A system and method for controlling a transmission gear shift in a vehicle having a driveline and an electric motor operable to output torque to the driveline includes applying a negative motor torque to the driveline to reduce driveline oscillations resulting from the transmission gear shift. The negative motor torque is based on vehicle conditions occurring after the transmission gear shift has begun and before the transmission gear shift is complete.

A construction machine includes: an engine driving at least one hydraulic pump configured to supply operating oil to a hydraulic actuator; an exhaust adjustment mechanism adjusting a flow rate of exhaust from the engine; and a control device controlling the exhaust adjustment mechanism. The control device determines whether or not a first downhill traveling condition and/or a second downhill traveling condition are/is satisfied. When at least one of the first downhill traveling condition and the second downhill traveling condition is satisfied, the control device controls the exhaust adjustment mechanism such that the exhaust adjustment mechanism executes exhaust brake.

Methods and systems are provided for operating a driveline of a hybrid vehicle that includes an internal combustion engine, a rear drive unit electric machine, an integrated starter/generator, and a transmission are described. In one example, inertia torque compensation is provided to counter inertia torque during a power-on upshift.

A control method of a variable speed electric motor system, which includes an electric device and a planetary gear transmission device, the control method includes: a step of accepting an instruction for a number of rotations of an output shaft; a step of calculating a number of rotations of a variable speed electric motor based on the number of rotations of the output shaft; a step of determining whether the calculated number of rotations of the variable speed electric motor is in an uncontrollable range; and a step of performing uncontrollable speed range operation for repeatedly and alternately performing a forward direction minimum rotation number instruction for driving the variable speed electric motor at a minimum number of rotations in a forward direction, and a reverse direction minimum rotation number instruction for driving the variable speed electric motor at a minimum number of rotations in a reverse direction.

A method for detecting parasitic power circulation within a work vehicle may include controlling an operation of the work vehicle such that a transmission of the work vehicle has a first output speed and determining a first power value associated with power transmitted through a drive shaft of the work vehicle at the first output speed. The method may also include adjusting the operation of the work vehicle such that the transmission has a second output speed that differs from the first output speed and determining a second power value associated with power transmitted through the drive shaft at the second output speed. In addition, the method may include comparing the first and second power values to a predetermined relationship to determine whether the work vehicle is currently experiencing parasitic power circulation, wherein the predetermined relationship is associated with operation of the work vehicle without parasitic power circulation.

A control apparatus: controls air fuel ratios so that while combustion is performed sequentially through a plurality of cylinders, at least one cylinder where rich combustion is performed and the other cylinders where lean combustion is performed are generated; makes an internal combustion engine execute a catalyst warming operation for promoting warm-up of a three-way catalyst; and controls a second motor generator so that a torque difference between output torque from a rich cylinder where the rich combustion is performed and output torque from a lean cylinder where the lean combustion is performed is eliminated on an output shaft during the catalyst warming operation.

A method for operating a drive train of a motor vehicle includes closing a frictional-locking shift element that serves as a starting element of a transmission in a slipping manner such that slip at the frictional-locking shift element is reduced by a defined pressure control of the frictional-locking shift element, determining a differential rotational speed at the frictional-locking shift element or a variable dependent on the differential rotational speed while the frictional-locking shift element is closing, and, when the differential rotational speed or the variable dependent on the differential rotational speed is less than a first limit value or reaches the first limit value, changing a rotational speed of the drive unit in such a manner that the differential rotational speed or the variable dependent on the differential rotational speed becomes less than a second limit value or reaches the second limit value within a defined time period.

A vehicle powertrain includes an engine and a transmission, each controlled by controllers that communicate with one another. When the vehicle is coasting in certain gears, a one-way clutch over-runs. When the driver depresses the accelerator pedal (tips in), the transmission controller adjusts a transmission torque demand limit which is communicated to the engine controller. In response, the engine controller adjusts the engine torque, resulting in a smooth re-engagement of the one-way clutch.

A method for operating a multispeed transmission in a motor vehicle, provided with planetary gearings which can be switched with four switching elements to different gear ratios, and which can be connected by input elements and output elements to a driven input shaft and to an output shaft. The reaction elements can be coupled or locked with a brake, wherein the four planetary gearings can be switched by two brakes and by three shifting clutches to eight forward gear ratios. In the higher gear ratios, at least one first shifting clutch is connected to produce a force flow in the transmission, and in the lower gear ratios, at least a second shifting clutch is connected to produce a force flow in the transmission.

A method for operating a drive device for a motor vehicle, which has an internal combustion engine, an electric motor, and a gearshift transmission. A drive shaft of the internal combustion engine can be coupled by a shift clutch to a motor shaft of the electric motor and the motor shaft is coupled to a transmission input shaft of the gearshift transmission. A driven shaft of the drive device is coupled to or can be coupled to a transmission output shaft of the gearshift transmission. In a first shifting state, the shift clutch is disengaged for decoupling of the internal combustion engine and the electric motor and, in a second shifting state, is engaged for coupling of the internal combustion engine and the electric motor.