Clutch contact points

A method for controlling a twin clutch transmission including at least two partial drive trains, each of which is coupleable to a combustion engine using a respective clutch (K1, K2), comprising the following steps to be carried out on the inactive partial drive train:

• shifting from an engaged gear to a neutral gear (100) with the clutch of the inactive partial drive train open;
• determining the drag torque MS of the input shaft of the inactive partial drive train during a predetermined period P1 (130);
• closing the clutch of the inactive partial drive train up to a predetermined position in which a clutch torque is transmitted and determining a total torque M of the input shaft of the inactive partial drive train during a predetermined period P2 (140);
• determining the clutch torque MK of the input shaft of the inactive partial drive train from the drag torque MS and the total torque M as the sum of the drag torque MS and the clutch torque MK;
• and
• determining a contact point position from the absolute value of the determined clutch torque MK and a clutch characteristic of the clutch of the inactive partial drive train, wherein the periods P1 and P2 are selected in a way that their sum is shorter than the period in which the neutral gear is engaged.

A method for controlling a twin clutch transmission including at least two partial drive trains, each of which is coupleable to a combustion engine using a respective clutch (K1, K2), comprising the following steps to be carried out on the inactive partial drive train:

• shifting from an engaged gear to neutral with the clutch of the inactive partial drive train open;
• determining the drag torque MS of the input shaft of the inactive partial drive train during a predetermined period P1 (130);
• closing the clutch of the inactive partial drive train up to a predetermined position in which a clutch torque is transmitted and determining a total torque M of the input shaft of the inactive partial drive train during a predetermined period P2 (140);
• determining the clutch torque MK of the input shaft of the inactive partial drive train from the drag torque MS and the total torque M as the sum of the drag torque MS and the clutch torque MK;
• and
• determining a contact point position from the absolute value of the determined clutch torque MK and a clutch characteristic of the clutch of the inactive partial drive train, wherein the clutch of the inactive partial drive train is subsequently opened and a gear is engaged in the inactive partial drive train, the gear being the same as or different from the gear from which a shift to neutral occurred with the clutch open.