Brake-by-Wire
VerifiedHow the rear brakes blend friction braking with the MGU-K's energy recovery, since both act on the same rear wheels at once.
On the rear axle, the MGU-K recovering energy under braking and the physical brake discs are both trying to slow the same wheels at the same time. Brake-by-wire is the electronic system that blends the two, adjusting how much of the braking force comes from energy recovery versus the discs, lap by lap and even corner by corner, so the total braking feel stays consistent to the driver.
This matters because the amount of energy available to recover changes: a nearly-full energy store can't accept much more charge, so the system has to lean more on the physical brakes at that moment and compensate so the pedal doesn't suddenly feel different.
It's a genuinely hard engineering problem, getting the blend wrong makes the rear brakes feel inconsistent under braking, which is dangerous at speed, and why brake-by-wire calibration is a real area teams compete on, not just a background detail.