Electronic brake boost on secondary brake system

A braking system for a vehicle, comprising:

• a primary brake system including a brake pedal;
• a secondary brake system;
• a plurality of braking units including a first braking unit, a second braking unit, a third braking unit, and a fourth braking unit controlled by the primary brake system when the primary brake system is active, at least one of the plurality of braking units controlled by the secondary brake system when the primary brake system is inactive;
• a primary controller controlling fluid pressure in the primary brake system;
• a secondary controller controlling fluid pressure in the secondary brake system independently of the primary controller;
• an actuator being part of the primary brake system, the actuator controlled by the primary controller;
• a reservoir in fluid communication with both the primary brake system and the secondary brake system;
• and
• a boost pressure which is generated by the secondary brake system when the primary brake system is inactive;
• wherein the primary controller actuates the actuator to control the fluid pressure in the primary brake system to selectively actuate the first, second, third, and fourth braking units when the primary brake system is active and the secondary brake system is inactive, and when the primary brake system is inactive, the secondary brake system is active and the secondary controller is configured to generates the boost pressure in the third braking unit and the fourth braking unit to generate braking force and the driver of the vehicle applies force to the brake pedal to generate braking pressure in the first braking unit and the second braking unit.

A braking system for a vehicle, comprising:

• a primary brake system including a brake pedal;
• a secondary brake system;
• a plurality of braking units including a first braking unit, a second braking unit, a third braking unit, and a fourth braking unit controlled by the primary brake system when the primary brake system is active, at least one of the plurality of braking units controlled by the secondary brake system when the primary brake system is inactive;
• a primary controller controlling fluid pressure in the primary brake system;
• a secondary controller controlling fluid pressure in the secondary brake system independently of the primary controller;
• an actuator being part of the primary brake system, the actuator controlled by the primary controller;
• a reservoir in fluid communication with both the primary brake system and the secondary brake system;
• and
• a boost pressure which is generated by the secondary brake system when the primary brake system is inactive;
• a first mode of operation, and during the first mode of operation, the primary brake system is active such the first braking unit, the second braking unit, the third braking unit, and the fourth braking unit are all controlled by the primary controller and the driver of the vehicle applies force to the brake pedal to generate braking pressure such that the plurality of braking units are actuated, decelerating the vehicle, while the secondary brake system is inactive;
• and
• a second mode of operation, and during the second mode of operation, the secondary brake system is active such that the secondary controller controls the third braking unit and the fourth braking unit, and the primary brake system is inactive;
• wherein the primary controller selectively actuates the actuator to control the fluid pressure in the primary brake system to selectively actuate the plurality of braking units when the primary brake system is active, and when the primary brake system is inactive, the secondary brake system generates the boost pressure in the at least one of the plurality of braking units controlled by the secondary brake system;
• wherein during the second mode of operation, the driver of the vehicle applies force to the brake pedal to generate braking pressure such that the first braking unit and the second braking unit are actuated to generate braking force, and the secondary controller configures the secondary brake system to generate the boost pressure to actuate the third braking unit and the fourth braking unit to generate braking force, and the braking force of the first braking unit and the second braking unit is combined with the braking force generated by the third braking unit and the fourth braking unit to decelerate the vehicle.