초록 ▼

A limited-slip brake control system includes a basic deceleration control circuit responsive to a wheel deceleration signal and to a selected reference deceleration signal to provide a first brake control signal which is used to modulate brake pressure applied to a braked wheel of a vehicle in order

A limited-slip brake control system includes a basic deceleration control circuit responsive to a wheel deceleration signal and to a selected reference deceleration signal to provide a first brake control signal which is used to modulate brake pressure applied to a braked wheel of a vehicle in order to maintain the vehicle deceleration at a selected reference deceleration representing a level of brake force generally lying in the nonslip portion of a characteristic Mu/slip curve for the vehicle. A large deviation control circuit is also responsive to the wheel deceleration signal and functions to modify the first brake control signal to cause brake pressure to be reduced when the wheel deceleration exceeds a second reference deceleration representing a level of brake force generally lying in a slip portion of the characteristic Mu/slip curve, or, corresponding to a situation where the braked wheel encounters a sudden decrease in the available coefficient of friction and is forced into a skid by the basic deceleration control circuit. A second brake control signal is also provided by the large deviation control circuit when the actual wheel deceleration exceeds a third reference deceleration, higher than the second reference deceleration, signifying that the braked wheel has gone into a deep skid, which second brake control signal is used to immediately reduce brake pressure. An initial skid circuit functions to modify the first brake control signal to minimize or eliminate the tendency of the basic deceleration control circuit to place the braked wheel into a skid upon the initial application of brake pressure, and a dynamic compensation circuit is responsive to the wheel deceleration signal to provide a compensating brake control signal which is combined with the first brake control signal in order to compensate the brake pressure command represented by the first brake control signal for apparent changes in wheel deceleration occasioned by landing gear strut assembly oscillation.

대표청구항 ▼

In a limited-slip brake control system controlling brake force to be developed by a braking means for a wheel of an aircraft, the wheel being supported by a lightly-damped landing gear strut assembly, the limited-slip brake control system being operative to compare measured deceleration of the wheel

In a limited-slip brake control system controlling brake force to be developed by a braking means for a wheel of an aircraft, the wheel being supported by a lightly-damped landing gear strut assembly, the limited-slip brake control system being operative to compare measured deceleration of the wheel with a reference deceleration to obtain a deceleration error signal, and to integrate the deceleration error signal to obtain a brake control signal representing a desired level of brake force, an improvement for compensating the brake control signal for oscillation therein resulting from low-frequency oscillation in the measured wheel deceleration that is produced by the landing gear strut assembly when brake force is developed by the wheel, the improvement comprising a dynamic compensation circuit responsive to measured wheel deceleration for providing a compensating brake control signal having a 90°or greater phase lead for a range of frequencies in the measured wheel deceleration surrounding the expected frequency of oscillation produced by the landing gear strut assembly in the measured wheel deceleration, and a lesser phase lead for all other frequencies in the measured wheel deceleration; and, means for combining said compensating brake control signal with said brake control signal to compensate said brake control signal for said oscillation.