Abstract: For traction control, different filters, i.e., a hydraulic-pressure-increase filter and a hydraulic-pressure-decrease filter, are provided for increasing and decreasing target pressure, respectively. The inhibiting effect that the hydraulic-pressure-increase filter exhibits with respect to target pressure changes is made less than the inhibiting effect that the hydraulic-pressure-decrease filter exhibits with respect to changes in the target pressure, and so the target pressure is increased quickly but decreased slowly. As such, even if the wheel-cylinder pressure decreases subsequent to the actual wheel-cylinder pressure having increased to follow the target pressure, the wheel-cylinder pressure decreases only gradually, reducing the amount of pressure increase needed to reach the target pressure when the wheel-cylinder pressure is next increased.

Abstract: When driving of a motor is on and W/C pressure of a low-pressure-side wheel is increased, the driving of the motor is continued until the actual W/C pressure of a high-pressure-side wheel in the same system reaches a predetermined range relative to a target pressure. Specifically, if the target pressure of the low-pressure-side wheel is greater than a predetermined value, the braking hydraulic pressure of the low-pressure-side wheel is increased, the motor is driven, and to account for a resulting decrease in the W/C pressure of the high-pressure-side wheel, the driving of the motor is continued until the W/C pressure of the high-pressure-side wheel is restored. Temperature increases in the motor can thereby be prevented and durability can be improved by shortening the drive time of the motor as much as possible.

Abstract: For traction control, different filters, i.e., a hydraulic-pressure-increase filter and a hydraulic-pressure-decrease filter, are provided for increasing and decreasing target pressure, respectively. The inhibiting effect that the hydraulic-pressure-increase filter exhibits with respect to target pressure changes is made less than the inhibiting effect that the hydraulic-pressure-decrease filter exhibits with respect to changes in the target pressure, and so the target pressure is increased quickly but decreased slowly. As such, even if the wheel-cylinder pressure decreases subsequent to the actual wheel-cylinder pressure having increased to follow the target pressure, the wheel-cylinder pressure decreases only gradually, reducing the amount of pressure increase needed to reach the target pressure when the wheel-cylinder pressure is next increased.

Abstract: When driving of a motor is on and W/C pressure of a low-pressure-side wheel is increased, the driving of the motor is continued until the actual W/C pressure of a high-pressure-side wheel in the same system reaches a predetermined range relative to a target pressure. Specifically, if the target pressure of the low-pressure-side wheel is greater than a predetermined value, the braking hydraulic pressure of the low-pressure-side wheel is increased, the motor is driven, and to account for a resulting decrease in the W/C pressure of the high-pressure-side wheel, the driving of the motor is continued until the W/C pressure of the high-pressure-side wheel is restored. Temperature increases in the motor can thereby be prevented and durability can be improved by shortening the drive time of the motor as much as possible.

Abstract: An anti-skid control apparatus comprises an anti-skid control means for controlling a pressure reducing valve and a pressure increasing valve, each of which operated for a target wheel when an anti-skid condition is established for the target wheel, the pressure increasing valve controlled in order to linearly change a pressure difference, an estimating means for estimating an occurrence of a factor by which the brake hydraulic pressure is fluctuated at the conduit connecting the master cylinder to the pressure increasing valve for the target wheel while the pressure increasing valve is controlled for the target wheel, and an output means for generating an output for maintaining the pressure difference during a predetermining time period in which the pressure increasing valve is controlled, when the occurrence of the factor is estimated.

Abstract: A vehicle motion control device is provided. The vehicle motion control device includes a steering angle deviation calculating unit which calculates a steering angle deviation of the vehicle, a frictional coefficient calculating unit which calculates each of road surface frictional coefficients for a traveling road surface of four wheels; and a pressure increasing and reducing controlling unit which performs a split control including applying a pressure increasing limitation of a pressure increasing control in an anti-skid control to a front wheel at a side of the traveling road surface having higher road surface frictional coefficient between the right and left wheels based on an absolute value of the steering angle deviation such that a pressure increasing gradient in the pressure increasing control is smaller as the absolute value is larger.

Abstract: A vehicle motion control device is provided. The vehicle motion control device includes a steering angle deviation calculating unit which calculates a steering angle deviation of the vehicle, a frictional coefficient calculating unit which calculates each of road surface frictional coefficients for a traveling road surface of four wheels; and a pressure increasing and reducing controlling unit which performs a split control including applying a pressure increasing limitation of a pressure increasing control in an anti-skid control to a front wheel at a side of the traveling road surface having higher road surface frictional coefficient between the right and left wheels based on an absolute value of the steering angle deviation such that a pressure increasing gradient in the pressure increasing control is smaller as the absolute value is larger.

Abstract: A vehicle slip state determination system serves to calculate an estimated vehicle speed VB, an estimated vehicle deceleration in the vehicle speed DVB, and each of wheel speed differences between right front and rear wheels and between left front and rear wheels ?VR, ?VL, respectively. The wheel speed difference ?VR, ?VL are divided into three ranges, that is, range 1, range 2, and range 3 by the speed difference upper and lower limit values JVUP and JVLO, each of which is a linear function value with respect to the estimated vehicle deceleration DVB. In the ranges 1 and 3, the vehicle traveling on the road with the low friction coefficient ? is brought into the slip state where four wheels are slipped. If the wheel speed difference at a predetermined estimated vehicle deceleration deviates from a determination range defined by the upper and lower limit values, the slip state of the vehicle, that is, the condition where the vehicle is traveling on the road with the low friction coefficient ? is determined.

Abstract: A lower limit of a target value of a wheel cylinder pressure generated by a wheel cylinder is set as a first value PT1. Specifically, the first value PT1 is determined based on the application pressure generated by the wheel cylinder during an automatic brake control. Accordingly, the actual application pressure generated can be set to be equal to or more than the first value PT1. Thus, it is possible to prevent the application pressure from being decreased unintentionally when the automatic brake control is switched to a manual brake control, and thus, it is possible to maintain a deceleration speed of a vehicle at the level of a vehicle body deceleration generated during the automatic brake control. Accordingly, it is less likely that the driver will be caused to feel a sense of unease by weakening of the braking force.

Abstract: An anti-skid control apparatus comprises an anti-skid control means for controlling a pressure reducing valve and a pressure increasing valve, each of which operated for a target wheel when an anti-skid condition is established for the target wheel, the pressure increasing valve controlled in order to linearly change a pressure difference, an estimating means for estimating an occurrence of a factor by which the brake hydraulic pressure is fluctuated at the conduit connecting the master cylinder to the pressure increasing valve for the target wheel while the pressure increasing valve is controlled for the target wheel, and an output means for generating an output for maintaining the pressure difference during a predetermining time period in which the pressure increasing valve is controlled, when the occurrence of the factor is estimated.

Abstract: A vehicle slip state determination system serves to calculate an estimated vehicle speed VB, an estimated vehicle deceleration in the vehicle speed DVB, and each of wheel speed differences between right front and rear wheels and between left front and rear wheels ?VR, ?VL, respectively. The wheel speed difference ?VR, ?VL are divided into three ranges, that is, range 1, range 2, and range 3 by the speed difference upper and lower limit values JVUP and JVLO, each of which is a linear function value with respect to the estimated vehicle deceleration DVB. In the ranges 1 and 3, the vehicle traveling on the road with the low friction coefficient ? is brought into the slip state where four wheels are slipped. If the wheel speed difference at a predetermined estimated vehicle deceleration deviates from a determination range defined by the upper and lower limit values, the slip state of the vehicle, that is, the condition where the vehicle is traveling on the road with the low friction coefficient ? is determined.

Abstract: A lower limit of a target value of a wheel cylinder pressure generated by a wheel cylinder is set as a first value PT1. Specifically, the first value PT1 is determined based on the application pressure generated by the wheel cylinder during an automatic brake control. Accordingly, the actual application pressure generated can be set to be equal to or more than the first value PT1. Thus, it is possible to prevent the application pressure from being decreased unintentionally when the automatic brake control is switched to a manual brake control, and thus, it is possible to maintain a deceleration speed of a vehicle at the level of a vehicle body deceleration generated during the automatic brake control. Accordingly, it is less likely that the driver will be caused to feel a sense of unease by weakening of the braking force.

Abstract: A jig is successively mounted on each of the four wheels of a vehicle. The jig is struck in three orthogonal directions independently, and at the same time, a microphone inside the vehicle measures the sound pressure of noise generated due to the exciting force. An FFT analyzer operates a frequency response function from the exciting force to the sound pressure. In a drum testing machine, a tire to be subject to noise prediction is mounted on a shaft, the tire is rotated, and the axial force in the three orthogonal directions is measured. The axial force signal is input to the FFT analyzer and the auto power spectrum in the three orthogonal directions and the cross power spectrum between two different axial directions are operated. The frequency response functions are synthesized with the auto power and cross power spectrums, and the power spectrum of the road noise is operated.