ZF unveiled a novel electro-mechanical brake system during the Next Generation Mobility Day in Shanghai.
The system employs electric motors at each wheel to produce braking force, eliminating the need for a hydraulic system and brake fluid. This brake system, designed for the international market, was developed across ZF’s research facilities in China, the USA, and Germany.
Dr Holger Klein, CEO of ZF Group, highlighted the significance of their new electrically controlled braking system as a critical addition to their networked chassis systems portfolio. He emphasized that such by-wire systems mark the beginning of a new era in vehicle control, particularly beneficial for software-defined and electric vehicles, enhancing design and development flexibility.
The ‘dry’ brake system operates without brake fluid. Brake pressure is generated by electric motors, with brake signals transmitted electrically from the pedal to the motor, hence the term ‘dry brake-by-wire’.
This system boasts several advantages over traditional braking systems. It offers shorter braking distances, improved energy recovery, and reduced maintenance costs. During automatic emergency stops, the system can reduce braking distance by up to nine meters at 100 km/h. Electric vehicles can also benefit from up to 17% more range due to better energy recuperation.
‘Dry brake-by-wire’ systems significantly reduce residual drag torques, common in conventional systems, minimizing particulate emissions from brake wear and enhancing energy efficiency and range in electric vehicles.
Eliminating the hydraulic system reduces assembly and logistics costs in vehicle production, involving fewer components. Over the vehicle’s lifespan, the absence of brake fluid changes means less maintenance.
Despite lacking a mechanical link between the brake pedal and actuators, the braking experience remains akin to hydraulic brakes. The safety of data transmission and energy supply to the motors is assured through system and connection duplications, similar to aviation by-wire systems.
ZF’s extensive portfolio also includes electronically controlled steering, brakes, and damping systems for software-defined vehicles. Klein noted that interconnected chassis systems improve driving dynamics. These systems enhance vehicle control, braking efficiency, steering flexibility, high-speed stability, and overall range and efficiency.