Abstract: In apparatus and method for controlling a vehicular velocity for an automotive vehicle, a vehicular velocity and an inter-vehicle distance from the vehicle to another vehicle which is running ahead of the vehicle are detected, a lateral acceleration imposed on a vehicle body of the vehicle which is generally developed when the vehicle is running on a curved road is detected, a target value of the vehicular velocity of the vehicle according to which a detected value of the inter-vehicle distance is made equal to value of a target inter-vehicle distance is calculated, a correction is made on the calculated value of the target vehicular velocity according to a detected value (magnitude) of the lateral acceleration (lateral G), the vehicular velocity of the vehicle is controlled in such a manner that the detected value of the vehicular velocity is made equal to the corrected target vehicular velocity.

Abstract: A preceding-vehicle follow-up control apparatus is arranged to calculate a target vehicle speed for following-up a preceding vehicle at a target vehicle-to-vehicle distance. The target vehicle speed is calculated from an equation having a form of a linear combination of a form which includes a linear connection between a product of a first gain and a difference between the vehicle-to-vehicle distance and the target vehicle-to-vehicle distance and a product of a second gain and the relative speed. The control apparatus controls a driving apparatus and a transmission apparatus of a vehicle so as to adjust a vehicle speed at the target vehicle speed. This enables the vehicle-to-vehicle distance to be converged into a target value without excessively increasing or decreasing the relative speed during this follow-up control.

Abstract: In an antiskid braking system for increasing or decreasing a braking force according to a wheel speed and a vehicle speed, an algorithm applied to the determination of a braking force decrease amount is improved. Once a target braking force decrease amount is determined according to the wheel speed and vehicle speed, this is compared with a predetermined minimum decrease amount, and when the target decrease amount is less than the minimum decrease amount, braking force is decreased according to the minimum decrease amount. The minimum decrease amount is preferably determined according to the braking force immediately before the braking force decrease. In this way, braking force reduction insufficiencies in several conditions are prevented.

Abstract: A braking force control apparatus for use with an automotive vehicle supported on road wheels each of which has a wheel cylinder for applying a braking force to the corresponding road wheel in response to a fluid pressure introduced thereto. The fluid pressure is controlled by a solenoid valve which is movable between open and closed positions in response to a control signal having a variable duty ratio. The duty ratio of the control signal is changed at predetermined intervals of time to move the solenoid valve in a plurality of steps toward the closed position.

Abstract: In an antiskid brake system that increases or decreases a wheel cylinder pressure according to a wheel speed and vehicle speed, an algorithm applied to pressure increase after pressure decrease is improved. A first target pressure increase amount is computed based on the wheel speed and vehicle speed, and a second target pressure increase amount is computed based on a total pressure decrease amount when pressure is decreased. The wheel cylinder pressure is then increased according to the first target pressure increase amount when an elapsed time from the start of pressure decrease to the start of pressure increase, is longer than a predetermined value, and according to the second target pressure increase amount when the elapsed time is shorter than the predetermined value. In this way, increase of slip amount due to excessive pressure increase is prevented.

Abstract: A control system for an automotive vehicle controls driving torque delivery for driven wheels. The control system basically controls an output torque of an automotive internal combustion engine toward a target engine output torque which is derived on the basis of an accelerator operational magnitude. The target engine output torque can be modified according to associated conditions, such as road friction level, a characteristic of a power train including a torque converter and a power transmission. The control system also performs selection of engine output control and transmission shift control depending upon vehicle driving condition.

Abstract: A system for controlling a fluid pressure such a brake fluid pressure of a vehicle includes a pressure control cylinder having a control piston for varying a pressure of a confined fluid, and a motor for producing a mechanical force for actuating the control piston. To reduce the load of the motor, a hydraulic assist circuit is interposed between the motor and the control piston. The hydraulic assist circuit creates a hydraulic assist pressure by receiving the force of the motor, and converting the assist pressure into a linear motion of the control piston. The mechanical force of the motor is converted to hydraulic assist pressure through a pressurizing piston. The hydraulic assist pressure created by the pressurizing piston is exerted against a working piston. The working piston is connected to the control piston.

Abstract: A system for controlling a fluid pressure includes a pressure modulating cylinder unit having a piston and a cylinder housing defining first and second fluid chambers separated by the piston, a cutoff valve unit for isolating the first and second chambers from a pressure source and from each other, and a motor unit for pushing and pulling the piston to vary the fluid pressure in the first chamber. When the system is used for controlling a brake fluid pressure of a vehicle, the first chamber is connected with a wheel cylinder, and the valve unit is arranged to isolate the wheel cylinder and the first and second chambers from a master cylinder.

Abstract: A system for correcting a wheel speed data produced by a wheel speed sensor, employs a filter for removing noise contained in the output of the wheel speed sensor. The filter limits variation rate of the wheel speed data so as to avoid occurrence of extraordinary variation of wheel speed as influenced by error factors, such as destruction of the wheel speed sensor or noise superimposed on the output of the wheel speed sensor.

Abstract: An anti-skid brake control system is associated with a control system for a power train which controls power train operation mode between a four-wheel drive mode, in which all four wheels are coupled with an automotive internal combustion engine to be distributed torque according to a controlled distribution ratio of an engine driving torque, and a two-wheel drive mode, in which two auxiliary driving wheels are disconnected from the engine to be free from engine driving torque and two driving wheels are connected to the engine to receive the engine driving torque. The anti-skid brake control system is so associated with the power train control system as to normally set the power train operation mode into the two-wheel drive mode during active state of anti-skid brake control, and to set the power train operation mode into the four-wheel driven mode in response to wheel slippage at the primary driving wheels greater than a predetermined threshold value.

Abstract: An anti-skid brake control system comprises a limiter which provides an upper limit of variation of wheel speed indicative data. The limited wheel speed indicative data is derived with respect to each wheel. The greatest limited wheel speed indicative data is selected as vehicle body speed indicative initial data. The anti-skid brake control system derives a projected vehicle body speed indicative data by adding an integrated value of a longitudinal acceleration to the aforementioned vehicle body speed indicative initial data. The integrated value is provided with a predetermined offset value for compensating for error caused in a longitudinal acceleration sensor.

Abstract: An anti-skid brake control system two mutually different mode for projecting the vehicle body speed representative data. In the first mode, the vehicle body speed representative data is derived on the basis of an instantaneous wheel speed data which is latched upon initiation of vehicular braking operation or upon detection of vehicular braking deceleration, and an integrated value of a longitudinal acceleration indicative signal. On the other hand, in a second mode, the vehicle body speed representative data is derived on the basis of the initially latched instantaneous wheel speed data and a fixed value of wheel deceleration gradient data. A first vehicle body speed representative data derived through the first mode of operation and a second vehicle body speed representative data derived through the second mode of operation are selectively used as the vehicle body speed representative data.

Abstract: An anti-skid brake control system for monitoring variation of wheel slippage and whereby detects APPLICATION mode of the anti-skid brake control system and for detecting HOLD mode of the anti-skid brake control. The system comprises a period of time where the operational mode is maintained at HOLD mode condition. When the period to maintain the HOLD mode becomes longer than a predetermined period, than the system set smaller rate for increasing the braking pressure in the subsequent APPLICATION mode.

Abstract: An anti-skid brake control system includes a device for detecting the friction level of a road surface. The system performs mutually different modes of arithmetic operation for deriving wheel acceleration data on the basis of wheel speed monitoring data. Respective modes of arithmetic operations are provided different levels of response characteristics and noise elimination levels adapted for road friction levels. The system selects one of the arithmetic operation modes for deriving the wheel acceleration data depending upon the friction level on the road surface.