Powertrain for a vehicle and method for controlling a powertrain in a vehicle

A powertrain for a vehicle including a driving shaft configured to rotate with a first rotational speed while exerting a driving torque, said powertrain configured to transmit mechanical energy from the driving shaft to wheels of the vehicle, wherein a controllable clutch is configured to controllably couple an output shaft with the driving shaft, the powertrain further including a control system comprising a controller to control said rotational speed and said driving torque with a drive control signal, said driving torque having a desired driving torque sign, and to control the clutch with a clutch control signal specifying a desired extent of engagement to be provided by the clutch between the driving shaft and the output shaft, the control system comprising a clutch slip indicator to provide a signal indicative for an extent of slip between the driving shaft and the output shaft, wherein the controller has a safety operational mode wherein it controls an engagement of the controllable clutch with a feedback loop in which said desired extent of engagement as specified by the clutch control signal is positively correlated to a difference between said extent of slip as indicated by the slip indicator and a positive reference value for said extent of slip, wherein the slip indicator indicates the extent of slip with a sign that is the product of the sign of the difference between the rotational speed of the driving shaft and a rotational speed of the output shaft and the desired driving torque sign.