A vehicle braking system (20) has a primary braking unit (22) with a first pressure generating unit (34) and a first reservoir (26). The vehicle braking system (20) further has a secondary braking unit (24) with a second pressure generating unit (52) and second reservoir (70). A method of operating the vehicle braking system (20) includes actuating the pressure generating unit (34) of the primary braking unit (22) thereby pressurizing a fluid at a wheel cylinder (30) to slow or stop the vehicle. The wheel cylinder (30) is depressurized in response to an electrical signal provided to an electronic control unit (100,102). The fluid is transferred from the wheel cylinder (30) to the second reservoir (70). The fluid path (PI) between the wheel cylinder (30) and the second reservoir (70) is shorter and has less fluid resistance than the fluid path (P2) between the wheel cylinder (30) and the first reservoir (26). The present invention further comprises two braking systems. The present inventions are intended for fast pressure depressurization at quick start or launch control.

The present disclosure relates to an electronic brake system including a reservoir in which the pressurized medium is stored, a hydraulic pressure supply device provided to generate a hydraulic pressure by moving a hydraulic piston forward or backward and having a first pressure chamber provided on a front side of the hydraulic piston and a second pressure chamber provided on a rear side of the hydraulic piston, a hydraulic control unit provided to control a flow of the hydraulic pressure to be transmitted from the hydraulic pressure supply device to a wheel cylinder, a longitudinal acceleration sensor provided to detect a longitudinal acceleration of a vehicle, and a controller provided to control the hydraulic pressure supply device and the hydraulic control unit, wherein the controller determines the hydraulic pressure generated by the hydraulic pressure supply device based on the longitudinal acceleration of the vehicle, determines a braking mode based on the determined hydraulic pressure, and performs the determined braking mode.

Method and apparatus are disclosed for traction control based on friction coefficient estimation. An example vehicle includes a plurality of sensors to measure qualities of a surface of a road and an anti-lock brake system module. The anti-lock brake system module (a) estimates confidence values for different road surface types based on the qualities of the surface of the road, (b) estimates a coefficient of friction between the road and tires of the vehicle based on the confidence values, and (c) adapt a traction control system by altering a target slip based on the coefficient of friction.

Provided is an electronic brake system including: a hydraulic pressure supply device including a motor, and configured to generate a hydraulic pressure by rotating the motor to move a piston in a first direction or a second direction; a hydraulic circuit configured to guide the hydraulic pressure generated by the hydraulic pressure supply device to a wheel cylinder; a motor position sensor configured to detect a rotation of the motor; a pressure sensor configured to detect a hydraulic pressure of the hydraulic circuit; and a controller configured to identify a position of the piston based on the rotation of the motor, and if the detected hydraulic pressure is greater than or equal to a reference pressure, identify whether a target pressure is securable based on the position of the piston, and control a direction change of the piston based on whether the predetermined target pressure is securable.

The vehicle control device: controls the drive device and the braking device such that an actual acceleration representing an actual acceleration of the vehicle coincides with a target acceleration for driving the vehicle so that the vehicle stops at a preset target stop position; acquires the target acceleration every time a predetermined time elapses, and sets the target acceleration to a value such that the magnitude of the change amount does not exceed the threshold change amount when the magnitude of the change amount representing the difference between the target acceleration and the previous target acceleration exceeds the threshold change amount; and sets the threshold change amount to a larger value than when the emergency condition is not satisfied in a case where a predetermined emergency condition is satisfied in a case where a driving force or a braking force larger than in a normal state is required.

A system for controlling launch of a vehicle includes a pressure-providing device constructed and arranged to deliver a pressure medium to wheel brakes of the vehicle. A pressure chamber is fluidly connected with the pressure-providing device and is configured for containing the pressure medium. An electronic control unit has a processor circuit that is constructed and arranged, during a launch mode of the vehicle, to control the pressure-providing device to cause fluid from the wheel brakes to be directed to the pressure chamber so as to release the pressure medium from the wheel brakes, permitting launch of the vehicle.

A vehicle includes wheels, brakes, and a controller. The wheels are configured to propel the vehicle. The brakes are configured to generate a braking torque at the wheels. The controller is programed to, in response to (i) a commanded braking torque and (ii) a relative jounce between two of the wheels exceeding a threshold, operate the brakes to increase the braking torque to less than the commanded braking torque. The controller is further programed to, in response to (i) the commanded braking torque and (ii) a droop of at least one of the wheels exceeding a threshold, operate the brakes to increase the braking torque to less than the commanded braking torque.

In a method for activating and deactivating a control unit which can be used to control an electrically activatable assembly, the control unit is switched between a waking state, a sleep state and a deactivated state, wherein in the sleep state, the control device is disabled but can be transferred into the waking state by means of a sensor signal.

A differential locking axle control system that can cause the axle to automatically lock and unlock at any vehicle speed, up to a predetermined maximum speed, or any wheel spin rate up to a predetermined maximum, when a vehicle is being steered either in a straight line or around a curve while taking traction and global positioning factors into account.

A vehicle reverse traveling speed limiting apparatus includes a fluid pressure detector, a brake driver, a limiting speed setter, and a reverse traveling speed controller. The fluid pressure detector detects a brake fluid pressure. The brake driver causes a main brake to perform braking based on a set instruction fluid pressure. The limiting speed setter sets a limiting speed upon reverse traveling. The reverse traveling speed controller executes torque and brake controls to allow an actual vehicle speed of a vehicle to be maintained at the limiting speed. When the actual vehicle speed is higher than the limiting speed, the reverse traveling speed controller sets the instruction fluid pressure to allow the actual vehicle speed to be converged to the limiting speed, and executes, even when the brake fluid pressure is higher than the instruction fluid pressure, the brake control to allow the instruction fluid pressure to be maintained.