a supply signal and coupled between the hydraulically operated piston and a source of hydraulic fluid, and an electronically actuated drain valve responsive to a drain signal and coupled between the piston and source of hydraulic fluid. A controller responsive to a shift command from a transmission controller, provides the supply and drain signals in appropriate timing and phase relationship to reduce valve lift during the automatic transmission shift.

Abstract: A system and method for controlling the ignition timing of a spark ignition internal combustion engine in a driveline that includes a multiple speed ratio transmission, at least one of whose operating speed ratios depends on the engaged or disengaged state of a clutch, the rotating inertia of the engine, equivalent vehicle inertia, a spring associated with the stiffness of the axle, inherent structural damping, and a spark advance controller-filter, whose output advances and retards the spark timing of the engine in accordance with the magnitude of engine speed and transmission output speed according to a control algorithm, which improves speed ratio control during shifts and minimizes the underdamped oscillations that result after the clutch is fully engaged.