Flatter tires will produce greater rolling resistance.

CarBuzz recently discovered a new patent filed by Daimler, owner of Mercedes-Benz.

It is a user-operated backup brake device with a valve to reduce tire pressure. In the case of emergency braking, if the braking system fails, the tires will flatten to help the car slow down.

The system consists of a central control unit and an air pressure reduction unit connected to the tires of the vehicle. These two systems are activated when the central braking unit fails or malfunctions.

The patent description mentions that this braking system is designed for pure electric vehicles and hybrid vehicles, but it can also be used in traditional internal combustion engine vehicles.

The main reason for its existence is to switch to the new braking system. Since electric vehicles use regenerative braking, they essentially have two braking systems. The main method is to regain energy by effectively braking the motor. Once the battery is fully charged, the car will switch back to the traditional friction-based system.

Due to the complexity involved, modern cars use brake-by-wire technology. However, the user interface remains the same. The driver stepped on the pedal and the car brakes. But now there is an intermediate system that needs to decide how to use the braking force. The driver steps on the pedal, and the wire control system records the pressure and decides which method to use to slow the car.

If the wire control system fails, the result can be catastrophic. Ford recently encountered problems with six Mach-E models in Norway. The regenerative braking system continuously recovers energy, causing the battery to overheat.

In order to solve this problem, Daimler proposed a new backup system. It only works when the main unit of the actuator fails or even a simple error occurs. In this case, the brake pedal is connected to the backup unit, which is a basic friction system. The main new feature is the air release valve, which can reduce tire pressure.

Why are you in your car? Well, its simplicity is beautiful. This is the opposite of increasing the tire pressure to the maximum allowable limit to reduce friction and fuel consumption.

Flat tires have a larger contact area with the road surface, which increases rolling resistance. However, this is a balancing act. If the tire pressure is reduced too much, the tire will easily fall off the rim. It can also affect the handling characteristics of the vehicle.

Daimler thought of this, which is why the system is connected to all four wheels. Ideally, it will lower the tire pressure of all four tires, but it will start with at least one tire and then work from there. After the tire pressure is reduced, the maximum speed of the car will be limited, and there will be a warning system to let the driver know.

The system can also be used to restore the pressure to the original level, although this particular aspect is not mentioned in the main claim section. Combined with a tire pressure monitoring system, vehicles equipped with such a system can adjust tire pressure.

This is not the first time Daimler has used an on-board inflation system. Mercedes-AMG G63 6x6 is equipped with an on-board compressor that can be used to deflate and inflate tires. This is a large and cumbersome system mounted above the two rear axles.

As you can see from the sketch, the new system is much smaller. Mercedes-Benz will launch a series of electric vehicles in the United States, starting with the Mercedes-Benz EQS.