A new approach to cope with the disadvantages of the self energizing drum brake by means of mechatronics is described. The introduced system allows for control of the brake factor of a duplex drum brake from C*=2 to C*=6. Variations of the friction factor μ due to fading will be compensated to a certain extent using an electronically controlled mechanism adjusting the support base of the leading shoes of the brake. The required application forces are up to seven times lower compared to a disk brake at equal braking torques. Theory, design and measurements of a prototype brake with mechatronically controlled self energizing are the topics of this paper. The described research work was carried out at the Department of Automotive Engineering (fzd) of the University of Darmstadt.