Technique for operating a vehicle brake having a hydraulic service brake and an electric parking brake

A method for operating a vehicle brake, wherein the vehicle brake comprises:

• a hydraulic service brake having an actuating piston, which for generating a first braking force component, is movable, under the action of a hydraulic pressure, into an actuating position in which the actuating piston presses a friction lining against a rotatingly supported brake disc, and
• an electric parking brake that is designed to build up a second braking force component that acts on the brake disc, in that an actuating element of the parking brake is supported on the actuating piston in order to press the friction lining against the brake disc, wherein the method comprises the following steps:
• ascertaining the hydraulic pressure;
• determining a first braking force component based on the ascertained hydraulic pressure;
• establishing a second braking force component to be set by means of the parking brake, based on the first braking force component and a desired total braking force;
• ascertaining a rigidity of the vehicle brake by detecting an actuating travel covered during the actuation of the parking brake as a function of a detected actuating force;
• and
• establishing a position of the actuating element of the parking brake to be set based on the second braking force component and the rigidity of the vehicle brake.