Traditional Hydraulic Brakes Could Soon Be A Thing Of The Past

 As cars, trucks, and SUVs become increasingly electrified, their hardware will also slowly head towards a more digital era. Braking systems, up until recently, have all mostly relied on an antiquated, yet highly redundant technique of using hydraulics to squeeze a caliper onto a rotating disc called the rotor. But when electric vehicles (EVs) came to be, their ability to slow the car down using the electric motor's change of direction, through regenerative braking, gave us a new look at how modern vehicles can come to a stop.

Automotive parts suppliers Brembo and ZF's latest developments in braking technology don't rely on regenerative braking to revolutionize the way brakes operate. But their brake-by-wire technology takes inspiration from EVs, and could soon signal the end of the traditional hydraulic braking system.

A New, "Dry" Type Of Brake-By-Wire System

Brake-by-wire technology isn't new. Introduced about a decade ago, the idea behind it is to reduce the amount of mechanical components required to complete a car's full braking system. Essentially, what these first systems did was send a signal from your brake pedal to an electronic master cylinder, which then still relied on the system's hydraulic pressure to move the caliper around.

But, what both Brembo and ZF are working on moves the needle a tad further. Brembo will be the first to put its Sensify system onto the market as early as this year, while ZF's Electro-Mechanical Braking (EMB) system is scheduled for 2028.

What these "dry" systems effectively do is delete the entire brake booster and brake lines, essentially getting rid of the entire hydraulic system in the process. ZF's approach is very much like that of a racing simulator. The brake pedal sends a signal to a small electric motor installed within the brake caliper itself, telling it to squeeze the caliper according to pedal force. But this system suggests only using electric motors on the rear brakes. The front brakes would still rely on the traditional hydraulic system, for reliability reasons, ZF says. From Diego Cusi, ZF's director of engineering:

A pedal simulator observes driver intent though pedal travel and force and translates it into a signal that is processed through a central computer. That signal is now going to be issued out to the four corners.

What's also interesting about this system is that the current feeling of the anti-lock brake system (ABS) kicking in will disappear. This is caused by the fact that the brake-by-wire system is never actually connected to the brake pedal itself. Some will say that such a system will completely delete the brake pedal feel, and these people would be right. But carmakers have already surprised us in the realm of electronic power steering systems. So I'm not too worried.

Brembo Wants To Favor A Fully Electric System

Brembo's system, however, is much more advanced, and could be of great use in the EV space. While ZF suggests a "hybrid" brake-by-wire system, Brembo would prefer moving forward with electric motors on all four wheels. However, only an EV could supply an electrical system powerful enough to sustain such a system. Hence why ZF believes its integration of both electronics and hydraulics would work better with gasoline-powered vehicles equipped with 48-volt mild hybrid systems.

In both cases, however, these technologies elevate braking systems to a whole new level, with many benefits, such as cost-reduction and reduced weight from the absence of brake lines and boosters. While the caliper itself is heavier due to the integrated electric motors, brake-by-wire remains overall lighter and less expensive to manufacture, to say nothing of the reduced maintenance costs down the line.

That's because these systems don’t require brake fluid flushes. Brake pads will also last longer, and fuel economy is expected to improve, since electronic brake calipers do without the traditional drag effect caused by conventional systems. Neither Brembo nor ZF have said in which vehicles their systems will be integrated first, but my guess is that high-end, luxury vehicles will be first on the list.