Abstract: In an electric power steering device which controls an assist motor such that a turning angle of turning wheels approaches a target turning angle set corresponding to steering torque based on an operation of a steering wheel by a driver, pure steering torque is calculated by correcting detection steering torque detected by a torque sensor based on a steering angle detected by a steering angle sensor, and a target turning angle is set based on this pure steering torque. Thereby, influence of moment of inertia and viscous friction of a constituent member on an upstream side of the torque sensor in a steering mechanism, etc. is eliminated, and a correct target turning angle is set. As a result, the turning angle can accurately correspond to the operation of the steering wheel by the driver to attain good drivability.

Abstract: A suspension system for a vehicle, includes (a) a shock absorber disposed between a sprung portion and an unsprung portion and having a damping-force changing mechanism, the shock absorber being configured to generate a damping force with respect to a relative movement of the sprung portion and the unsprung portion such that the magnitude of the damping force is changeable, and (b) a controller configured to control the damping-force changing mechanism. The controller includes a target sprung-speed determining portion configured to determine, as a target sprung speed, a speed of the sprung portion in a behavior of a body of the vehicle that matches an operation input to the vehicle by a driver, for permitting the behavior to match the operation input, the controller being configured to control the damping force such that the speed of the sprung portion becomes equal to the target sprung speed.

Abstract: A steering control apparatus includes: a friction torque setting mechanism setting a friction torque value to be applied to a steering based on information representing a status of a vehicle; a target steering angle setting mechanism setting a target steering angle based on the set friction torque value; an adding friction torque setting mechanism setting an adding friction torque based on a deviation between the set target steering angle and a steering angle; and a steering friction torque controller controlling a friction torque applied to the steering by an actuator based on the set adding friction torque.

Abstract: A shock absorber system, including: a hydraulic shock absorber configured to generate a damping force with respect to a relative movement of a sprung portion and an unsprung portion; a damping-force changer configured to change the damping force; and a controller configured to determine a damping-force index and to control the damping-force changer, wherein the controller is configured to determine, as the index, a required application force to be applied to the sprung portion for damping its movement in an up-down direction, according to a determination rule in which the required application force has the same direction as a direction of a speed of the sprung portion in the up-down direction when the sprung speed is relatively small and acceleration of the sprung portion in the up-down direction is relatively large in a situation in which the direction of the speed and a direction of the acceleration are mutually different.

Abstract: An absorber system for a vehicle includes a controller. The controller determines a reference control amount as a reference of a target control amount which is a target of a control amount for controlling a damping force with respect to an operation of a cylinder in its extension and an operation of the cylinder in its compression. The controller determines the target control amount to the reference control amount for one of the operation of the cylinder in its extension and the operation of the cylinder in its compression and determines the target control amount to a value obtained by multiplying the reference control amount by an extension-compression gain for the other. The controller changes the extension-compression gain in at least one of a driving-stability-emphasized situation in which driving stability is to be emphasized and a ride-comfort-emphasized situation in which ride comfort is to be emphasized.

Abstract: An absorber system for a vehicle includes a controller. The controller determines a reference control amount as a reference of a target control amount which is a target of a control amount for controlling a damping force with respect to an operation of a cylinder in its extension and an operation of the cylinder in its compression. The controller determines the target control amount to the reference control amount for one of the operation of the cylinder in its extension and the operation of the cylinder in its compression and determines the target control amount to a value obtained by multiplying the reference control amount by an extension-compression gain for the other. The controller changes the extension-compression gain in at least one of a driving-stability-emphasized situation in which driving stability is to be emphasized and a ride-comfort-emphasized situation in which ride comfort is to be emphasized.

Abstract: A suspension system for a vehicle, includes (a) a shock absorber disposed between a sprung portion and an unsprung portion and having a damping-force changing mechanism, the shock absorber being configured to generate a damping force with respect to a relative movement of the sprung portion and the unsprung portion such that the magnitude of the damping force is changeable, and (b) a controller configured to control the damping-force changing mechanism. The controller includes a target sprung-speed determining portion configured to determine, as a target sprung speed, a speed of the sprung portion in a behavior of a body of the vehicle that matches an operation input to the vehicle by a driver, for permitting the behavior to match the operation input, the controller being configured to control the damping force such that the speed of the sprung portion becomes equal to the target sprung speed.

Abstract: A shock absorber system, including: a hydraulic shock absorber configured to generate a damping force with respect to a relative movement of a sprung portion and an unsprung portion; a damping-force changer configured to change the damping force; and a controller configured to determine a damping-force index and to control the damping-force changer, wherein the controller is configured to determine, as the index, a required application force to be applied to the sprung portion for damping its movement in an up-down direction, according to a determination rule in which the required application force has the same direction as a direction of a speed of the sprung portion in the up-down direction when the sprung speed is relatively small and acceleration of the sprung portion in the up-down direction is relatively large in a situation in which the direction of the speed and a direction of the acceleration are mutually different.

Abstract: An absorber system for a vehicle includes a controller. The controller determines a reference control amount as a reference of a target control amount which is a target of a control amount for controlling a damping force with respect to an operation of a cylinder in its extension and an operation of the cylinder in its compression. The controller determines the target control amount to the reference control amount for one of the operation of the cylinder in its extension and the operation of the cylinder in its compression and determines the target control amount to a value obtained by multiplying the reference control amount by an extension-compression gain for the other. The controller changes the extension-compression gain in at least one of a driving-stability-emphasized situation in which driving stability is to be emphasized and a ride-comfort-emphasized situation in which ride comfort is to be emphasized.

Abstract: A vehicle body tilting apparatus includes: a right/left-wheels holding member having an elongated shape, and holding a right side wheel and a left side wheel of a vehicle which are disposed to be spaced apart from each other in a width direction of the vehicle such that each of the wheels is movable in a vertical direction; and a lean actuator disposed between the right/left-wheels holding member and a body of the vehicle, and configured to tilt at least the body of the vehicle in a lateral direction with respect to a normal line that is perpendicular to a road surface, by pivoting the right/left-wheels holding member and the body of the vehicle relative to each other. An output shaft of the lean actuator is fixed to the right/left-wheels holding member, and the body of the vehicle is fixed to a main body of the lean actuator.

Abstract: A vehicle body tilting apparatus includes: a right/left-wheels holding member having an elongated shape, and holding a right side wheel and a left side wheel of a vehicle which are disposed to be spaced apart from each other in a width direction of the vehicle such that each of the wheels is movable in a vertical direction; and a lean actuator disposed between the right/left-wheels holding member and a body of the vehicle, and configured to tilt at least the body of the vehicle in a lateral direction with respect to a normal line that is perpendicular to a road surface, by pivoting the right/left-wheels holding member and the body of the vehicle relative to each other. An output shaft of the lean actuator is fixed to the right/left-wheels holding member, and the body of the vehicle is fixed to a main body of the lean actuator.

Abstract: When a change in an output voltage of a main power supply is a decrease, and a degree of the decrease is larger than a reference value, a power supply control portion decreases a boosted voltage of a voltage-boosting circuit according to the degree of the decrease. When the change in the output voltage of the main power supply is an increase, and a degree of the increase is larger than the reference value, the power supply control portion increases the boosted voltage of the voltage-boosting circuit according to the degree of the increase.

Abstract: A vehicle behavior control device (S) determines, by using a vehicle velocity (V), a transmission function (K(s)) which is determined based on a specification of the vehicle, receives as an input a wheel turning speed (?) obtained by differentiating a wheel turning angle (?) of left and right front wheels (FW1, FW2) with respect to time, and outputs a target yaw moment (My). The device (S) also calculates, by using the determined target yaw moment (My), a left-wheel-side forward/backward force (FxCL) imparted to a left wheel side (left front wheel FW1 and left rear wheel RW1) of a vehicle (10) and a right-wheel-side forward/backward force (FxCR) imparted to a right wheel side (right front wheel FW2 and right rear wheel RW2) of the vehicle (10).

Abstract: A vehicle behavior control device (S) determines, by using a vehicle velocity (V), a transmission function (K(s)) which is determined based on a specification of the vehicle, receives as an input a wheel turning speed (?) obtained by differentiating a wheel turning angle (?) of left and right front wheels (FW1, FW2) with respect to time, and outputs a target yaw moment (My). The device (S) also calculates, by using the determined target yaw moment (My), a left-wheel-side forward/backward force (FxCL) imparted to a left wheel side (left front wheel FW1 and left rear wheel RW1) of a vehicle (10) and a right-wheel-side forward/backward force (FxCR) imparted to a right wheel side (right front wheel FW2 and right rear wheel RW2) of the vehicle (10).

Abstract: A vehicle steering apparatus that can prevent a large returning torque from acting when a steering wheel is turned. Through processing of an assist control program, rotational torque (assist torque) of an electric motor is calculated by adding returning torque g·Trto to turning torque Tc (in actuality, subtracting the returning torque g·Trto from the turning torque Tc). The electric motor is driven and controlled in accordance with the calculated assist torque. When the steering torque is large, the calculated returning torque gain g decreases, and therefore, the returning torque g·Trto decreases or becomes zero. With this control, the greater the force (torque) required to operate the steering wheel, the smaller the influence of the returning torque, and steering feel at the time of turning the steering wheel is improved.

Abstract: An electric power steering device, including an electric motor supplied with power from a power supply device to generate a predetermined steering assistance force for a steered wheel, and an assistance control device the controls the amount of electrical power supplied to the electric motor, according to the steering state of a steering wheel. The assistance control device detects the power supply voltage of the power supply device. The assistance control device controls the electrical current supplied to the electric motor, so as to maintain the power supply voltage greater than or equal to a set voltage which is set in advance.

Abstract: A first compensation torque T1, a second compensation torque T2 and a third compensation torque T3 are added to a basic assist torque Tas. In this case, the second compensation torque T2 and the third compensation torque T3 are corrected by multiplying them by a common control gain G that is determined by the steering torque Th and the vehicle speed v. Therefore, since the two compensation control amounts are corrected through multiplication by the common control gain G, no interference occurs between the compensation controls. Besides, when the direction in which the total (T2+T3) of the pre-correction second compensation torque T2 and the pre-correction third compensation torque T3 acts is the same direction as the steering torque Th, the multiplication by the control gain G is avoided.

Abstract: When a change in an output voltage of a main power supply is a decrease, and a degree of the decrease is larger than a reference value, a power supply control portion decreases a boosted voltage of a voltage-boosting circuit according to the degree of the decrease. When the change in the output voltage of the main power supply is an increase, and a degree of the increase is larger than the reference value, the power supply control portion increases the boosted voltage of the voltage-boosting circuit according to the degree of the increase.

Abstract: A target turning angle calculation part 51 calculates a target turning angle ? on the basis of a steering angle ? and a vehicle speed V. A correction turning angle calculation part 52 calculates a transfer function K(s) which is a second transfer function, depending on the vehicle speed V, by using a difference between a transfer function G(s) which is a first transfer function determined on the basis of the specification of the vehicle and a stationary component G(0) of the transfer function G(s), the first transfer function having as an input a turning angle ? and as an output a yaw rate ? of the vehicle, the second transfer function having as an input a target turning rate ?*? obtained by temporally differentiating the target turning angle ?* and as an output a correction turning angle ?c. The correction turning angle calculation part 52 calculates a correction turning angle ?c by multiplying the transfer function K(s) by the target turning rate ?*?.

Abstract: In a power supply apparatus, a power supply circuit includes a primary power supply circuit including a high-voltage battery and a step-down circuit for stepping down the voltage of the high-voltage battery, and a secondary power supply circuit including a low-voltage battery and a step-up circuit for stepping up the voltage of the low-voltage battery. The primary power supply circuit and the secondary power supply circuit are connected in parallel. An output voltage of the secondary power supply circuit is set to be lower than an output voltage of the primary power supply circuit. When the output voltage of the primary power supply circuit becomes lower than a target voltage of the secondary power supply circuit, the voltage stepped-up by the step-up circuit is supplied to a motor drive circuit. Accordingly, power supply backup of an electric power steering apparatus can be performed at low cost.