Abstract: The vehicle operation control apparatus multiplies the variable gain G controlled based on the vehicle velocity V, the steering angle &thgr;h, the steering angle velocity &ohgr;h and the actual steering angle &thgr;T with the steering angle &thgr;h, and controls the actual steering angle &thgr;T of the driven wheels on a result of this multiplication. Consequently, the additional turning time gear ratio Ga1 or the turning-back gear ratio Ga2, set up individually, can be selected depending on the turning direction of the steering wheel. Therefore, the steering feeling both at the time of additional turning and turning-back can be improved.

Abstract: This invention provides a vehicle motion control method and a vehicle motion control apparatus capable of improving the behavior stability of a vehicle. According to the vehicle motion control method, vehicle steering characteristic is determined based on a behavior amount differentiated value obtained by differentiating (S203) a slip angle differential value which is a behavior amount of the vehicle which occurs around a z-axis in the vertical direction with respect to the vehicle body (S205, S209). Consequently, because the phase of the slip angle differential value is progressed, the transition tendency of the steering characteristic, that is, which the vehicle motion condition is moved to over-steer or under-steer, can be obtained early. Therefore, the starting timing of the steering control or drive power control of the vehicle can be accelerated thereby improving the behavior stability of the vehicle.

Abstract: An antiskid braking control system includes a wheel factor estimating means for estimating at least a wheel factor such as a side force of a vehicle front wheel and a front wheel slip angle based upon a vehicle state variable, a grip factor estimating means for estimating a grip factor of at least the vehicle front wheel based upon a change of a aligning torque depending upon the front wheel factor, and a control parameter adjusting means for adjusting a control parameter based upon the grip factor estimated.

Abstract: A vehicle control device incorporating an electric power steering is provided, wherein an extraordinary yaw motion acting on a vehicle is detected and is suppressed or moderated, so that the stability of the vehicle in a straight-ahead steering is improved. The causes of the extraordinary yaw motion are one of lateral wind, asymmetrical surface state of the road, lateral slant of the road and the like. A countermeasure against the extraordinary yaw motion is taken by applying a counter (opposite direction) yaw motion on the vehicle or switching over the control mode from a proportional control to a proportional integral control.

Abstract: The present invention is directed to a road condition estimation apparatus for estimating a road condition for use in a vehicle having a steering control unit for actuating a device mechanically independent of a manually operated steering member to steer at least a wheel of front and rear wheels. The apparatus includes an actuating signal detection unit for detecting an actuating signal for actuating the device of the steering control unit, an aligning torque estimation unit for estimating an aligning torque produced on the wheel on the basis of the actuating signal detected by the actuating signal detection unit, and a vehicle state variable detection unit for detecting a state variable of the vehicle.

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 vehicle operation control apparatus multiplies the variable gain G controlled based on the vehicle velocity V, the steering angle &thgr;h, the steering angle velocity &ohgr;h and the actual steering angle &thgr;T with the steering angle &thgr;h, and controls the actual steering angle &thgr;T of the driven wheels on a result of this multiplication. Consequently, the additional turning time gear ratio Ga1 or the turning-back gear ratio Ga2, set up individually, can be selected depending on the turning direction of the steering wheel. Therefore, the steering feeling both at the time of additional turning and turning-back can be improved.

Abstract: This invention provides a vehicle operation control method and vehicle operation control apparatus which protects a vehicle driver from a feeling of disharmony in his steering operation.

Abstract: An antiskid braking control system includes a wheel factor estimating means for estimating at least a wheel factor such as a side force of a vehicle front wheel and a front wheel slip angle based upon a vehicle state variable, a grip factor estimating means for estimating a grip factor of at least the vehicle front wheel based upon a change of a aligning torque depending upon the front wheel factor, and a control parameter adjusting means for adjusting a control parameter based upon the grip factor estimated.

Abstract: The present invention is directed to a wheel grip factor estimation apparatus, which includes a steering factor detection unit for detecting at least one of steering factors including a steering torque and steering effort applied to a steering system extending from a steering wheel to a suspension of a vehicle, an aligning torque estimation unit for estimating an aligning torque produced on at least a wheel of the vehicle on the basis of the steering factor detected by the steering factor detection unit, and a vehicle state variable detection unit for detecting a state variable of the vehicle. The apparatus further includes a wheel factor estimation unit for estimating at least one of wheel factors including a side force and slip angle applied to the wheel on the basis of the vehicle state variable, and a grip factor estimation unit for estimating a grip factor of at least a tire of the wheel, in accordance with a relationship between the estimated alignment torque and the estimated wheel factor.

Abstract: The present invention is directed to a vehicle motion control apparatus, which includes a steering factor detection unit for detecting at least one of steering factors including a steering torque and steering effort applied to a steering system, an aligning torque estimation unit for estimating an aligning torque produced on at least a wheel of the vehicle on the basis of the steering factor, a vehicle state variable detection unit for detecting a state variable of the vehicle, a wheel factor estimation unit for estimating at least one of wheel factors including a side force and slip angle applied to the wheel on the basis of the vehicle state variable, and a grip factor estimation unit for estimating a grip factor of at least a tire of the wheel, in accordance with the estimated alignment torque and the estimated wheel factor.

Abstract: A motor-driven steering controller for controlling a steering wheel of a vehicle. The controller includes a steering torque controlling unit, a braking force estimating unit, a right and left braking force difference estimating unit and an assist steering torque providing unit. The steering torque controlling unit controls a steering torque on the steering wheel depending on a steering operation. The braking force estimating unit estimates braking forces to be imposed on wheels of the vehicle. The right and left braking force difference estimating unit estimates difference between the braking forces to be imposed on the right and left wheels each estimated by the braking forces estimating unit. The assist steering torque providing unit provides an assist steering torque for the steering torque controlling unit on the basis of the difference in braking force between right and left wheels estimated by the right and left braking force difference estimating unit.

Abstract: A vehicle control device incorporating an electric power steering is provided, wherein an extraordinary yaw motion acting on a vehicle is detected and is suppressed or moderated, so that the stability of the vehicle in a straight-ahead steering is improved. The causes of the extraordinary yaw motion are one of lateral wind, asymmetrical surface state of the road, lateral slant of the road and the like. A countermeasure against the extraordinary yaw motion is taken by applying a counter (opposite direction) yaw motion on the vehicle or switching over the control mode from a proportional control to a proportional integral control.

Abstract: A power steering apparatus is provided to generate an assistant force corresponding to a change of viscous friction in the steering unit or the like, without losing information on reaction force from a road surface. An external force calculation portion calculates an external force, that is, a force other than a force for steering (i.e. a steering force) among forces (action forces) acting on the steering unit of a vehicle. The external force is assumed to be composed of an outside force received from the road surface, such as an SAT (self-aligning torque), and an internal drag resulting from a viscous friction generated in the steering unit, and the like and these two forces are separated in an outside force and internal drag calculation portion. In separating these two forces, under the assumption that the outside force is a function of a side slip angle and an internal drag is a function of a steering angular velocity, and coefficients of functions are obtained.

Abstract: A power steering apparatus is provided to generate an assistant force corresponding to a change of viscous friction in the steering unit or the like, without losing information on reaction force from a road surface. An external force calculation portion calculates an external force, that is, a force other than a force for steering (i.e. a steering force) among forces (action forces) acting on the steering unit of a vehicle. The external force is assumed to be composed of an outside force received from the road surface, such as an SAT (self-aligning torque), and an internal drag resulting from a viscous friction generated in the steering unit, and the like and these two forces are separated in an outside force and internal drag calculation portion. In separating these two forces, under the assumption that the outside force is a function of a side slip angle and an internal drag is a function of a steering angular velocity, and coefficients of functions are obtained.