Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: A driving force switching control apparatus in a vehicle which runs by two-wheel drive or four-wheel drive in accordance with the running state. The apparatus includes a device for determining whether the vehicle runs at a constant speed; and a device for determining a drive system of the vehicle running at a constant speed to be the two-wheel drive or the four-wheel drive according to road surface conditions computed using rolling resistance. A threshold value for switching between the two-wheel drive and the four-wheel drive is changed in a manner such that a determination area where the four-wheel drive is selected increases according to increase in the rolling resistance. Sufficient driving force transmitted to the wheels can be secured even when the road surface condition varies, and accordingly, sufficient driving force is secured also when the running condition is changed from constant speed running to acceleration or deceleration running.

Abstract: A system and a method for determining when to update a surface estimation value indicative of a condition of a roadway surface are provided. The method includes determining a front axle cornering force error value based on a predicted front axle cornering force value and a first front axle cornering force value. The method further includes determining a threshold yaw rate error value based on the front axle cornering force error value. The method further includes indicating that the surface estimation value is to be updated when a yaw rate error value is greater than the threshold yaw rate error value.

Abstract: A target resultant force to be applied to a vehicle body is calculated, the magnitude of a critical friction circle of each wheel is estimated, and a critical resultant force is estimated from the estimated magnitude of the critical friction circle. Subsequently, a ratio of the target resultant force to a critical resultant force is set as an effective road friction, and the magnitude of a tire force is set by using the magnitude of the critical friction circle and the effective road friction. The direction of the tire force of each wheel to be controlled is set based on the sum of products, which are calculated for all other wheels, of a distance from the position of the wheel to be controlled to the position of the other wheel in a direction of the resultant force, and the magnitude of the tire force of the other wheel. Cooperative control of steering and braking or steering and driving of each wheel to be controlled is performed based on the magnitude and direction of the tire force which have been set.

Abstract: A method of regulating operation of a hybrid vehicle traveling on a surface having a grade includes determining a drive force of the hybrid vehicle, calculating a brake pressure value and determining whether a grade freeze condition exists based on the brake pressure value. The method further includes calculating a grade value of the surface based on the drive force when the freeze condition does not exist and regulating operation of the hybrid vehicle based on the grade value.

Abstract: A control system for an automotive vehicle (10) and method for operating the same includes a controller (26) that is used to control the brake system in response to an adaptive brake gain coefficient. The adaptive brake gain coefficient may be used by a safety system so that a desired brake torque is applied to the wheel.

Abstract: A road slope determining apparatus for a vehicle includes a slope measuring device that measures a slope of a road on which the vehicle is traveling; a distance measuring device that measures a distance traveled by the vehicle; and a determining apparatus that determines, based on the measured slope and the measured distance traveled, whether the vehicle is traveling on a gradient in which the slope is continuous or on a rough road in which the slope is discontinuous. This road slope determining apparatus is able to appropriately determine whether the road has a slope when the vehicle is traveling at slow speeds such as when running off-road, for example.

Abstract: An aircraft is decelerated by applying a braking force to a wheel of the aircraft as it moves along the ground. An anti skid controller calculates the braking force to be applied by taking into account data relating to the vertical load transmitted between the ground and the wheel and data relating to the slip between the ground and the wheel. Predictions (box 13b) made regarding how the vertical load will change and data (box 13a) concerning the relationship between slip and the ground to wheel friction coefficient are both taken into account when calculating the braking force to be applied. Skids may thereby be predicted in advance and may be reduced or even avoided.

Abstract: A method of estimating the slope of a road surface on which is positioned a motor vehicle. The slope is determined by measuring the velocity and longitudinal acceleration of the vehicle by means of a mathematical model based on the relation Ax={dot over (?)}+g sin ?, where Ax is longitudinal acceleration, {dot over (?)} indicates the component of longitudinal acceleration of the vehicle along the road surface, g is the gravitational acceleration, and ? represents the angle of inclination of the road surface.

Abstract: A braking/driving force fx is calculated at S102, and a lateral force Fy is calculated at S103. At S104, reference is made to a preset map to select a road surface ? estimation part to be used for determination (to select a first road surface ? estimation part 25 or a second road surface ? estimation part 26 or nonperformance of determination. At S105, a display flag Fla from the road surface ? selection part is read. Indication 1 is displayed (S107) in the case of a road having a high ?. Indication 2 is displayed (S109) in the case of a road having a medium ?. Indication 3 is displayed (S111) in the case of a road having a low ?. Indication 0 is displayed (S112) in other cases wherein the road surface ? is unknown.

Abstract: A method and device for detecting and stabilizing a fishtailing trailer using wheel forces. In particular, a method for stabilizing a vehicle combination made up of a towing vehicle and a trailer in which lateral forces acting on at least one wheel or at least one tire are ascertained with the aid of a sensory system that detects wheel forces or tire forces, the existence of a fishtailing movement of the trailer is detected from the ascertained lateral forces and, in the event of a detected fishtailing movement of the trailer, a braking intervention and/or steering intervention is performed.

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: System for controlling the stability of a vehicle, the system comprising 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: determining coefficients A[avg/p] by direct calculation or by an appropriate regression, from a sufficient number of pairs (?i, Gi), so as to model a first curve of variation ?i=f(Gi, A[avg/p]) including the origin, and the pair or pairs (?i, Gi), in which ?i is different from zero, determining an indicator of the average slope ?1 of the first variation curve, determining coefficients B[avg/p] by direct calculation or by an appropriate regression, from a sufficient number of pairs (?i, Gi), so as to model a second variation curve, free not to pass through the origin, ?i=f(Gi, B[avg/p]) including the pair or pairs (?i, Gi), in which ?i is different from zero, determining an indicator of the average slope ?2 of the second variation curv

Abstract: A vehicle motion control apparatus is provided for performing a vehicle stability control on the basis of a parameter indicative of lateral margin for a tire on a road. The apparatus includes a steering control device for controlling a relationship between a steering angle and a tire angle to be varied, and a decelerating control device for controlling a vehicle speed to be decreased. The parameter indicative of lateral margin for the tire is monitored, and the steering control device and the decelerating control device are controlled on the basis of the monitored parameter.

Abstract: An electronic control unit calculates a target yaw rate in accordance with a vehicle speed and a steering angle and calculates the yaw rate difference on the basis of the target yaw rate and an actual yaw rate. The electronic control unit estimates the grip factor of a front wheel to road surface and sets a distribution ratio for distribution of a vehicle-control target value among actuators of a steering system, a brake system, and a drive system in accordance with the estimated grip factor. The electronic control unit controls the actuators of the three systems in accordance with control instruction values distributed on the basis of the vehicle-control target value and the distribution ratio.

Abstract: A comparison/determination part 7 recieves the input of a front wheel speed filtered value ?fF from a front wheel speed filtered value calculation part 5 and a rear wheel speed filtered value ?rF from a rear wheel speed filtered value calculation part 6. It is determined whether the front wheel speed filtered value ?fF has exceeded a preset first threshold C1. It is determined whether the rear wheel speed filtered value ?rF has exceeded a preset second threshold C2 within a time for transmission of vibration from the front wheels to the rear wheels which is experimentally set in advance after the front wheel speed filtered value ?fF exceeded the first threshold C1. The road surface is then determined to be rough when it is determined that the rear wheel speed filtered value ?rF has exceeded the preset second threshold C2.

Abstract: An apparatus (20) for testing the co-efficient of friction of a road surface (78) of a road (79) including an electronic digital device (22) that senses through its sensor (75) the speed of a toothed sprocket wheel (71) and by which through the dropping of a frame (24) by means of a tripping mechanism (80) that trips upon a rotating motor (34) accelerating and by which a predetermined value in device (22) is reached by the speed of a tire flat (61) that strikes road surface (78).

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 control system (18) for an automotive vehicle (10) has a first roll condition detector (64A), a second roll condition detector (64B), a third roll condition detector (64C), and a controller (26) that uses the roll condition generated by the roll condition detectors (64A–C) to determine a wheel lift condition. Other roll condition detectors may also be used in the wheel lift determination. The wheel lift conditions may be active or passive or both.

Abstract: A new automotive (speed control system) safety feature is disclosed. A vehicle with an engaged speed control could be dangerous to drive on a road surface that changes from dry, offering little rolling resistance, to a surface that offers increased resistance to tire rotation. Resistance to tire rotation by water or snow on a road surface will cause an engaged speed control system to try and maintain the set vehicle speed by accelerating the vehicle into the rolling resistance. A driver may lose control of the vehicle in this circumstance if the speed control cannot be disabled immediately. The new safety feature disclosed would automatically disable the vehicle speed control system when the vehicle decelerates due to significant water or snow accumulation on the road surface.

Abstract: A method of determining the grip coefficient ? in the contact area of a tire on a road includes the steps of selecting a plurality of fixed points in space (that is to say ones that are fixed in the reference frame associated with the vehicle) which points lie at different azimuths along the circumference in at least one sidewall of the tire, obtaining a corresponding number of measurements of circumferential distance variation (extension or contraction) at these fixed points when the tire is rolling on the road, and the measurement signals are processed so as to extract the grip coefficient ?.

Abstract: A method for estimation of the maximum grip coefficient on the basis of knowledge of the forces and the self-alignment torque which are generated in the contact area of a tire, includes the steps of: selecting a plurality of fixed points in space, which lie at different azimuths along the circumference in at least one sidewall of the tire, carrying out a corresponding number of measurements of circumferential distance variation (extension or contraction) at these fixed points when the tire is rolling on the road, processing the measurement signals so as to extract the three components of a resultant of forces which are exerted by the road on the contact area of a tire and the self-alignment torque generated by the tire from them, processing the evaluation signals of the three components of a resultant of forces which are exerted by the road on the contact area of a tire and of the self-alignment torque generated by the tire so as to extract the said grip coefficient ? from them.

Abstract: An automatic slowdown control apparatus for a vehicle is disclosed wherein automatic slowdown control can be ended appropriately and automatic slowdown is prevented from being performed excessively on a road of an ascending gradient. The automatic slowdown control apparatus starts automatic slowdown control of rendering a braking mechanism operative to slow down the vehicle when the stability of the posture and/or behavior of the vehicle upon turning is deteriorated. A control end threshold value is set such that the stability of the vehicle is displaced to the instability side as the ascending gradient of the uphill road increases.

Abstract: A correlation coefficient computing unit receives front-left and front-right wheel-accelerations from high-pass filters, each having a driver-operating component removed therefrom, and computes a correlation coefficient therebetween. A computing-unit of upper and lower limits of a correlation coefficient of a population sets upper and lower limits of a correlation coefficient of a population. First and second correction-gain setting units set first and second correction-gains varying in accordance with running and driving states, respectively. A correlation coefficient computing unit of a population computes a correlation coefficient of a population of this time based on the correlation coefficients computed as above, a correlation coefficient of a population of the previous time, the upper and lower limits, and the first and second correction-gains.

Abstract: A steering characteristic control apparatus and method for a vehicle is disclosed which can carry out behavior control of the vehicle regarding a steering characteristic and so forth appropriately in accordance with the type of turning and the road surface situation. To this end, if the steering characteristic of the vehicle is placed into an oversteer or understeer state exceeding a reference level, then the control end condition when the steering characteristic is controlled to the neutral steer side by control of a braking mechanism is set in accordance with an estimated road surface ? state and the type of turning (steady turning or non-steady turning) of the vehicle. Upon steady turning, during traveling on a low ? road, it is set as the control end condition that the stability of the vehicle behavior is restored sufficiently, but during traveling on a high ? road, it is set as the condition that the stability of the vehicle behavior is restored to some degree so that the control can be ended rapidly.

Abstract: The sliding, integral, and proportional controller for providing aircraft antiskid braking control includes a reference velocity subsystem, a velocity error ratio subsystem, and a main controller subsystem generating a control command output signal indicative of a command braking pressure. The main controller subsystem includes a one dimensional sliding mode controller subsystem to determine an estimated net wheel torque signal, an adaptive threshold subsystem for generating an adaptive threshold based upon the modified slip ratio signal and a clock signal, integral gain subsystems, a proportional controller subsystem, and a pressure limiter. A method for determining braking efficiency of an aircraft braking system independent of the specific conditions is also provided.

Abstract: There is provided a deceleration control apparatus for an automotive vehicle, including a target vehicle speed calculation unit that calculates a target vehicle speed and a deceleration control unit that performs deceleration control on the vehicle so that the vehicle reaches the target vehicle speed. The target vehicle speed calculation unit has a first target vehicle speed calculating section to give as the target vehicle speed a first target vehicle speed value by dividing a multiplication product of an estimated road friction coefficient and a predetermined target lateral acceleration limit by a determined actual yaw rate, and a target vehicle speed correcting section to correct the target vehicle speed depending on an accelerator pedal depression and a detected actual lateral acceleration, so as to adjust the amount of deceleration control on the vehicle.

Abstract: The sliding, integral, and proportional controller for providing aircraft antiskid braking control includes a reference velocity subsystem, a velocity error ratio subsystem, and a main controller subsystem generating a control command output signal indicative of a command braking pressure. The main controller subsystem includes a one dimensional sliding mode controller subsystem to determine an estimated net wheel torque signal, an adaptive threshold subsystem for generating an adaptive threshold based upon the modified slip ratio signal and a clock signal, integral gain subsystems, a proportional controller subsystem, and a pressure limiter. A method for determining braking efficiency of an aircraft braking system independent of the specific conditions is also provided.

Abstract: The present invention relates to a method for calculating parameters in a road design of a S type, a complex type and an egg type clothoid, and in particular to a method for calculating a parameter value capable of determining the size of a clothoid that is inserted when designing a S-shaped and interchange, a connection road, etc. in an egg shape. In the present invention, it is possible to easily calculate the clothoid parameter A in a S shape, complex type and egg type road design, and a road design can be fast finished. In addition, in the present invention, it is possible to achieve an easier design of a S shape and egg type clothoid by determining a design specification without using CAD. The design can be achieved based on a simulation using a center coordinate of two circles for achieving an optimum design.

Abstract: The present invention is directed to a vehicle motion control apparatus, which includes a hydraulic pressure regulating device disposed between a master cylinder and a pair of wheel brake cylinders included in each of a dual hydraulic circuit, and a monitor for monitoring state variable of the vehicle. It is determined whether a wheel out of the wheels operatively associated with the pair of wheel brake cylinders is located on the inside of a curve along which the vehicle is turning, or located on the outside of the curve. Also, a state of road holding of the wheel located on the inside of the curve is determined. A desired value for the wheel located on the outside of the curve is set at least on the basis of the road holding determination.

Abstract: A method for the online determination of values of driving dynamics for a motor vehicle. To improve the quality of the control of a motor vehicle and to reduce the demands placed on the driver, the invention discloses a driving dynamics control including the (1) estimated output quantities ?m in dependence on determined or estimated input quantities u and predetermined or predicted vehicle state variables {circumflex over (x)} and optionally further quantities, (2) comparing the estimated output quantities ?m with measured output quantities ym, and (3) determining the estimated driving dynamics quantities {circumflex over (x)}(tk/tk) in dependence on the measurement result and, as the case may be, further criteria.

Abstract: In a method for determining the state of a road during driving of a motor vehicle, the sound which is generated when a vehicle tire rolls on an underlying surface is sensed. A frequency signal is determined by means of a sound level signal which describes the sound, and is divided into at least two sub-zones by means of at least one limiting frequency. The sub-zones are each assigned to an associated frequency band, and an intensity value is determined for each of at least two frequency bands from the assigned sub-zone of the frequency signal. The intensity value is characteristic of the sound intensity which is present in a frequency band. An intensity ratio is formed from two intensity values by dividing the first intensity value of the first frequency band by the second intensity value of the second frequency band, and is used to determine the state of a road.

Abstract: The present invention is directed to a road condition estimation apparatus for estimating a road condition for use in a vehicle having steering control unit for actuating a device mechanically independent of a manually operated steering member to steer each wheel.

Abstract: The aim is to stably control the lateral movement of a vehicle even on a road where the frictional coefficient is extremely small, such as on a frozen road, thereby improving the turnability and travelling stability. The device includes a frictional force adding means for increasing the frictional force of wheels to a road surface by scattering particulates and a controller which calculates the target lateral movement value and the actual lateral movement value based on the signals from wheel speed sensors, a steering angle sensor and a yaw rate sensor and actuates the right or left frictional force adding means according to the difference between these two values to increase the frictional force, thereby stabilizing the lateral movement.

Abstract: It is checked based on entered information as to whether a vehicle should be decelerated or not (S106). When the vehicle should decelerate, an automatic brake operation is carried out with a braking force being set to be smaller by a predetermined ratio than an estimated maximum braking force estimated based on a road surface friction coefficient ?(S110).

Abstract: A SAT estimating portion supplies a grip degree estimating portion with the estimated SAT value. A summing device sums a front wheel slip angle on which high pass filter processing has been performed and a front wheel slip angle on which low pass filter processing has been performed so as to obtain an integrated slip angle. A grip degree estimating portion estimates a grip degree of a tire, by calculating a SAT reference value which is based on the integrated slip angle, and calculating a ratio between the SAT reference value and the estimated SAT value. A road surface ? value estimating portion estimates a road surface ? value when the grip degree becomes equal to or lower than a reference value.

Abstract: A vehicle traction control system is actuated when driven wheel slip (S1) exceeds a predetermined slip threshold (Ts) to reduce the amount of driven wheel slip (S1) by reducing the driven wheel speed. The traction control system also monitors vehicle deceleration. Upon detecting that the vehicle is decelerating and that the vehicle deceleration has exceed a deceleration threshold, the traction control system determines that the vehicle has encountered a deformable surface such as mud or deep snow. Upon detecting entry onto a deformable surface, the slip threshold (Ts) is linearly increased over a period of time to increase the driven wheel speed and thereby allow the wheels to churn through the deformable surface.

Abstract: A physical quantity estimating apparatus and method that detects an acceleration and deceleration rate of a vehicle body and a rotational velocity of a wheel, estimates at least one of a tire radius of each wheel, a road surface ? gradient, and a spring constant of a combination spring which combines spring elements, with a distribution ratio of braking force and driving force to a front and rear wheel and a distribution ratio of a load on each wheel that is corrected according to the detected acceleration and deceleration rate, as known values, based on a wheel speed difference of any two wheels, during acceleration and deceleration of a vehicle, of an ideal vehicle model that takes into consideration a tire torsional spring element and a suspension longitudinal spring element and estimates a tire type based on the estimated road surface ? gradient and spring constant.

Abstract: A method and an apparatus for regulating the speed of the low-? wheel as a vehicle starts from rest or accelerates on a road surface having adhesive friction values that differ between the left and right sides of the vehicle (split-?), the low-? wheel being braked by braking intervention when it has exceeded a defined slip threshold.

Abstract: An improved anti-lock control method for a vehicle brake system identifies various factors that degrade the effectiveness of the brake system and adaptively adjusts a brake apply rate during anti-lock brake control to compensate for the identified degradation so that the optimal tractive force during anti-lock brake control is more nearly realized. The identified factors include fading due to brake heating, hydraulic leakage, mis-adjusted and non-releasing rear brakes, brake wear and excessive vehicle weight.

Abstract: A rollover detection system (12) for an automotive vehicle (10) includes a controller (14) that is hooked to various types of sensors. The sensors may include a lateral acceleration sensor and another sensor or combination of sensors that gives an indication to another lateral condition of the vehicle. The controller determines a roll condition in response to comparing the lateral acceleration and the lateral condition other than lateral acceleration to a threshold. When the conditions are above the threshold then a roll condition is indicated. When a roll condition is indicated a safety device (40) may be controlled to prevent rollover and/or deploy a safety device.

Abstract: Disclosed herein is a method of controlling traveling stability of a vehicle. In the present invention, a driver's desired yaw rate is estimated using a steering wheel angle and a reference speed of the vehicle while turning. The condition of a road surface the vehicle is traveling on is judged by comparing lateral acceleration of the vehicle, estimated using the estimated yaw rate and a reference vehicle speed, with lateral acceleration actually measured by a lateral acceleration sensor. A driver's desired reference yaw rate is determined according to the judged road surface condition. It is determined whether a vehicle is understeered or oversteered by comparing the determined reference yaw rate with an actual yaw rate measured by a yaw rate sensor. According to the determined result, braking force and driving force of the vehicle are controlled, thus obtaining excellent vehicle stability.

Abstract: An electric power steering apparatus for applying an assisting steering force to a steering mechanism of a vehicle by driving an electric motor according to a steering operation includes: an electric current command value calculation unit which calculates an electric current command value; a drive control unit which controls the drive of the electric motor based on the electric current command value; and a convergence control unit which determines a damping compensation value so that a quantity of steering operation is converged to a neutral point. The convergence control unit includes: a compensation electric current setting unit determines a basic damping compensation electric current value corresponding to the correction value of the target value, and a compensation electric current adjusting unit which adjusts the basic damping compensation electric current value based on the steering torque and the quantity of the steering operation, thereby calculating the damping compensation value.

Abstract: Steering stability of a vehicle under a traveling state such as cornering is enhanced by controlling a state of the vehicle based on cornering powers of right and left wheels. A detecting unit 1 detects action force containing longitudinal force Fx, lateral force Fy and vertical force Fz which act on each wheel. A specifying unit 2 specifies a friction coefficient between the wheels and road surface. An estimating unit 6 estimates cornering power ka of each wheel based on the action force and the friction coefficient. A processing unit 7 determines control values so that the representative value ka_ave of the cornering powers concerning the right and left wheels is larger than the present value of the representative value ka_ave of the cornering powers concerning the right and left wheels. Controlling units 8 to 10 control the state of the vehicle based on the control values thus determined.

Abstract: A traction control system having a braking intervention in particular for motor vehicles in which a slipping wheel is braked by a braking intervention on exceeding a slippage threshold. To improve the stability and steerability of the vehicle on slopes having different adhesive friction values between the right and left sides of the vehicle (&mgr;-split), the slippage threshold of the slipping low-&mgr; wheel is adjusted as a function of the slope, the slippage threshold of the slipping wheel being increased with an increase in slope in the case of a front-wheel drive vehicle and is decreased with an increase in slope in the case of a rear-wheel drive vehicle.

Abstract: An apparatus and method for detecting the road condition for use in a motor vehicle. The system and method detect road data through a temperature sensor, an ultrasonic sensor, and a camera. The road data is filtered for easier processing. A comparison of the filtered road data to reference data is made, and a confidence level of that comparison is generated. Based on the comparison of filtered road data to reference data, the road condition is determined. The driver may be informed and/or stability control systems may be adjusted based on the detected road surface condition.

Abstract: An apparatus and method for detecting the road condition for use in a motor vehicle. The system and method detect road data through a temperature sensor, an ultrasonic sensor, and a camera. The road data is filtered for easier processing. A comparison of the filtered road data to reference data is made, and a confidence level of that comparison is generated. Based on the comparison of filtered road data to reference data, the road condition is determined. The driver may be informed and/or stability control systems may be adjusted based on the detected road surface condition.

Abstract: An SAT estimating section estimates self-aligning torque (SAT) on the basis of a steering torque, which is detected by a steering torque detecting section, and an assist torque, which is detected by an assist torque detecting section. An SAT model value computing section computes an SAT model value by using an integrated slip angle &agr;I. An SAT ratio/drift amount computing section computes, by on-line identification, a ratio (SAT ratio) of the SAT to the SAT model value, and a drift amount of a lateral acceleration sensor.

Abstract: A target resultant force to be applied to a vehicle body is calculated, the magnitude of a critical friction circle of each wheel is estimated, and a critical resultant force is estimated from the estimated magnitude of the critical friction circle. Subsequently, a ratio of the target resultant force to a critical resultant force is set as an effective road friction, and the magnitude of a tire force is set by using the magnitude of the critical friction circle and the effective road friction. The direction of the tire force of each wheel to be controlled is set based on the sum of products, which are calculated for all other wheels, of a distance from the position of the wheel to be controlled to the position of the other wheel in a direction of the resultant force, and the magnitude of the tire force of the other wheel. Cooperative control of steering and braking or steering and driving of each wheel to be controlled is performed based on the magnitude and direction of the tire force which have been set.

Abstract: A control system for an automotive vehicle having a vehicle body includes a sensor cluster having a housing oriented within the vehicle body. A roll rate sensor is positioned within the housing and generates a roll rate sensor signal corresponding to a roll angular motion of the sensor housing. A controller receives the roll rate sensor signal, the controller generates a residue signal in response to a sensor error or a measurement error. The controller sets a fault condition in response to the residue signal larger than a dynamic threshold and a magnitude of the roll rate signal above a fault condition threshold. The controller sets a fault flag in response to the fault condition indicated for a predetermined time during which no double wheel lift occurs.