Abstract: A method for coupling a first partial drive train of a hybrid vehicle having a first shaft, an internal combustion engine and a first electric machine, which can be selectively operated in generator or motor mode, to a second partial drive train of the hybrid vehicle having a second shaft and an electric drive machine. In a control or regulating step, a speed adjustment of the first shaft is carried out by acting on the speed of the first electric machine, wherein, at the same time, the torque of the internal combustion engine is changed in the same direction in order to achieve the same performance level of the first shaft before the speed adjustment. A computer program product and a hybrid vehicle drive train with a control device containing the computer program product, which is designed to bring about the method is provided.

Abstract: A method determines the travel of a clutch in a hydraulic clutch-actuation system. A hydraulic signal which extends between a transmitting end and a receiving end is acted upon by an acoustic signal for the generation of a wave packet. The acoustic signal on the transmitting end of the clutch-actuation system is fed into the hydraulic fluid, a wave packet generated by the acoustic signal on the receiving end is reflected back to the transmitting end, a running time of the transmitted and reflected wave packet on the transmitting end is evaluated to determine the coupling travel.

Abstract: A method determines the travel of a clutch in a hydraulic clutch-actuation system. A hydraulic signal which extends between a transmitting end and a receiving end is acted upon by an acoustic signal for the generation of a wave packet. The acoustic signal on the transmitting end of the clutch-actuation system is fed into the hydraulic fluid, a wave packet generated by the acoustic signal on the receiving end is reflected back to the transmitting end, a running time of the transmitted and reflected wave packet on the transmitting end is evaluated to determine the coupling travel.