Patents by Inventor Masaki Kuwahara

Masaki Kuwahara 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: 11192578
    Abstract: To provide a motor drive control device, an electric power steering device, and a vehicle which can individually diagnose abnormalities of magnetic detection elements, designed in a multisystem configuration to include at least two systems, for each system. A motor drive control device includes two systems of first and second rotation information detection function units. The first and second rotation information detection function units include first and second rotation position information detection units and first and second rotation information detection units. The first and second rotation information detection units individually diagnose their own abnormalities based on first and second motor rotation position signals detected by the first and second rotation position information detection units.
    Type: Grant
    Filed: October 29, 2019
    Date of Patent: December 7, 2021
    Assignee: NSK Ltd.
    Inventors: Masaki Kuwahara, Shigeyuki Uematsu
  • Patent number: 10953885
    Abstract: A road surface detecting apparatus comprises a camera sensor 11 for taking images of a region in front of a vehicle, and an electronic control unit (ECU) configured to: calculate, based on a taken image, parallax information including a parallax of each pixel composing the taken image; extract a pixel corresponding to a road surface from the taken image; acquire, based on information of the extracted pixel, information-indicating-a-road-surface; calculate, based on the information-indicating-a-road-surface, a road surface gradient formula by approximating a gradient of the road surface by a quadratic function; determine whether or not an absolute value of a coefficient of a quadratic term of this formula is greater than a coefficient threshold; and invalidate the information-indicating-a-road-surface when the absolute value is determined to be greater than the threshold.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: March 23, 2021
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Hirotake Ishigami, Naohide Uchida, Ken Tanabe, Masaki Kuwahara
  • Patent number: 10853666
    Abstract: A target object estimating apparatus comprises parallax information calculating means for calculating parallax information including a parallax between corresponding pixels of taken images taken at a same computation timing, road surface region detecting means for detecting a road surface region in the taken image based on the parallax information, road surface region determining means for determining whether or not each pixel in the taken image corresponds to the road surface region, transition information calculating means for calculating transition information including a change amount of a position of each pixel, using temporally sequential taken images, and estimated value calculating means for estimating a position and a speed of a target object by calculating, based on the parallax/transition information, estimated values of the position and the speed of each pixel.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: December 1, 2020
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide Uchida, Ken Tanabe, Hirotake Ishigami, Masaki Kuwahara
  • Patent number: 10810712
    Abstract: In an apparatus for monitoring surroundings of a vehicle based on a plurality of images captured by a plurality of imagers through a windshield of the vehicle, an image acquirer is configured to acquire the plurality of images captured by the plurality of imagers, and a distortion corrector is configured to correct the plurality of images based on an optical distortion distribution of the windshield.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: October 20, 2020
    Assignees: DENSO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA, RICOH COMPANY, LTD.
    Inventors: Toshihiko Terada, Masaki Kuwahara, Hiroaki Ito, Naohide Uchida, Jun Kishiwada
  • Patent number: 10740592
    Abstract: An apparatus comprises three-dimensional object detecting means for detecting a three-dimensional object in a taken image, temporarily determining means for calculating, based on parallax information, a lower end height from a road surface to a lower end of the object, for temporarily determining that the object is a ground-contacting object when the lower end height is less than or equal to a threshold, and for temporarily determining that the object is a floating object when the lower end height exceeds the threshold, and finally determining means for finally determining whether the object is a ground-contacting object or a floating object. The finally determining means finally determines that the object is a ground-contacting object at the current computation timing when the object is determined to be a ground-contacting object in at least one of the temporary determination at the current computation timing and the final determination at the previous computation timing.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: August 11, 2020
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide Uchida, Fumio Sugaya, Ken Tanabe, Hirotake Ishigami, Masaki Kuwahara
  • Patent number: 10690514
    Abstract: A rotation angle detection device includes: a rotating body having magnetic tracks on which magnetic pole pairs are arranged at even intervals in concentric ring shapes; magnetic sensors each configured to detect a magnetic field of a corresponding one of the magnetic tracks and output a sine signal and a cosine signal; storage configured to store magnetic sensor correction information; a correction calculator configured to correct the sine signal and the cosine signal based on the magnetic sensor correction information; a phase detector configured to calculate a phase of the corrected sine signal and the corrected cosine signal; a phase difference detector configured to calculate a phase difference between a plurality of the phases; and an angle calculator configured to convert the phase difference into an absolute angle.
    Type: Grant
    Filed: April 11, 2018
    Date of Patent: June 23, 2020
    Assignee: NSK LTD.
    Inventors: Masaki Kuwahara, Kazuhiro Ohira
  • Publication number: 20200062300
    Abstract: To provide a motor drive control device, an electric power steering device, and a vehicle which can individually diagnose abnormalities of magnetic detection elements, designed in a multisystem configuration to include at least two systems, for each system. A motor drive control device includes two systems of first and second rotation information detection function units. The first and second rotation information detection function units include first and second rotation position information detection units and first and second rotation information detection units. The first and second rotation information detection units individually diagnose their own abnormalities based on first and second motor rotation position signals detected by the first and second rotation position information detection units.
    Type: Application
    Filed: October 29, 2019
    Publication date: February 27, 2020
    Inventors: Masaki KUWAHARA, Shigeyuki UEMATSU
  • Publication number: 20200041308
    Abstract: A rotation angle detection device includes: a rotating body having magnetic tracks on which magnetic pole pairs are arranged at even intervals in concentric ring shapes; magnetic sensors each configured to detect a magnetic field of a corresponding one of the magnetic tracks and output a sine signal and a cosine signal; storage configured to store magnetic sensor correction information; a correction calculator configured to correct the sine signal and the cosine signal based on the magnetic sensor correction information; a phase detector configured to calculate a phase of the corrected sine signal and the corrected cosine signal; a phase difference detector configured to calculate a phase difference between a plurality of the phases; and an angle calculator configured to convert the phase difference into an absolute angle.
    Type: Application
    Filed: April 11, 2018
    Publication date: February 6, 2020
    Applicant: NSK LTD.
    Inventors: Masaki KUWAHARA, Kazuhiro OHIRA
  • Patent number: 10501113
    Abstract: To provide a motor drive control device, an electric power steering device, and a vehicle which can individually diagnose abnormalities of magnetic detection elements, designed in a multisystem configuration to include at least two systems, for each system. A motor drive control device includes two systems of first and second rotation information detection function units. The first and second rotation information detection function units include first and second rotation position information detection units and first and second rotation information detection units. The first and second rotation information detection units individually diagnose their own abnormalities based on first and second motor rotation position signals detected by the first and second rotation position information detection units.
    Type: Grant
    Filed: April 26, 2017
    Date of Patent: December 10, 2019
    Assignee: NSK Ltd.
    Inventors: Masaki Kuwahara, Shigeyuki Uematsu
  • Patent number: 10438367
    Abstract: A parallax calculating apparatus comprises first parallax calculating means for calculating a first parallax on a basis of a reference image for all pixels in the reference image using SGM method, second parallax calculating means for calculating a second parallax on a basis of the reference image for at least a part of pixels among pixels in the reference image using BM method, and final parallax calculating means for calculating a final parallax of each of pixels in the reference image based on the first and second parallaxes. The final parallax calculating means calculates the first parallax as the final parallax for a pixel for which only the first parallax has been calculated and calculates a parallax where a decimal part of the first parallax is replaced with that of the second parallax as the final parallax for a pixel for which the first and second parallaxes have been calculated.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: October 8, 2019
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide Uchida, Ken Tanabe, Hirotake Ishigami, Masaki Kuwahara, Noriaki Shirai
  • Publication number: 20190102869
    Abstract: In an apparatus for monitoring surroundings of a vehicle based on a plurality of images captured by a plurality of imagers through a windshield of the vehicle, an image acquirer is configured to acquire the plurality of images captured by the plurality of imagers, and a distortion corrector is configured to correct the plurality of images based on an optical distortion distribution of the windshield.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 4, 2019
    Inventors: Toshihiko TERADA, Masaki KUWAHARA, Hiroaki ITO, Naohide UCHIDA, Jun KISHIWADA
  • Publication number: 20190100215
    Abstract: A road surface detecting apparatus comprises imaging means 11 for taking an image of a region in front of a vehicle, parallax information calculating means for calculating, based on a taken image, parallax information including a parallax of each pixel composing the taken image, road surface information acquiring means for extracting a pixel corresponding to a road surface from the taken image, and acquiring, based on information of extracted pixel, information-indicating-a-road-surface, road surface gradient formula calculating means for calculating, based on the information-indicating-a-road-surface, a road surface gradient formula by approximating a gradient of the road surface by a quadratic function, gradient change determining means for determining whether or not an absolute value of a coefficient of a quadratic term of this formula is greater than a coefficient threshold, and invalidating means for invalidating the information-indicating-a-road-surface when the absolute value is determined to be greate
    Type: Application
    Filed: September 27, 2018
    Publication date: April 4, 2019
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Hirotake ISHIGAMI, Naohide UCHIDA, Ken TANABE, Masaki KUWAHARA
  • Publication number: 20190102633
    Abstract: A target object estimating apparatus comprises parallax information calculating means for calculating parallax information including a parallax between corresponding pixels of taken images taken at a same computation timing, road surface region detecting means for detecting a road surface region in the taken image based on the parallax information, road surface region determining means for determining whether or not each pixel in the taken image corresponds to the road surface region, transition information calculating means for calculating transition information including a change amount of a position of each pixel, using temporally sequential taken images, and estimated value calculating means for estimating a position and a speed of a target object by calculating, based on the parallax/transition information, estimated values of the position and the speed of each pixel.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 4, 2019
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide UCHIDA, Ken TANABE, Hirotake ISHIGAMI, Masaki KUWAHARA
  • Publication number: 20190102900
    Abstract: A parallax calculating apparatus comprises first parallax calculating means for calculating a first parallax on a basis of a reference image for all pixels in the reference image using SGM method, second parallax calculating means for calculating a second parallax on a basis of the reference image for at least a part of pixels among pixels in the reference image using BM method, and final parallax calculating means for calculating a final parallax of each of pixels in the reference image based on the first and second parallaxes, The final parallax calculating means calculates the first parallax as the final parallax for a pixel for which only the first parallax has been calculated and calculates a parallax where a decimal part of the first parallax is replaced with that of the second parallax as the final parallax for a pixel for which the first and second parallaxes have been calculated,
    Type: Application
    Filed: September 28, 2018
    Publication date: April 4, 2019
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide UCHIDA, Ken TANABE, Hirotake ISHIGAMI, Masaki KUWAHARA, Noriaki SHIRAI
  • Publication number: 20190102602
    Abstract: An apparatus comprises three-dimensional object detecting means for detecting a three-dimensional object in a taken image, temporarily determining means for calculating, based on parallax information, a lower end height from a road surface to a lower end of the object, for temporarily determining that the object is a ground-contacting object when the lower end height is less than or equal to a threshold, and for temporarily determining that the object is a floating object when the lower end height exceeds the threshold, and finally determining means for finally determining whether the object is a ground-contacting object or a floating object. The finally determining means finally determines that the object is a ground-contacting object at the current computation timing when the object is determined to be a ground-contacting object in at least one of the temporary determination at the current computation timing and the final determination at the previous computation timing.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 4, 2019
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DENSO CORPORATION
    Inventors: Naohide UCHIDA, Fumio SUGAYA, Ken TANABE, Hirotake ISHIGAMI, Masaki KUWAHARA
  • Publication number: 20190039645
    Abstract: To provide a motor drive control device, an electric power steering device, and a vehicle which can individually diagnose abnormalities of magnetic detection elements, designed in a multisystem configuration to include at least two systems, for each system. A motor drive control device includes two systems of first and second rotation information detection function units. The first and second rotation information detection function units include first and second rotation position information detection units and first and second rotation information detection units. The first and second rotation information detection units individually diagnose their own abnormalities based on first and second motor rotation position signals detected by the first and second rotation position information detection units.
    Type: Application
    Filed: April 26, 2017
    Publication date: February 7, 2019
    Inventors: Masaki KUWAHARA, Shigeyuki UEMATSU
  • Publication number: 20190041240
    Abstract: A rotation angle detector includes: a multipolar magnet ring magnetized multipolarly along a circumferential direction, at least one magnetic sensor group including three magnetic sensors being placed along the circumferential direction of the multipolar magnet ring, and outputting angle information in association with the rotation of the multipolar magnet ring, the respective pieces of the angle information having a phase difference therebetween of 120 degrees in an electrical angle, and an arithmetic unit configured to calculate a rotation angle of the multipolar magnet ring based on the angle information outputted from the three magnetic sensors included in the magnetic sensor group.
    Type: Application
    Filed: April 19, 2017
    Publication date: February 7, 2019
    Inventor: Masaki KUWAHARA
  • Patent number: 10103657
    Abstract: The motor drive control apparatus includes first and second rotation information detection function units and a power control unit. When it is determined the ignition switch is changed from the ON state to the OFF state, the power control unit intermittently supplies power from a battery to the first and second rotation information detection function units at a first interval while a motor rotation number is lower than a preset rotation number set in advance. When it is determined the motor rotation number becomes equal to or higher than the preset rotation number during this intermittent supply state, the power control unit intermittently supplies the power from the battery to the first and second rotation information detection function units at a second interval shorter than the first interval while the motor rotation number is equal to or higher than the preset rotation number.
    Type: Grant
    Filed: April 26, 2017
    Date of Patent: October 16, 2018
    Assignee: NSK, Ltd.
    Inventors: Masaki Kuwahara, Shigeyuki Uematsu
  • Publication number: 20180234039
    Abstract: The motor drive control apparatus includes first and second rotation information detection function units and a power control unit. When it is determined the ignition switch is changed from the ON state to the OFF state, the power control unit intermittently supplies power from a battery to the first and second rotation information detection function units at a first interval while a motor rotation number is lower than a preset rotation number set in advance. When it is determined the motor rotation number becomes equal to or higher than the preset rotation number during this intermittent supply state, the power control unit intermittently supplies the power from the battery to the first and second rotation information detection function units at a second interval shorter than the first interval while the motor rotation number is equal to or higher than the preset rotation number.
    Type: Application
    Filed: April 26, 2017
    Publication date: August 16, 2018
    Inventors: Masaki KUWAHARA, Shigeyuki UEMATSU
  • Patent number: 10035535
    Abstract: There are provided a relative angle detection device suitable for expanding a torque detection range, and a torque sensor, an electric power steering device and a vehicle including the relative angle detection device. Based on a first sine signal representing sin(?os+??) and a first cosine signal representing cos(?os+??) in accordance with a rotation angle(?is) of a first multipolar ring magnet that synchronously rotates with an input shaft from between the coaxially arranged input shaft and an output shaft, and based on a second sine signal representing sin ?os and a second cosine signal representing cos ?os in accordance with a rotation angle(?os) of a second multipolar ring magnet that synchronously rotates with the output shaft, sin ?? and cos ?? are calculated in accordance with a relative angle(??) between the input shaft and the output shaft, and from ??=arctan(sin ??/cos ??), the relative angle(??) is calculated.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: July 31, 2018
    Assignee: NSK Ltd.
    Inventors: Kazuhiro Ohira, Masaki Kuwahara, Sumio Sugita, Shigeyuki Uematsu