Abstract: A method for estimating a friction coefficient of a roadway by a transportation vehicle, wherein a control device of the transportation vehicle receives a first estimated value of a maximum horizontal force from a traction control system that is transmitted to the roadway by a wheel of the transportation vehicle. A control device receives a second estimated value of a wheel contact-patch force of the wheel from a damper controller and calculates the friction coefficient as a vehicle-independent friction coefficient based on the estimated values from the wheel contact-patch force and the horizontal force.

Abstract: A vehicle includes a suspension that supports a front wheel thereon, and a road surface state decision unit that decides a road surface state by detection of an acceleration sensor. The acceleration sensor is provided at a lower portion of the suspension and is capable of detecting an acceleration at least in a one-axis direction. The suspension is a front fork that supports the front wheel of the saddle riding vehicle. The front fork includes a bottom case that connects a lower portion of the front fork and an axle of the front wheel to each other. The acceleration sensor is attached to the bottom case.

Abstract: A roadway condition predictive model that can recommend ameliorative roadway action(s) is disclosed. A roadway controller computer acquires sensor and location information, which describe physical driving surface conditions on the roadway, from a plurality of vehicles that travel on the roadway. The roadway controller computer also acquires environmental and traffic conditions for the roadway. The roadway controller computer creates a predictive model that describes a deterioration rate and future physical condition of the roadway, based on the acquired sensor, location information, environmental and traffic conditions for the roadway. The roadway controller computer then implements an action to ameliorate deterioration of the roadway that is predicted by the predictive model.

Abstract: A computer that includes a processor and memory that stores instructions executable by the processor. The instructions may include generating, at a host vehicle, a roadway friction map by: detecting a velocity change of a target vehicle; calculating friction data based on the velocity change; and storing the friction data.

Abstract: A brake fluid pressure control device for a vehicle includes a wheel speed acquisition device that acquires a wheel speed, an estimated vehicle body speed calculation device that calculates an estimated vehicle body speed on the basis of the wheel speed, and a bad road determination device that determines whether a road surface of travel is a bad road. The brake fluid pressure control device for a vehicle can provide hydraulic control of a brake fluid that is used in wheel brakes, and the bad road determination device determines whether the road surface of travel is a bad road on the basis of the deviation between the estimated vehicle body speed and the wheel speed. The present invention can detect phenomena particular to bad roads, and can more accurately perform bad road determination, and allows for the improvement of control such as ABS control.

Abstract: A control system is provided for an articulated vehicle including a towing vehicle, a trailer and an autonomous emergency braking system, wherein the control system includes: a brake control arrangement adapted to apply a friction-estimating braking; a brake force capacity estimation arrangement adapted to estimate the brake force capacity of the vehicle as a function of longitudinal wheel slip based on the applied friction-estimating braking; an axle load estimation arrangement adapted to estimate the normal force on each wheel axle of the vehicle; a friction estimation arrangement adapted to estimate a friction coefficient based on the estimated brake force capacity and at least one of the estimated normal forces; and a brake strategy adaptation arrangement configured to adapt the brake strategy of the autonomous emergency braking system by adjusting the brake force for at least one wheel axle of the Vehicle based on the estimated friction coefficient and the at least one wheel axle's estimated normal force

Abstract: A system and method for controlling wheel brakes on a trailer in a tractor-trailer are provided. Upon receiving a command to apply a trailer wheel brake, the system determines a speed of the tractor-trailer responsive to a speed signal generated by a vehicle speed sensor. The system also estimates a threshold speed based on a level of friction between the tractor-trailer and a road surface on which the tractor-trailer is travelling. The system then generates a control signal to control delivery of fluid pressure to the trailer wheel brake. The control signal causes delivery of a first fluid pressure to the trailer wheel brake when the speed meets a predetermined condition relative to the threshold speed and a second fluid pressure, less than the first fluid pressure, when the speed does not meet the predetermined condition.

Abstract: A method for monitoring a tire condition includes the following steps: sense a rotational speed of a tire of a moving vehicle via at least one monitoring device of a wireless monitoring system disposed in the vehicle; when the sensed rotational speed reaches a predetermined rotational speed range, obtain a condition of the rotating tire through at least one monitoring device to generate first condition data; compare the first condition data with a plurality of pavement feature data to obtain the corresponding pavement feature data; process with the obtained pavement feature data and the first condition data to filter a pavement feature out of the first condition data, generating second condition data; determine whether the condition of the tire is abnormal based on the second condition data; and send out a warning message when the condition of the tire is determined as being abnormal.

Abstract: A tire contact state estimation method includes: an information acquisition step of acquiring information of the tire; a correlation strength calculation step of calculating a first correlation strength between the rotational velocity and the braking and driving force, and also calculating a second correlation strength between the slip angle and the generated lateral force; a change detection step of detecting whether the first correlation strength has increased or decreased by a first threshold or more with respect to a predetermined first reference value, and also detecting whether the second correlation strength has increased or decreased by a second threshold or more with respect to a predetermined second reference value; and an estimation step of estimating at least two of the following: a condition of a road surface in contact with the tire, a tire internal pressure state, and a tire abrasion state.

Abstract: A vehicle controller includes a camera unit that detects driving conditions of a preceding vehicle; a re-acceleration determiner that determines based on the driving conditions of the preceding vehicle whether or not a re-acceleration state in which the preceding vehicle decelerates and then accelerates occurs; and a rotation controller that, if it is determined that the vehicle is in a re-acceleration state, maintains the engine speed of the engine not less than a lower limit.

Abstract: A motor vehicle control system operable in a steering assist mode in which the system is configured to: detect steering angle; and control a distribution of torque to one or more wheels of the vehicle in dependence on the detected steering angle thereby to induce a turning moment in the direction of turn indicated by the steering angle.

Abstract: Various embodiments of an apparatus and method for determining a wheel end condition are disclosed. In one example, a controller for determining a wheel end condition comprises a plurality of wheel speed sensor inputs for receiving wheel speed sensor signals from a plurality of associated wheel speed sensors installed at associated wheel ends. The controller includes control logic that determines a speed as a function of the wheel speed sensor signal; receives a resistance value of the individual wheel speed sensor and compares the resistance value to a first and second high resistance threshold and a low resistance threshold. The control logic determines a wheel end condition exists at the associated wheel end as a function of the speed and the resistance value.

Abstract: A vehicle and anti-lock braking processes for the vehicle as automatically implemented by a computing device are disclosed. The vehicle can include a perception system and a computing device in communication with the perception system. The computing device can be configured to detect, using the perception system, an environmental condition external to the vehicle and select a wheel slip threshold based on the environmental condition. The environmental condition can be a weather-based condition or an obstacle-based condition. If the selected wheel slip threshold is reached while the vehicle is braking, the computing device can send a command to activate anti-lock braking for the vehicle.

Abstract: A system according to the principles of the present disclosure includes a vibration level module and an engine operation control module. The vibration level module estimates a first level of vibration in a vehicle due to contact between tires of the vehicle and a road surface as the vehicle travels over the road surface. The vibration level module estimates a second level of vibration in the vehicle due to an engine in the vehicle. The engine operation control module selectively adjusts at least one of a speed of the engine and a load on the engine when the second vibration level is less than the first vibration level.

Abstract: A two-wheeled motor vehicle includes a control device and is configured such that a radius of curvature of a cross-section of a tire mounted on one of the front wheel and the rear wheel is larger than a radius of curvature of a cross-section of a tire mounted on the other wheel. The control device includes a sensor arranged to detect a rotation speed of the one wheel, a sensor arranged to detect a rotation speed of the other wheel, and a turn determining section programmed to determine that the vehicle is turning based on a condition that a value corresponding to a bank angle of the vehicle is higher than a threshold. The value corresponding to the bank angle of the vehicle is a value indicating the relative amount of the rotation speed of the one wheel relative to the rotation speed of the other wheel.

Abstract: A brake control system for motor vehicles includes a stability system for stabilizing the vehicle from the standpoint of driving dynamics during braking, a triggering unit for the automatic output of a braking demand as a function of the traffic situation, a braking unit which converts the braking demand into a braking action, and a control unit for modifying the braking demand prior to its implementation as a function of the state of the stability system.

Abstract: A method for ensuring a braking effect utilizes a service brake system and a parking brake system of a vehicle. The service brake system is configured to be actuated irrespective of a driver input, and the parking brake system is activated by an extraneous force, for example in an electromechanical arrangement. When a deceleration request is received, the service brake system is initially actuated. If a deceleration variable remains below a target value and the measured slip is smaller than a slip threshold value, the parking brake system is actuated in order to bring the vehicle to a standstill.

Abstract: In an integrated controller for a vehicle, a main control unit determines whether a road ahead is a split-? road based on captured images obtained by left and right CCD cameras, and, if so, increases a braking intervention distance correction gain for correcting braking intervention distances set by a collision prevention control unit. The collision prevention control unit performs collision prevention control at a brake timing earlier than usual using the braking intervention distances corrected by the correction gain. Furthermore, when the road ahead is determined to be a split-? road, the main control unit decreases a target torque correction gain for correcting a target torque set by an engine control unit to prevent the vehicle from becoming unstable as a result of a yaw moment acting on the vehicle generated by a generated driving force due to a difference in friction coefficient ? between left and right road surfaces.

Abstract: A vehicle control system obtains an index indicating a running condition of a vehicle on the basis of a vehicle parameter indicating a motion of the vehicle and then sets a running characteristic of the vehicle in accordance with the index. The vehicle control system includes a noise reduction unit that is configured to obtain the index on the basis of the vehicle parameter of which a fluctuating component that fluctuates because of a driver's driving operation or the influence of a running road surface.

Abstract: Provided is a vehicle skid control device that avoids a skid erroneous judgment in a high revolution range of a motor. The vehicle skid control device detects the number of revolutions of the motor. When the number of revolutions of the motor is equal to or larger than a predetermined threshold value Nm, the vehicle skid control device prohibits a skid judgment. When the number of revolutions of the motor is smaller than the predetermined threshold value Nm, the vehicle skid control device permits the skid judgment. When the number of revolutions of the motor is equal to or larger than the threshold value Nm, the skid judgment is prohibited. Accordingly, it is possible to avoid the skid erroneous judgment in the high revolution range with the number of revolutions equal to or larger than Nm.

Abstract: Apparatus for estimating a ground contact surface gripping characteristic of a vehicle wheel of a vehicle comprises an input section and an output section. The input section sets an input representing a ratio of a wheel force acting on the vehicle wheel in the ground contact surface, and a wheel slipping degree of the vehicle wheel. The output section determines, from the input, an output representing a grip characteristic parameter indicative of the gripping characteristic of the vehicle wheel.

Abstract: A vehicle motion control apparatus includes hydraulic pressure applying means for applying hydraulic pressure to a wheel cylinder side of any of plural solenoid valves, respectively arranged between a master cylinder and plural wheel cylinders, for the corresponding wheel cylinders even when an operator of the vehicle does not operate a brake operation member, motor controlling means for controlling an output of the electric motor to be reduced in accordance with a condition of a road surface when the hydraulic pressure is applied to the wheel cylinder, and valve controlling means for controlling the operation of the solenoid valve to increase an amount of the brake fluid flown by the operation of the solenoid valve before the output of the electric motor is reduced when the output of the electric motor is controlled to be reduced.

Abstract: A system, method and computer program product is provided for detecting if a vehicle has spun. A normal force and a lateral force of each of a front and rear axle of a vehicle is estimated. A coefficient of friction representative of a surface is estimated. Lateral momenta of the front and rear axles based on the coefficient of friction and the normal and lateral forces is calculated. Whether a surplus momentum is present, is determined. If the surplus momentum is present, a yaw rate of the vehicle is integrated respect to time to obtain a vehicle rotation estimation.

Abstract: A braking control device which adjusts fluid pressure according to the degree of opening of a proportional electromagnetic valve driven at a set drive frequency, and controls a braking force on the basis of the adjusted fluid pressure, comprises a required pressure adjustment precision index setting mechanism for setting a required pressure adjustment precision index on the basis of the precision of pressure adjustment required when the fluid pressure is adjusted according to a required braking force, required operating noise reduction index setting mechanism for setting a required operating noise reduction index on the basis of a requirement to reduce operating noise caused by the drive frequency for driving the proportional electromagnetic valve, and drive frequency setting mechanism for setting the drive frequency of the proportional electromagnetic valve on the basis of the set required pressure adjustment precision index and required operating noise reduction index.

Abstract: Improved methods of controlling the stability of a vehicle are provided via the cooperative operation of vehicle stability control systems such as an Active Yaw Control system, Antilock Braking System, and Traction Control System. These methods use recognition of road surface information including the road friction coefficient (mu), wheel slippage, and yaw deviations. The methods then modify the settings of the active damping system and/or the distribution of drive torque, as necessary, to increase/reduce damping in the suspension and shift torque application at the wheels, thus preventing a significant shift of load in the vehicle and/or improving vehicle drivability and comfort. The adjustments of the active damping system or torque distribution temporarily override any characteristics that were pre-selected by the driver.

Abstract: A method for controlling an antilock brake system on a vehicle, the method comprising calculating a prediction of tire normal forces and modifying a brake torque applied to a brake based on the predicted tire normal forces. The prediction of tire normal forces may be calculated using predicted longitudinal forces or estimates of longitudinal forces that are obtained by predicting a master-cylinder pressure.

Abstract: Disclosed is a method for assisting an operator of a vehicle in adjusting a nominal steering angle at steerable wheels of the vehicle for the vehicle stabilization. An additional steering torque is applied to the steering line of the vehicle, which is determined dependent on a difference between a nominal steering angle and an instantaneous steering angle. The method is characterized in that a value of a load moment acting on the steering line of the vehicle is estimated, and that the additional steering torque is established dependent on the estimated value for the load moment.

Abstract: Each time a prescribed cycle comes to an end, an ECU estimates an average retaining amount of brake fluid in a reservoir of the current prescribed cycle on the assumption that a pump has sucked a constant amount of brake fluid in the current prescribed cycle. The ECU calculates deviation between the average retaining amount at the end of the previous prescribed cycle and the average retaining amount at the end of the current prescribed cycle. The greater the deviation is, the greater a deviation correction amount the ECU sets. The ECU performs deviation pump control in which the target suction amount of the pump is set based on the reference suction amount and the deviation correction amount.

Abstract: An on-board diagnostic system of a vehicle comprises disabling diagnostic operation, such as a misfire monitor, based on road roughness. In one example, the disabling of the diagnostic operation is based on brake actuation and degradation of an anti-lock braking system.

Abstract: A method for estimating the maximum tire/road surface coefficient of friction for a vehicle that includes actively inducing a small amount of acceleration or deceleration to the front wheels or the rear wheels of the vehicle and inducing a corresponding and opposite amount of acceleration or deceleration to the other of the front wheels or the rear wheels of the vehicle so that the acceleration and deceleration cancel each other and the perceived speed of the vehicle does not change. The tire/road surface coefficient of friction and a wheel-slip ratio can be used to determine a road surface condition.

Abstract: According to the present invention, when a target braking/driving force and a vehicle target yaw moment required to a vehicle cannot be achieved through a control of a braking/driving forces of wheels, in a rectangular coordinate of the braking/driving force and the yaw moment, a polygon indicating the maximum range of the braking/driving force and the yaw moment attainable by the braking/driving forces of the wheels, and an ellipse that crosses each side of the polygon and has a major axis and a minor axis aligning with the coordinate axis of the rectangular coordinate are set, for example.

Abstract: A brake control system includes a wheel cylinder, a brake pedal, a master cylinder in which communication between it and an external master cylinder reservoir is cut off when the operating amount of the brake pedal is equal to or greater than a predetermined value, an internal reservoir, and a pump which selectively discharges hydraulic fluid in two directions, one being a direction that increases the hydraulic pressure in the wheel cylinder by drawing up hydraulic fluid from the internal reservoir, and the other being a direction that stores hydraulic fluid in the internal reservoir. The pump is driven to discharge hydraulic fluid in the direction that stores hydraulic fluid when communication is open between the master cylinder and the master cylinder reservoir, and driven to discharge hydraulic fluid in the direction that increases the hydraulic pressure when communication is cut off between the master cylinder and the master cylinder reservoir. A further invention is directed to a brake control method.

Abstract: In an ABS control, a vehicle brake control device detects a sudden change road in which a friction coefficient changes suddenly from a high value to a lower value and controls, based on the detection of the sudden change road, the currents to be supplied to a first and a second electrical motor in a first manner or a second manner, wherein in the first manner the currents are controlled so that the first and second electrical motors would eventually stop rotating if the motor control portion kept controlling the currents in the first manner for a sufficiently long time, and in the second manner the currents are controlled so that the first and second electrical motors would eventually start rotating in a reverse direction if the motor controlling portion kept controlling the currents in the second manner for a sufficiently long time.

Abstract: A vehicle braking apparatus is capable of suppressing time lag at the time of activating an ABS, reliably detecting wheel slippage at a wheel even on a low ? road surface, and performing a brake operation to stop the vehicle without causing stroke variations in a brake actuating unit. A vehicle braking apparatus includes a hydraulic modulator for generating hydraulic pressure applied to a brake caliper which is connected to a master cylinder via a main brake path, and a pressure sensor for detecting hydraulic pressure applied to the brake caliper. When the ABS is activated, the hydraulic pressure applied to the brake caliper is reduced to a pressure reduction target value based on the detected pressure. A normally-open electromagnetic valve lies in the main brake path. The brake path pressure on each side of the valve is equalized by means of the hydraulic modulator before opening the electromagnetic valve.

Abstract: A method for controlling a brake pressure in at least two wheel brakes preferably mounted on one axle of the vehicle, is performed during a braking operation on a road surface having a heterogeneous coefficient of friction. This method works as follows: A low coefficient of friction side and/or a high coefficient of friction side is detected, a stability index representing the driving state of the vehicle is formed, the stability index is evaluated on the basis of the low coefficient of friction side and/or of the high coefficient of friction side and the brake pressure is altered in at least one wheel brake as a function of the value of the stability index and as a function of the result of the evaluation of the stability index on the basis of the low coefficient of friction side and/or the high coefficient of friction side.

Abstract: A method for classifying a road surface condition by estimating the maximum tire/road surface coefficient of friction and actively inducing acceleration or deceleration. In one embodiment, the induced acceleration/deceleration is provided by applying torque to the driven wheels of the vehicle. The speeds of the driven and non-driven wheels are measured. The tire/road surface coefficient of friction and the driven wheel slip ratio are calculated from the wheel speeds. The tire/road surface coefficient of friction and the wheel slip ratio are used to determine the slope of the wheel slip/coefficient of friction curve, which is used to classify the road surface condition.

Abstract: A method, computer usable medium including a program, and a system for braking a vehicle during brake failure. The method and computer usable medium include the steps of determining a brake force lost corresponding to a failed brake, and determining a brake force reserve corresponding to at least one non-failed brake. At least one commanded brake force is determined based on the brake force lost and the brake force reserve. Then at least one command brake force is applied to the at least one non-failed brake wherein at least one of an undesired yaw moment and a yaw moment rate of change are limited to predetermined values. The system includes a plurality of brake assemblies wherein a commanded brake force is applied to at least one non-failed brake.

Abstract: There is provided a braking control device whereby operating noise caused by the drive frequency of the proportional electromagnetic valve can be reduced without reducing the performance of fluid pressure control.

Abstract: When the ABS control is executed by the ABS control portion, the vehicle brake control device calculates the first rotational speeds of the first and second motors necessary to achieve the corresponding pressure increase rates and calculates the second rotational speeds of the first and second motors as the upper limits caused by the unlocking pressure limits. Then the vehicle brake control device controls current values of the currents to be supplied to the first and second motors so that they are rotated in the rotational speeds obtained within a range from the first rotational speeds to the second rotational speeds.

Abstract: In controlling a vehicle, an ECU (anti-lock brake control device) of a brake control device judges a difference in relative length between lock-to-lock time intervals of left and right wheels (step 302), calculates cumulative compensation amounts in dependence on the judged difference (steps 306, 310 to 316), then calculates pressure increase amounts which are brake fluid pressures to be applied respectively to wheel cylinders for the left and right wheels in a pressure increasing mode, in dependence on the cumulative compensation amounts and a base pressure increase amount, and then controls the brake fluid pressures in the pressure increasing mode so that the brake fluid pressures coincide with those so calculated.

Abstract: A method for brake regulation in a vehicle when driving off on a split-? roadway is provided, in which method the presence of a drive-off procedure on a split-? roadway having a high coefficient of friction side and a low coefficient of friction side is recognized, and as a result, the brake pressure on a driven wheel on the high coefficient of friction side of the vehicle is increased.

Abstract: Vehicle stability control system, the system including means for imparting a longitudinal force on the tire and means for calculating the slip parameter GOpt at each activation of the means for imparting a longitudinal force on the tire in the following manner: as the values of Gi are acquired, calculating the variation in G with respect to time, as long as the variation is above a low threshold, calculating coefficients A[wet, p] by direct calculation or by an appropriate regression so as to model variation in G with respect to time by a variation curve which is a function of (Gi, A[wet, p]), as soon as the variation is greater than a high threshold, determining a target slip GCwet using at least the last values of A[wet, p].

Abstract: An improved method and associated system for controlling the brake system of a vehicle train including a tractor vehicle and a trailer vehicle, wherein a control device disposed in the tractor vehicle is adapted to initiate automatic braking of the trailer vehicle, and wherein the conditions of the driving roadway, especially the coefficient of friction, are taken into account in braking of the trailer vehicle. The intensity of braking of the trailer vehicle is reduced by the control device when a coefficient of friction smaller than a predetermined minimum value is detected between the vehicle train or parts thereof and the driving roadway. One application of the invention is in load trains equipped with means for preventing rollover or overturning.

Abstract: A method for electronically regulating brake force distribution to the front axle and the rear axle of a motor vehicle (EBV control), wherein the rotational behavior of the vehicle wheels is determined, compared with the vehicle speed or vehicle reference speed and/or with the changes of these variables, and evaluated to limit the slip on the rear-wheel brakes by modulating the braking pressure. The brake force distribution is controlled in dependence on the sum signals obtained by addition of acceleration values determined on each individual rear wheel and/or by addition of slip values determined on each individual rear wheel. It is particularly arranged for to weight the sum signals with variable sum factors and evaluate them as a criterion for triggering the EBV control (so-called EBV plus control).

Abstract: A brake torque control device obtains inertia torque Tine based upon an equation of motion (Tine=Tw?Ft·Rt) about the rotation of a tire based upon a wheel torque Tw according to a brake torque exerted on the tire, road friction force Ft and a radius Rt of the tire. When the inertia torque Tine exceeds a predetermined reference value, road friction force Ft at this time is set as estimated maximum road friction force Fmax. The instructed brake torque is calculated under the condition that the value that is obtained by adding the predetermined value corresponding to the inertia torque Tine to the torque Fmax·Rt based upon this estimated maximum road friction force Fmax is set as an upper limit value of the instructed brake torque. This allows to clearly set, as one value, the target value of the instructed brake torque upon an ABS control, thereby being capable of more accurately executing the pressure-increasing control and pressure-reducing control of the brake fluid pressure.

Abstract: The frequency of an information signal indicative of a-vibration of a wheel detected by an acceleration sensor mounted to a wheel; or a change in the pressure of a gas in a tire detected by a pressure sensor installed in the tire, is analyzed. The band value of the obtained vibration spectrum or pressure change spectrum is detected, and a vibration level or pressure change level at the detected frequency band is compared with: a vibration level table showing the relationship between road friction coefficient ? and vibration level; or a pressure change level table showing the relationship between road friction coefficient ? and pressure change level, to estimate a road friction coefficient ?. Therefore, it is possible to estimate the value of road friction coefficient ? accurately and improve the safety of a car.

Abstract: A method for cyclically controlling the braking of a vehicle includes the following steps: (a) detecting a road surface frictional force of said vehicle, (b) detecting a brake fluid pressure, and (c) controlling the brake fluid pressure in response to detected values including the brake fluid pressure and the road surface frictional force, the controlling including decreasing the brake fluid pressure in response to the road surface frictional force declining during an increase of the brake fluid pressure and increasing the brake fluid pressure in response to the road surface frictional force declining during fall-off of the brake fluid pressure.

Abstract: A brake gain based torque controller utilizes commanded torque, measured torque and measured pressure in order to provide brake control for a vehicle, such as an aircraft. According to one particular aspect of the invention, the brake gain-based torque controller is provided for controlling a braking operation of a wheel of a vehicle based on a computed brake gain calculated in real-time. Under normal breaking conditions, command torque is multiplied by the calculated computed brake gain to produce a pressure signal to control the pressure to be applied to the brake.

Abstract: In an anti-lock brake system mounted on a vehicle wherein when the vehicle is braked in an emergency during running, an increase in the road surface friction force or road surface friction coefficient owing to an increase in the brake pressure is detected by a road surface friction force detecting device or road surface friction coefficient detecting device. The optimum control start point associated with an increase in the signal value of the road surface friction force F or road surface friction coefficient ? provided by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by using a decrease in the wheel speed, i.e., by using the wheel speed ? or d?/dt. Thereafter, from the point where the specified value of control based on F or ?, or dF/dt or d ?/dt, the brake pressure is moved from the pressure increasing mode to the pressure retaining or decreasing mode.

Abstract: A braking force distribution control device is provided in which wheel speeds of respective wheels of a vehicle are detected. On the basis of the detected wheel speeds, slopes of coefficients of friction ? between the wheels and a road surface are estimated as road surface ? slope values of the respective wheels. On the basis of the estimated road surface ? slope values of the respective wheels, braking forces of the respective wheels are controlled such that the braking forces among the respective wheels are adjusted.