A system and method for operating the same includes a drive sprocket assembly, a clutch lever, a user interface generating a reverse signal at a user interface, a wheel speed sensor generating a wheel speed signal, a transmission position sensor generating a transmission position signal and a vehicle control module receiving the reverse signal, the wheel speed signal and the transmission position signal. The vehicle control module engages a reverse gear at a drive sprocket in response to the reverse signal, the wheel speed and transmission gear position and controls the drive sprocket assembly in response to the clutch lever.

A system and method for operating the same includes a drive sprocket assembly, a clutch lever, a user interface generating a reverse signal at a user interface, a wheel speed sensor generating a wheel speed signal, a transmission position sensor generating a transmission position signal and a vehicle control module receiving the reverse signal, the wheel speed signal and the transmission position signal. The vehicle control module engages a reverse gear at a drive sprocket in response to the reverse signal, the wheel speed and transmission gear position and controls the drive sprocket assembly in response to the clutch lever.

A drive axle of an electric vehicle has first and a second drive wheels (R1, R2) with wheel axles (a1, a2), a first electric machine (EM1) and a second electric machine (EM2) with a common rotation axis (m), a transmission (G3) with a transmission input shaft (EW) and a transmission output shaft (AW), and an axle differential (DI) with a differential input (DIK) and two differential output shafts (3a, 3b). The first electric machine (EM1) is connected to the transmission input shaft (EW) and the transmission output shaft (AW) is connected to the differential input (DIK). The second electric machine (EM2) can be connected as an additional drive when necessary.

Methods and systems for a clutch assembly in an electric drive axle of a vehicle are provided. In one example, a clutch assembly in a gear train is provided that includes a locking clutch. The locking clutch includes a gear including a plurality of teeth having at least one tooth with a tapered end, an indexing shaft rotationally connected to an output shaft, a shift collar mounted on the indexing shaft, configured to translate on the indexing shaft into an engaged and disengaged configuration, and including a plurality of teeth on a face, where at least one tooth in the plurality of teeth in the shift collar includes a tapered end, and an indexing mechanism coupled to the shift collar and the indexing shaft and configured to accommodate for indexing between the indexing shaft and the shift collar during shift collar engagement.

Methods and systems for a clutch assembly in an electric drive axle of a vehicle are provided. In one example, a clutch assembly in a gear train is provided that includes a locking clutch. The locking clutch includes a gear including a plurality of teeth having at least one tooth with a tapered end, an indexing shaft rotationally connected to an output shaft, a shift collar mounted on the indexing shaft, configured to translate on the indexing shaft into an engaged and disengaged configuration, and including a plurality of teeth on a face, where at least one tooth in the plurality of teeth in the shift collar includes a tapered end, and an indexing mechanism coupled to the shift collar and the indexing shaft and configured to accommodate for indexing between the indexing shaft and the shift collar during shift collar engagement.

A vehicle control device controls a vehicle provided with a transmission having a direct gear and normal gears including an overdrive gear having a lower gear ratio than the direct gear. The device includes a travel segment determination unit which determines a forward travel segment having a different road slope from a current travel segment, a current gear position selection unit that selects a current gear position based on a travel resistance of the vehicle, a forward gear position selection unit that selects a forward gear position based on a travel resistance in the forward travel segment, and a shift control unit that selects whether or not to upshift the transmission based on a situation until the vehicle reaches the forward travel segment, when an upshift to the overdrive gear is newly selected in a case where the current gear position and the forward gear position are the direct gear.

A vehicle control device controls a vehicle provided with a transmission having a direct gear and normal gears including an overdrive gear having a lower gear ratio than the direct gear. The device includes a travel segment determination unit which determines a forward travel segment having a different road slope from a current travel segment, a current gear position selection unit that selects a current gear position based on a travel resistance of the vehicle, a forward gear position selection unit that selects a forward gear position based on a travel resistance in the forward travel segment, and a shift control unit that selects whether or not to upshift the transmission based on a situation until the vehicle reaches the forward travel segment, when an upshift to the overdrive gear is newly selected in a case where the current gear position and the forward gear position are the direct gear.

A method for operating a power shiftable transmission of a motor vehicle, the transmission including a control unit, an input shaft, an output shaft, a gear set, and multiple shift elements, the method including transmitting, with the control unit, a request for a reduction of a drive torque acting on the input shaft for carrying out an upshift, and determining, with the control unit, whether the reduction is completely possible, partially possible, or impossible based on a signal. When the reduction is completely possible, the method includes controlling, with the control unit, a torque transmission rate of a shift element of the multiple shift elements to be engaged during the upshift according to a first way. When the reduction is partially possible or impossible, the method includes controlling, with the control unit, the torque transmission rate according to a second way, the second way differing from the first way.

A method and system for controlling clutch friction elements of an automatic transmission is provided. The method includes retrieving information about shift clutches from a data storage unit and acquiring information required to predict a temperature of a friction element for each shift clutch, deriving a predicted temperature value of a friction element for each shift clutch by using the information about the shift clutches and the information required to predict the temperature of the friction element, predicting whether or not overheating occurs for each shift clutch by comparing the derived predicted temperature value of the friction element for each shift clutch with an allowable temperature set for each shift clutch, and determining a target shift stage while avoiding the overheating clutch with a predicted temperature value exceeding the allowable temperature, through switching to an avoidance shift mode.

The transmission control unit includes a gear ratio abnormality determination unit and a limp home control unit. The gear ratio abnormality determination unit is configured to determine that a gear ratio is abnormal when, during travelling at a predetermined gear position, a difference between an actual gear ratio, which is calculated based on a transmission input shaft rotation speed and a transmission output shaft rotation speed, and a set gear ratio at the predetermined gear position is equal to or greater than a set value. The limp home control unit is configured to, when the gear ratio abnormality determination unit determines that the gear ratio is abnormal, output a disengagement instruction for disengaging all of the plurality of friction elements, when it is confirmed that a neutral state is shifted to according to the output of the disengagement instruction, determine engagement/disengagement of a specific friction element among the plurality of friction elements based on rotation/stop information of a rotation member of the stepped transmission mechanism, and determine an evacuation gear position based on determination information on the engagement/disengagement of the specific friction element, and shift the gear position to the determined evacuation gear position.