A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

A control system for a transmission reverser having an output gear, a forward disconnect device, a first reverse disconnect device, and a second reverse disconnect device includes one or more controllers with processing and memory architecture configured to execute control logic to control the transmission reverser in a forward mode and a reverse mode. In the forward mode, the one or more controllers command the first reverse disconnect device to disengage and the forward disconnect device to engage to rotate the output gear in a forward direction. In the reverse mode, the one or more controllers command the first reverse disconnect device to engage and the second reverse disconnect device to engage to rotate the output gear in a reverse direction.

A motor vehicle has at least two drive motors, at least one drive motor being an electric machine; a high-voltage accumulator; and an automatic gearbox, having at least one fixed transmission ratio and at least one power-split transmission ratio for transmission regulation starting from the at least one fixed transmission ratio. The motor vehicle further includes an electronic control unit, which is designed such that, when a gear change command is present, the shifting element to be opened of the fixed transmission ratio to be disengaged is unloaded in a torque-controlled manner by at least two of the drive motors. For the shifting element to be opened, the torque load is calculated and observed. The torque load is observed with the objective of bringing about a load change by way of a zero crossing in order to produce a no-load state at the shifting element. For producing the no-load state of the shifting element to be opened, a first drive motor and a second drive motor are controlled in a power split manner such that they, in terms of rotational speeds, maintain the transmission of the previously engaged fixed transmission ratio, and, in terms of torque, put the shifting element to be opened in an at least nearly no-load state, and a load change is brought about at the shifting element to be opened by a differential rotational speed, opposite the calculated torque load at the shifting element to be opened, being specified at the shifting element.

A control system for a power transmission unit configured to shift an operating mode smoothly by manipulating engagement devices, and to simplify a structure of the power transmission unit. The control system is configured to reduce a speed difference between an axially stationary engagement element and a reciprocatable engagement element of a second engagement device when shifting from a first continuously variable mode to a second continuously variable mode by engaging the second engagement device. After the second engagement device has been engaged completely, a first engagement device is disengaged.

An object is to reduce a delay in response. An automatic gear changing control device includes a sleeve which is moved by an actuator to perform an engagement operation, an engine which is connected to an input shaft, and a control unit which controls the movement of the sleeve by the actuator and controls the rotation of the input shaft by the engine or a motor generator. The control unit performs synchronization control of controlling the rotation of the input shaft for the engagement operation at a different gear stage after the engagement is released and starts shift control of moving the sleeve to an engagement completion position by the actuator before at least the synchronization is completed.

A control system for a power transmission unit configured to shift an operating mode smoothly by manipulating engagement devices, and to simplify a structure of the power transmission unit. The control system is configured to reduce a speed difference between an axially stationary engagement element and a reciprocatable engagement element of a second engagement device when shifting from a first continuously variable mode to a second continuously variable mode by engaging the second engagement device. After the second engagement device has been engaged completely, a first engagement device is disengaged.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

A method for operating a vehicle drive train (1) comprising a prime mover (2), transmission (3), and comprising a driven end (4) may include limiting, during a demand for engaging a form-locking shift element (A, F) of the transmission (3) when a rotational speed of the driven end (4) is close to zero, a rate of change of a transmission input torque present at the form-locking shift element (A, F) to a value. Below the value, forces present at the form-locking shift element (A, F) during an engagement process are less than a load limit. Above the value, irreversible damage to the form-locking shift element (A, F) occurs.

A form-locking shift element may include a first shift-element half and a second shift-element half which are engageable with each other by moving at least the first shift-element half. A method for determining an operating condition of the form-locking shift element may include monitoring a position of the first shift-element half with a sensor, and, when a value of a signal generated by the sensor is greater than an applicable value and when the first shift-element half is actuated and displaced towards an engaged operating condition, determining that the shift element is sufficiently engaged to transmit a torque at the form-locking shift element. The applicable value corresponds to a defined overlap between the first and second shift-element halves that is less than an overlap when the first shift-element half is in the engaged operating condition.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.