Patents by Inventor Takashi Kodera

Takashi Kodera has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10981598
    Abstract: A control apparatus calculates an axial force deviation, which is a difference between an ideal axial force and an estimated axial force. The ideal axial force is based on a target pinion angle of a pinion shaft configured to rotate in association with a turning operation of steered wheels. The estimated axial force is based on a state variable (such as a current value of a steering operation motor) that reflects vehicle behavior or a road condition. The control apparatus changes a command value for a reaction motor in response to the axial force deviation. For example, the control apparatus includes a basic control circuit configured to calculate a basic control amount, which is a fundamental component of the command value. The basic control circuit changes the basic control amount in response to the axial force deviation. The command value based on the basic control amount reflects the road condition.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: April 20, 2021
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera
  • Patent number: 10933910
    Abstract: A controller controls a steering motor in accordance with a pinion angle command value calculated in response to a steering state. The steering motor produces a driving force to a steering operation mechanism. The controller calculates a target pinion angle in accordance with the steering state and the pinion angle command value by performing feedback control such that an actual pinion angle corresponds to the target pinion angle. The controller includes a compensation control circuit which calculates compensation amounts reflected in the pinion angle command value so as to compensate for an inertia component, a viscosity component, and a spring component of the steering operation mechanism in accordance with the target pinion angle. The compensation control circuit adds the compensation amounts to the target pinion angle so as to calculate the final target pinion angle to be used for the calculation of the pinion angle command value.
    Type: Grant
    Filed: January 24, 2019
    Date of Patent: March 2, 2021
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera
  • Patent number: 10933909
    Abstract: A control apparatus calculates an axial force deviation, which is a difference between an estimated axial force and an ideal axial force based on a target pinion angle of a pinion shaft in association with a turning operation of steered wheels. The estimated axial force is based on a state variable that reflects vehicle behavior or a road condition. The control apparatus includes a steering angle ratio change control circuit configured to calculate a target pinion angle serving as a basis for calculation of the command value. The steering angle ratio change control circuit calculates a speed increasing ratio from a steering angle ratio set based on a vehicle speed and a base gear ratio of a steering mechanism, and calculates a correction angle for a target steering angle by multiplying the speed increasing ratio and the target steering angle together.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: March 2, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Takashi Kodera, Masayuki Kita
  • Publication number: 20210053613
    Abstract: A steering device includes a turning shaft, a steering mechanism, a motor, and a control device. The control device includes a steering-range axial force calculating circuit, a limiting axial force calculating circuit, a final axial force calculating circuit, and an axial force adjusting circuit. The steering-range axial force calculating circuit calculates a steering-range axial force when a steering wheel is operated in a predetermined operation range. The limiting axial force calculating circuit calculates a limiting axial force. The final axial force calculating circuit calculates a final axial force. The axial force adjusting circuit adjusts a value of the steering-range axial force, the limiting axial force, or the final axial force based on the axial force that reflects the force acting on the turning shaft.
    Type: Application
    Filed: August 18, 2020
    Publication date: February 25, 2021
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takashi KODERA, Yoshio KUDO
  • Publication number: 20210053610
    Abstract: A steering control system includes a central processing unit. The central processing unit calculates a plurality of types of axial forces acting on the turning shaft based on a state quantity. The central processing unit calculates a distributed axial force which is used to calculate the command value by summing the plurality of types of axial forces at predetermined distribution proportions. The central processing unit calculates the axial forces to have hysteresis with change of the state quantity. The hysteresis of each axial force is adjusted to approach hysteresis of one specific axial force out of the plurality of types of axial forces.
    Type: Application
    Filed: August 20, 2020
    Publication date: February 25, 2021
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takashi KODERA, Yoshio KUDO
  • Publication number: 20200361525
    Abstract: A steering apparatus includes: a steering mechanism including a turning shaft; a motor configured to give a drive force to the steering mechanism; and a controller configured to control the motor based on a command value. The controller includes a first computation circuit, a second computation circuit and a third computation circuit. The first computation circuit is configured to compute a shaft force that acts on the turning shaft. The second computation circuit is configured to compute a value indicating the degree of intervention in a steering control by a host controller, such that the value gradually changes with respect to time. The third computation circuit is configured to compute a final shaft force, by reflecting the value indicating the degree of the intervention, in the shaft force.
    Type: Application
    Filed: April 29, 2020
    Publication date: November 19, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Patent number: 10807637
    Abstract: A control device controls a reaction force motor that generates a steering reaction force to be applied to a steering mechanism of a vehicle, based on a steering reaction force command value calculated according to a steering state. An axial force distribution calculation circuit of the control device calculates a mixed axial force by summing values obtained by multiplying an ideal axial force and estimated axial forces by individually set distribution rates. The axial force distribution calculation circuit calculates a final axial force to be reflected in the steering reaction force command value, by summing values obtained by multiplying the ideal axial force and the mixed axial force by individually set distribution rates. The axial force distribution calculation circuit sets the distribution rates of the ideal axial force and the mixed axial force, based on a distribution command generated by the host control device when intervening in steering control.
    Type: Grant
    Filed: January 23, 2019
    Date of Patent: October 20, 2020
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera
  • Publication number: 20200324808
    Abstract: A steering control device is configured to control a motor, the motor being a generation source of a driving force that is given to a steering mechanism of a vehicle. The steering control device includes a controller configured to compute a controlled variable depending on a steering state, the controlled variable being used in the control of the motor. The controller is configured to alter a control parameter for the controller, based on a command that is generated by a host control device depending on a purpose of an intervention in a steering control, the host control device being mounted on the vehicle.
    Type: Application
    Filed: April 13, 2020
    Publication date: October 15, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20200283059
    Abstract: A steering control device for a steering system includes an electronic control unit configured to: calculate target torque that is a target value of the motor torque; control operation of the motor; calculate a vehicle speed basic axial force based on a detected vehicle speed; calculate another state quantity basic axial force based on a state quantity other than the detected vehicle speed; calculate a distributed axial force by adding the vehicle speed basic axial force and the other state quantity basic axial force at individually set distribution ratios; calculate the target torque based on the distributed axial force; and reduce the distribution ratio of the vehicle speed basic axial force when the detected vehicle speed is abnormal as compared to when the detected vehicle speed is normal.
    Type: Application
    Filed: February 26, 2020
    Publication date: September 10, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takashi KODERA, Isao NAMIKAWA, Yusuke KAKIMOTO, Yoshio KUDO
  • Patent number: 10759472
    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.
    Type: Grant
    Filed: September 12, 2017
    Date of Patent: September 1, 2020
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera
  • Patent number: 10703405
    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.
    Type: Grant
    Filed: June 15, 2017
    Date of Patent: July 7, 2020
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera
  • Publication number: 20200130739
    Abstract: A controller for a steering device includes an electronic control unit configured to control the steering device. The electronic control unit is configured to acquire an action force and to calculate a basic reaction force based on the acquired action force. The action force includes at least two of axial forces of a plurality of types and a tire force. The axial forces of a plurality of types are applied to a turning shaft that is connected to turning wheels. The tire force is applied to the turning wheels. The electronic control unit is configured to, when one predetermined force of the acquired action force is abnormal, calculate the basic reaction force such that a contribution proportion of the predetermined force to the basic reaction force is lower than a contribution proportion when the predetermined force is not abnormal.
    Type: Application
    Filed: October 25, 2019
    Publication date: April 30, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20200130738
    Abstract: A steering-side control unit includes a steering force component calculation unit that calculates a steering force component, a reaction force component calculation unit that calculates a reaction force component, a target steering angle calculation unit that calculates a target steering angle based on the steering force component and the reaction force component, and a target reaction force torque calculation unit that calculates a target reaction force torque through angle feedback control that makes the steering angle follow the target steering angle. The reaction force component calculation unit includes an end reaction force calculation unit that calculates an end reaction force, and an obstacle contact reaction force calculation unit that calculates an obstacle contact reaction force.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 30, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20200130737
    Abstract: A target reaction force torque calculation unit includes a reaction force component calculation unit that calculates a reaction force component, a target steering torque calculation unit that calculates a target steering torque, a torque feedback control unit that calculates a torque feedback component by performing torque feedback control for making a steering torque follow the target steering torque, a target steering angle calculation unit that calculates a target steering angle, and a steering angle feedback control unit that calculates a steering angle feedback component by performing steering angle feedback control for making a steering angle follow the target steering angle. The target reaction force torque calculation unit calculates a target reaction force torque by adding the torque feedback component and the steering angle feedback component. When an end reaction force exceeds a threshold torque, the torque feedback component is set to zero.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 30, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20200130736
    Abstract: A target assist torque calculation unit (61) includes a target steering torque calculation unit that calculates a target steering torque as a target value of a steering torque, and a torque feedback control unit that calculates a torque feedback component by performing control that makes the steering torque follow the target steering torque. The target steering torque calculation unit calculates the target steering torque having an absolute value that increases as an absolute value of a reaction force component increases. When the reaction force component exceeds a threshold torque, that is, when the absolute value of the target steering torque exceeds a maximum torque detectable by a torque sensor, the target assist torque calculation unit sets the torque feedback component to zero, and sets a target assist torque to zero.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 30, 2020
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20200062294
    Abstract: A controller includes a control circuit configured to calculate a target corresponding steered angle that is a target value of a corresponding steered angle based on the transmission ratio associated with the vehicle speed. The corresponding steered angle is a rotation angle of a rotation shaft, which is convertible to the steered angle whose magnitude is changed relative to a value indicating the steering angle. The control circuit is configured to control the actuation of the motor so that an actual corresponding steered angle is a final target corresponding steered angle that is based on the target corresponding steered angle. The control circuit is configured to calculate the target corresponding steered angle by adjusting the transmission ratio based on a value indicating acceleration or deceleration of a vehicle.
    Type: Application
    Filed: August 21, 2019
    Publication date: February 27, 2020
    Applicants: JTEKT CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takashi KODERA, Masayuki KITA, Toru TAKASHIMA, Tetsuya MORINO
  • Publication number: 20190367083
    Abstract: A steering control apparatus includes an electronic control unit. The electronic control unit computes a first component of a command value. The electronic control unit computes a target rotation angle of a rotatable element based on an input torque. The rotatable element rotates with an operation of the steering wheel. The electronic control unit computes a second component of the command value through feedback control. The electronic control unit computes an ideal axial force based on the target rotation angle. The electronic control unit shifts the ideal axial force as a function of a cross slope, which is a slope in a direction that intersects at right angles with a road, in a specified direction with reference to a neutral value of the ideal axial force, associated with a state where the vehicle travels straight ahead.
    Type: Application
    Filed: May 23, 2019
    Publication date: December 5, 2019
    Applicant: JTEKT CORPORATION
    Inventors: Takashi KODERA, Terutaka TAMAIZUMI, Masayuki KITA, Isao NAMIKAWA
  • Publication number: 20190367079
    Abstract: An input torque fundamental component computation circuit includes: a torque command value computation circuit that computes a torque command value corresponding to a target value for steering torque that is to be input by a driver for drive torque obtained by adding the steering torque to an input torque fundamental component; and a torque F/B control circuit that computes the input torque fundamental component through execution of torque feedback control for causing the steering torque to follow the torque command value. A target steering angle computation circuit computes a target steering angle on the basis of the input torque fundamental component. A steering-side control circuit computes target reaction force torque on the basis of execution of angle feedback control for causing a steering angle to follow a target steering angle. The torque command value computation circuit computes the torque command value in consideration of the grip state amount.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Publication number: 20190367075
    Abstract: A steering control device includes a control unit, and the control unit includes a target steering angle calculating unit configured to calculate a target steering angle based on a steering torque and is configured to calculate a target reaction torque based on execution of feedback control for causing the steering angle to match the target steering angle. The control unit includes a plurality of axial force calculating units configured to calculate a plurality of kinds of axial forces acting on a turning shaft based on different state quantities and a grip state quantity calculating unit configured to calculate a grip state quantity based on the plurality of kinds of axial forces. The target steering angle calculating unit is configured to calculate the target steering angle in consideration of the grip state quantity.
    Type: Application
    Filed: May 29, 2019
    Publication date: December 5, 2019
    Applicant: JTEKT CORPORATION
    Inventor: Takashi KODERA
  • Patent number: 10384711
    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.
    Type: Grant
    Filed: September 13, 2017
    Date of Patent: August 20, 2019
    Assignee: JTEKT CORPORATION
    Inventor: Takashi Kodera