Abstract: A steering control device can restrain a steering from being operated to cause a steered angle and a steering angle to exceed their upper limit values. A first limiting reaction force setting circuit increases a first reaction force rapidly if the steering angle becomes no smaller than a steering angle threshold. A second limiting reaction force setting circuit increases a second reaction force rapidly if the steered angle becomes no smaller than a steered angle threshold. A target steering angle setting circuit sets a target steering angle based on steering torque applied to the steering minus the first reaction force, the second reaction force, etc. A steering angle control circuit sets reaction torque as a manipulated variable for feedback controlling the steering angle to the target steering angle. An operation signal generation circuit outputs an operation signal to a reaction force motor so as to achieve reaction torque.

Abstract: A steering control device includes a controller configured to execute turning processing of controlling a controlled variable to a command value corresponding to an operation of a steering wheel by controlling a turning-side actuator in a cutoff state, the controlled variable being at least one of a turning angle of the steered wheels and a turning angle rate that is a changing rate of the turning angle; and transmission switching processing of controlling a switching device such that the switching device is switched from the cutoff state to a transmission state on condition that an absolute value of a difference between the controlled variable and the command value continues to be equal to or larger than a threshold when the turning processing is executed.

Abstract: Provided is a steering controller configured to suppress deterioration of the operability of a steering wheel for steering steered wheels even when a driving voltage for a steering system has been decreased. When a clutch is in a disengaged state and steered wheels are steered by a steered-operation actuator while a reaction force is applied to steering wheel by a reaction-force actuator, if a driving voltage for the steered-operation actuator is decreased, a CPU opens relays and stops generation of torque by the steered-operation actuator. Meanwhile, a CPU engages the clutch and steers the steered wheels through cooperation between a steering torque input into the steering wheel and an assist torque generated by a reaction-force motor.

Abstract: Provided is a steering controller configured to switch from an interruption state to a transmission state. In a state where power transmission from the steering wheel to steered wheels is interrupted, a maximum value selection processing circuit outputs a maximum value, out of a steered angle and a steering angle, to a limiting reaction force setting processing circuit. When the absolute value of the maximum value has become equal to or larger than a limitation start threshold value, the limiting reaction force setting processing circuit rapidly increases a limiting reaction force. An operation signal generation processing circuit controls a reaction-force motor to achieve a reaction force command value corresponding to the limiting reaction force. When the absolute value of the maximum value has become equal to or larger than an engagement threshold value, a clutch is engaged to transmit reaction force from the steered wheel-side to the steering wheel.

Abstract: A correction circuit receives a steering torque and an electric signal indicative of an operating state of a clutch. The correction circuit selectively uses a first correction value and a second correction value in accordance with the operating state of the clutch. The first correction value is set to correct deviation of the steering torque relative to its zero point when an exciting coil of the clutch is not energized. The second correction value is set to correct deviation of the steering torque relative to its zero point, caused by magnetic flux generated by energization of the exciting coil of the clutch. Adding the first correction value or the second correction value to the steering torque in accordance with the operating state of the clutch suitably corrects deviation of the steering torque relative to its zero point in accordance with the operating state of the clutch.

Abstract: A steering control device that can more appropriately transmit a road-surface reaction force to a steering wheel is provided. The steering control device feedback controls a steering angle to a target steering angle that is a target value of the steering angle. The steering control device includes an estimated axial force computation circuit that computes an estimated axial force so as to reflect a road-surface reaction force in a reaction force generated by a reaction force actuator. The estimated axial force computation circuit computes the estimated axial force by causing a friction compensation amount computation circuit and an efficiency compensation gain computation circuit to compensate an initial estimated axial force computed by an initial estimated axial force computation circuit.

Abstract: A steering control apparatus includes a steering angle feedback processing unit and an operation signal generation processing unit that operate a reaction force actuator to adjust a steering angle to a target steering angle that is a target value for the steering angle based on feedback control, an ideal-axial-force calculation unit that calculates an ideal axial force, a road-surface-axial-force calculation unit that calculates a road surface axial force, an axial-force allocation calculation unit that calculates a base reaction force in which the ideal axial force and the road surface axial force are allocated in a predetermined ratio, and a target steering angle calculation processing unit that sets a target steering angle based on the base reaction force. The steering angle feedback processing unit feeds back the target steering angle in which road surface information is incorporated through the road surface axial force, so that the steering angle is controlled.

Abstract: A steering control apparatus is provided which enables, when the absolute value of a tire angle increases, suppression of a force that is applied to a steering system and that acts to increase the absolute value of the tire angle. A dq transformation circuit uses a control angle to transform currents flowing through a motor into currents id and iq on a d axis and a q axis. Current feedback control circuits calculate command voltages as manipulative values that are used to feed the currents id and iq back to command currents id* and iq*, respectively. A uvw transformation circuit transforms the command voltages into three-phase command voltages. An angle manipulation processing circuit fixes the control angle when a rotation angle is updated if the absolute value of the tire angle is equal to or larger than a prescribed value.

Abstract: An update amount calculation processing circuit manipulates a control angle based on an update amount in order to perform feedback-control for causing a steering torque to be adjusted to a target torque. In this case, the update amount calculation processing circuit executes a guard process on the update amount with reference to an estimated amount of change that is a speed equivalent value based on estimation by an induced voltage observer. However, when a command current set by a command current setting processing circuit is zero, the update amount calculation processing circuit determines the estimated amount of change subjected to the guard process to be the update amount. When the command current is zero and the update amount is fixed to a guard value, an electric path between the synchronous motor and a battery is blocked.

Abstract: A steering control apparatus is provided which suppresses possible vibration of a steering system resulting from differential steering processing when a steering angle or a steered angle has a large value. A differential steering processing circuit calculates a differential steering correction amount based on a difference value of a target steering angle, and increases or reduces the target steering angle using the calculated amount to obtain a target steered angle. A limiting reaction force setting processing circuit increases a limiting reaction force when a maximum value of the target steering angle and the target steered angle is equal to or larger than a common threshold. When the maximum value approaches the common threshold, an angle-sensitive gain setting processing circuit reduces an angle-sensitive gain so as to correct and reduce the differential steering correction amount.

Abstract: An information processing apparatus is provided for preventing an operator from erroneously rewriting data, by which a process can be performed only by connecting an external storage device to a CPU unit without checking whether a user program in the CPU unit is newer or older than that in the external storage device. For carrying out the present invention, in the information processing apparatus according to the present invention, setting parameters selected from a plurality of setting parameters are set to the external storage device and the CPU unit, and the setting parameters set in the external storage device and the CPU unit are compared.

Abstract: A steering control device can restrain a steering from being operated to cause a steered angle and a steering angle to exceed their upper limit values. A first limiting reaction force setting circuit increases a first reaction force rapidly if the steering angle becomes no smaller than a steering angle threshold. A second limiting reaction force setting circuit increases a second reaction force rapidly if the steered angle becomes no smaller than a steered angle threshold. A target steering angle setting circuit sets a target steering angle based on steering torque applied to the steering minus the first reaction force, the second reaction force, etc. A steering angle control circuit sets reaction torque as a manipulated variable for feedback controlling the steering angle to the target steering angle. An operation signal generation circuit outputs an operation signal to a reaction force motor so as to achieve reaction torque.

Abstract: A steering control device restrains not only a steered angle but also a steering angle from exceeding their upper limit values. A maximum value selection circuit selects a maximum value of a target steered angle and a target steering angle as an end angle and outputs the end angle to a limiting reaction force setting circuit. The limiting reaction force setting circuit increases a limiting reaction force rapidly if the end angle becomes equal to or larger than a common threshold. A target steering angle setting circuit sets a target steering angle based on torque applied to the steering minus the limiting reaction force etc. A steering angle control circuit sets reaction torque as a manipulated variable for feedback controlling the steering angle to the target steering angle. An operation signal generation circuit outputs an operation signal to a reaction force motor so as to achieve the reaction torque.

Abstract: There is provided an electric power steering system that makes it possible to reduce an uncomfortable feeling given to a driver even when current feedback control is executed in a state where a detected steering torque value is held. The electric power steering system includes a torque sensor that outputs a detection signal corresponding to a steering torque; and a controller that controls driving of a motor. The controller computes a detected steering torque value based on the detection signal from the torque sensor, and executes current feedback control for causing an actual current value of the motor to follow a current command value based on the detected steering torque value. When the detected steering torque value is held, the controller makes a feedback gain of the current feedback control smaller than a feedback gain that is used when the detected steering torque value is not held.

Abstract: A steering control apparatus is provided which enables, when the absolute value of a tire angle increases, suppression of a force that is applied to a steering system and that acts to increase the absolute value of the tire angle. A dq transformation circuit uses a control angle to transform currents flowing through a motor into currents id and iq on a d axis and a q axis. Current feedback control circuits calculate command voltages as manipulative values that are used to feed the currents id and iq back to command currents id* and iq*, respectively. A uvw transformation circuit transforms the command voltages into three-phase command voltages. An angle manipulation processing circuit fixes the control angle when a rotation angle is updated if the absolute value of the tire angle is equal to or larger than a prescribed value.

Abstract: There is provided an reliable electric power steering system. The electric power steering system includes a torque sensor that outputs a detection signal corresponding to a steering torque, and a controller. The controller computes a detected steering torque value based on the detection signal, and a torque differential value, which is a first-order time differential value of the detected steering torque value. The controller computes a current command value by providing compensation to a basic current command value based on the detected steering torque value with the use of a compensation value based on the torque differential value. When the detected steering torque value is held for a predetermined period, the controller holds the torque differential value at a value computed before the detected steering torque value is held, during the period in which the detected steering torque value is held.

Abstract: There is provided an electric power steering system that makes it possible to reduce an uncomfortable feeling given to a driver even when a detected steering torque value is held. The controller computes a detected steering torque value based on the detection signal, and provides compensation based on a compensation value to a basic current command value to compute a current command value. The controller executes feedback control for causing a current value of the motor to follow the current command value. The controller executes normal control in which the detected steering torque value is periodically updated and backup control in which periodic updating of the detected steering torque value and holding of the detected steering torque value are alternately executed. The controller switches compensation value between a compensation value used during execution of the normal control and a compensation value used during execution of the backup control.

Abstract: There is provided an electric power steering system that makes it possible to reduce an uncomfortable feeling given to a driver even when a detected steering torque value is held. The controller computes a detected steering torque value based on the detection signal, and provides compensation based on a compensation value to a basic current command value to compute a current command value. The controller executes feedback control for causing a current value of the motor to follow the current command value. The controller executes normal control in which the detected steering torque value is periodically updated and backup control in which periodic updating of the detected steering torque value and holding of the detected steering torque value are alternately executed. The controller switches compensation value between a compensation value used during execution of the normal control and a compensation value used during execution of the backup control.

Abstract: There is provided an reliable electric power steering system. The electric power steering system includes a torque sensor that outputs a detection signal corresponding to a steering torque, and a controller. The controller computes a detected steering torque value based on the detection signal, and a torque differential value, which is a first-order time differential value of the detected steering torque value. The controller computes a current command value by providing compensation to a basic current command value based on the detected steering torque value with the use of a compensation value based on the torque differential value. When the detected steering torque value is held for a predetermined period, the controller holds the torque differential value at a value computed before the detected steering torque value is held, during the period in which the detected steering torque value is held.

Abstract: There is provided an electric power steering system that makes it possible to reduce an uncomfortable feeling given to a driver even when current feedback control is executed in a state where a detected steering torque value is held. The electric power steering system includes a torque sensor that outputs a detection signal corresponding to a steering torque; and a controller that controls driving of a motor. The controller computes a detected steering torque value based on the detection signal from the torque sensor, and executes current feedback control for causing an actual current value of the motor to follow a current command value based on the detected steering torque value. When the detected steering torque value is held, the controller makes a feedback gain of the current feedback control smaller than a feedback gain that is used when the detected steering torque value is not held.