Systems, methods, and devices for control of actuators are provided. In aspects, the systems, methods, and devices provided herein enable the generation of sharp cutoff haptic effects of both limited and extended duration. The systems, methods, and devices use open loop braking signals to generate the sharp cutoff haptic effects. The braking signals are determined based on predictions of system response made according to driving signals used to cause the haptic effects in the actuators. Numerous other aspects are provided.

Provided herein is a method for calibrating a clutch by searching for the minimum of a multi-dimensional surface including determining the error between a spline function and recorded data relating to clutch characteristics, creating a multi-dimensional surface corresponding to the error values, determining the minimum of the multi-dimensional surface using the steps of performing a Steepest Gradient & Direction determination step and conducting a Golden Section Search and Switch Direction Step to find a minimum that meets a predetermined closing condition. Additionally, provided herein is a computer-implemented system for calibrating the clutch.

An electronic control unit performs lockup clutch engagement control in the sequence of fast fill control, constant-pressure standby control and command pressure raising control, and starts the lockup clutch engagement control from that one of the fast fill control and the command pressure raising control which is later in sequence than the other, as a command pressure for a control oil pressure at a transition time point for making a transition to the lockup clutch engagement control rises, in making the transition to the lockup clutch engagement control during the lockup clutch release control. Therefore, when the command pressure for the control oil pressure is equal to or higher than a predetermined value that is needed to carry out packing for narrowing a pack clearance of a lockup clutch, the lockup clutch engagement control is started from the command pressure raising control.

A friction engagement element control system is provided, which includes a friction engagement element including friction plates, which are an input-side friction plate and an output-side friction plate, and an actuation system configured to engage the input-side friction plate with the output-side friction plate with a pushing force, the friction plates having a characteristic in which a friction coefficient thereof decreases as a rotational difference between the friction plates increases. The device includes a controller configured to control the pushing force so that the negative slope characteristic becomes a positive slope characteristic in which a frictional force of the friction engagement element decreases as the rotational difference decreases, when engaging the friction engagement element.

Systems, methods, and devices for control of actuators are provided. In aspects, the systems, methods, and devices provided herein enable the generation of sharp cutoff haptic effects of both limited and extended duration. The systems, methods, and devices use open loop braking signals to generate the sharp cutoff haptic effects. The braking signals are determined based on predictions of system response made according to driving signals used to cause the haptic effects in the actuators. Numerous other aspects are provided.

An automatic transmission system of a vehicle and a corresponding adaptation method utilize an automatic transmission comprising a hydraulic friction clutch and a controller configured to continuously perform a feedforward adaptation procedure that models wear of the clutch, the feedforward adaptation procedure comprising obtaining a set of operating parameters each indicative of wear of the clutch, model the wear of the clutch based on the set of operating parameters using a clutch wear model, and determine a clutch offset for controlling application of the clutch based on the modeled clutch wear, and control application of the clutch based on the determined clutch offset.

A friction engagement element control system is provided, which includes a friction engagement element including friction plates, which are an input-side friction plate and an output-side friction plate, and an actuation system configured to engage the input-side friction plate with the output-side friction plate with a pushing force, the friction plates having a characteristic in which a friction coefficient thereof decreases as a rotational difference between the friction plates increases. The device includes a controller configured to control the pushing force so that the negative slope characteristic becomes a positive slope characteristic in which a frictional force of the friction engagement element decreases as the rotational difference decreases, when engaging the friction engagement element.

A method for determining reference values of a sensor is provided. The reference values correspond to a disengaged operating condition or to an engaged operating condition of a form-locking shift element (A, F). With the aid of the sensor, at least one operating parameter of the shift element (A, F) determinable during a disengagement and during an engagement of the shift element (A, F). A torque, an actuation force of the shift element (A, F), and a differential speed between shift-element halves of the shift element (A, F) are varied during the determination of the reference values of the sensor in such that the form-locking shift element (A, F) is transferred into the disengaged operating condition or into the engaged operating condition.

An automatic transmission system of a vehicle and a corresponding adaptation method utilize an automatic transmission comprising a hydraulic friction clutch and a controller configured to continuously perform a feedforward adaptation procedure that models wear of the clutch, the feedforward adaptation procedure comprising obtaining a set of operating parameters each indicative of wear of the clutch, model the wear of the clutch based on the set of operating parameters using a clutch wear model, and determine a clutch offset for controlling application of the clutch based on the modeled clutch wear, and control application of the clutch based on the determined clutch offset.

Controlling a multiplate clutch situated between an input shaft and an output shaft for the switchable transmission of torques, wherein in the event of a torque request and a subsequent engagement of the multiplate clutch, includes: a) determining a setpoint engagement force, acting in an axial direction, of the multiplate clutch for transmitting a setpoint torque to the output shaft; b) determining and setting a limiting engagement force that is less than the setpoint engagement force, and c) setting the setpoint engagement force in a time-delayed manner;
wherein a transmission of an actual torque is achieved by limiting the setpoint engagement force to the limiting engagement force, so that a maximum actual torque that is transmitted upon engagement of the multiplate clutch exceeds a setpoint torque to be transmitted by at most 5%.