Have you ever noticed how dirty the front wheels of vehicles are? Do you know why? Brake dust!

The wear of brake pads and disks is a ubiquitous source of secondary emissions in all urban centers around the world!

Reducing secondary emissions in the automotive sector is a critical step towards a sustainable future, as it helps to protect public health and the environment. Brake pollution is the leading source of secondary emissions, and it contributes to particulate emissions that are harmful to human health causing respiratory problems and increase the risk of heart disease. Therefore, it is essential to implement innovative solutions to reduce brake pollution and particulate emissions. This need is expressed by the newest regulation proposals, such as the Euro 7, that will consider brake emissions as part of automotive targets.

One technology that reduces brake pollution in electric vehicles is regenerative braking. This feature reduces brake wear and tear by minimizing the need for conventional braking, leading to a significant reduction in particulate emissions. The regenerative braking solution is, however, limited, since it is not able to completely eliminate braking action (in emergency conditions, or when the batteries are at full SOC).

Through solutions such as regenerative braking, or even low-emission brake pads, and advanced driving assistance systems can reduce the impact of secondary emissions on public health and the environment, but not completely solve the problem. Thus, a "real" zero-emissions solution must be proposed to tackle the problem, and our team found it: Its name is ZEDS!

The Zero-Emission Driving System combines in-wheel electric motors with an innovative braking system, composed by a rotor, a stator with a coil and a gap between the fulfilled with a magneto-rheological fluid. This fluid is a yield fluid capable of changing its yield stress characteristic in function of the magnetic field applied on it. By suitably generating a magnetic field, ZEDS is able to change the physical characteristics of the MR fluid and generate sufficient braking torque even in emergency conditions. In particular, applying a current to the coil, it is possible to generate a Magnetic Field on the fluid, generating a yield stress change capable of decelerating the rotor system.

ZEDS does not rely on pad-disk friction, so no wear is generated, completely eliminating all sources of secondary emissions. Apart from the environmental goal, the integration between an electrically actuated brake and an electric motor grants ZEDS other advantages such as a faster response time, easily controllable system for active stability actuation, and a maintenance-free braking solution. ZEDS features a braking system, with all parts and materials recyclable and fit to automotive applications, coupled with an in-wheel motor, a type of electric motor that is already commercially available and fitted in several electric vehicles. In addition, the aforementioned restrictions introduced in the Euro 7 standard are driving the automotive market increasingly towards zero-emission brake system solutions, making ZEDS a strong candidate for the braking systems of tomorrow!