A miniature keyboard wherein the keys are arranged in a way to improve data entry and decrease the chance of depressing multiple keys at a time. Accordingly, the height of the keys are patterned to decrease the chance of multiple key depressions thus increasing the accuracy of data input into the personal digital assistant. In one embodiment, the height of the keys is alternated down the individual rows of keys. In another embodiment, the height of the keys is alternated across individual columns of keys. Similarly, in another embodiment, the heights of the keys are arranged in a checkered pattern on the keyboard. In addition, another embodiment staggers the heights of the keys and incorporates embodiments mentioned above. By incorporating different key arrangements and alternating the height of the keys, key differentiation, key navigation, and data input accuracy is greatly improved due to the improved tactile feedback provided by the miniature keyboard.

Raised keys on a miniature keyboard

A brake force control apparatus having a pump
(100, 102) for pumping up brake fluid from a fluid pressure
passage (26, 28, 42, 44, 46, 48) connecting a master cylinder
(18) and a wheel cylinder (70, 72, 74, 76) is provided which
can accurately detect an amount of brake operation intended
by a driver during execution of a brake assist control. The
brake assist control is achieved by supplying the brake
fluid delivered by the pump (100, 102) to the wheel cylinder
(70, 72, 74, 76) when an emergency brake operation is
performed by a driver. The brake force control apparatus
has a control signal generator and a fluid pressure
controller. The control signal generator generates a
control signal (P M/C *) by compensating a decrease generated
in the output signal (P M/C ) when the pump (100, 102) pumps
up the brake fluid from the fluid pressure passage (26, 28,
42, 44, 46, 48). The fluid pressure controller performs
the brake assist control by using the control signal (*P M/C ).

Brake force control apparatus

When normal braking operation is executed, a master cylinder (32) and wheel cylinders (44FR, 44FL, 44RR, and 44RL) are allowed to communicate. When emergency braking operation is executed, a large braking force is generated by establishing communication between the wheel cylinders (44FR, 44FL, 44RR, and 44RL) and an accumulator (20). When the wheel cylinders and accumulator are allowed to communicate immediately after the emergency braking operation, the pressure increases of the wheel cylinders are obstructed. The wheel cylinders and master cylinders are maintained in communicating states while the pressure of the master cylinder quickly increases even after the emergency braking operation.

Braking force controller

A brake force control device realizes both BA control, in which a great brake force is generated when an emergency braking operation is performed, and ABS control for controlling a slip rate of wheels, and prevents interference between BA control and ABS control. When BA control is judged to be started (step 100, 102), whether ABS control is executed for one or more front wheels (step 104) is judged. In the case where ABS control is executed for one or more front wheels, it is judged that a large amount of liquid pressure will be supplied to wheel cylinders of rear wheels simultaneously with starting of BA control, and BA gradient suppression control for inhibiting inflow of the liquid pressure is started (step 108). In the case where ABS control is not executed on the front wheels, a normal BA control is started (step 106).

Brake force control device

A braking force controlling apparatus changes a magnitude of a braking force produced by a braking operation based on a speed of the braking operation. The braking force controlling apparatus is directed to maintaining a brake-assisting control even when a beginner unintentionally releases a braking operation force on a brake pedal. A hydraulic pressure sensor (40) detects a master cylinder pressure, and a maximum master cylinder pressure during the braking operation of the brake pedal (30) is stored in an ECU (10). When the master cylinder pressure is found to be below a release-judgment level of the master cylinder pressure, which is determined based on the maximum master cylinder pressure, the brake-assisting control is terminated. When the master cylinder pressure is found to be above the release-judgment level, the brake-assisting control is maintained.

Braking force controlling apparatus

In a method for controlling the braking process of a motor vehicle, nonlinear boosting of the braking force is performed if the actuating speed of the brake pedal exceeds a specified trigger threshold value. This trigger threshold value is formed as a function of the instantaneous speed of the motor vehicle, the pedal position of the brake pedal or a variable directly proportional thereto, and of a motor vehicle specific, brake dependent correction value.

Method for controlling the braking process in a motor vehicle

In a method for controlling the braking process of a motor vehicle, nonlinear boosting of the braking force is performed if the actuating speed of the brake pedal exceeds a specified trigger threshold value. This trigger threshold value is dependent on the instantaneous speed of the motor vehicle, the brake pedal position or a variable directly proportional thereto, and of a motor vehicle-specific, brake-dependent correction value. The specification discloses how the correction value is determined from the braking-force input (derived e.g. from pedal travel) and the instantaneously acting braking force (derived e.g. from wheel speed sensors).

Kiesewetter Wolfgang

Papers

Method for controlling the braking process in a motor vehicle

Control of vehicle braking