Brake control device for vehicle

TLDR: In this paper, the authors proposed a method to prevent rapid reduction of brake liquid pressure through antiskid control by calculating a slip ratio based on a second estimated car body speed reduced at a given deceleration from a given value.

Abstract: PURPOSE:To prevent rapid reduction of a brake liquid pressure through antiskid control by calculating a slip ratio based on a second estimated car body speed reduced at a given deceleration from a given value when a first estimated car body speed is reduced to a very low car body lower than a given value. CONSTITUTION:In a controller 17, a first estimated car body speed is calculated by a means 30 based on a maximum wheel speed detected by wheel speed sensors 13 - 16 and deceleration detected by a G sensor 12. A second estimated car body speed, reduced at given deceleration from a given value and not influenced by the change of a maximum wheel speed, is calculated by a means 32. When the first estimated car body speed exceeds a given value, a first estimated car body speed is selected by a means 34 and when it is below the given value, the second estimated car body speed is selected thereby. Meanwhile, based on a selected estimated car body speed and wheel speed, the slip ratio of each wheel is calculated by a means 36. During braking, a brake force is controlled by a means 38 so that a calculated slip ratio is adjusted to a target value.