Patents by Inventor Satoshi Ikai

Satoshi Ikai 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).

  • Publication number: 20190115759
    Abstract: A motor drive system includes: a converter connected to a DC link; an inverter for drive connected to the DC link; a power storage device configured to store a DC power from the DC link or supplies a DC power to the DC link; a torque limit value calculation unit configured to calculate a torque limit value of a servomotor for buffer in the power storage device on the basis of a rotation speed of the servomotor for buffer and a DC power amount stored or supplied by the power storage device; and a motor control unit for buffer configured to perform a torque control with respect to the servomotor for buffer while changing an upper limit value and a lower limit value of a torque command using the torque limit value so as to adjust a DC power amount stored or supplied by the power storage device.
    Type: Application
    Filed: October 9, 2018
    Publication date: April 18, 2019
    Applicant: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Publication number: 20190115858
    Abstract: A motor drive system includes: a flywheel; a servomotor for buffer which includes a plurality of independent windings and allows the flywheel to rotate; a plurality of inverters for buffer respectively connected to the windings; a plurality of converters respectively connected to the DC links; inverters for drive which perform power conversion between a DC power in the DC links and an AC power which is a drive power or a regenerative power of the servomotor for drive; and a motor control unit for buffer configured to control driving of the servomotor for buffer by controlling power conversion of the respective inverters for buffer respectively connected to the windings.
    Type: Application
    Filed: October 9, 2018
    Publication date: April 18, 2019
    Applicant: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Patent number: 10261490
    Abstract: A servomotor control device includes: a driven body configured to be driven by a servomotor; a connection mechanism configured to connect the servomotor and the driven body; a position command generation unit configured to generate a position command value; a motor control unit configured to control the servomotor using the position command value; a force estimation part configured to estimate a force estimated value which is a drive force acting on the driven body at a connecting part with the connection mechanism; a force estimated value output part configured to decide on reflection of updating and interruption of updating of a force estimated value based on the position command value, and output either of a force estimated value reflecting updating, or a force estimated value of when interrupting updating; and a compensation amount generation part configured to generate a compensation amount for compensating the position command value.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: April 16, 2019
    Assignee: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Patent number: 10247301
    Abstract: A servo control system including a servo motor, a driven member driven, a coupling mechanism coupled with the servo motor and the driven member, and a motor control part controlling the servo motor. The motor control part includes a position command generating part generating a position command value of the driven member, a force estimating part estimating the drive force acting on the driven member, a compensating part compensating the position command value based on the drive force estimated by the force estimating part, and a control signal output part outputting a control signal to the servo motor based on a position command value compensated by the compensating part.
    Type: Grant
    Filed: November 29, 2013
    Date of Patent: April 2, 2019
    Assignee: FANUC CORPORATION
    Inventors: Yasusuke Iwashita, Kenichi Takayama, Satoshi Ikai
  • Patent number: 10216173
    Abstract: A motor control device includes: a force command unit that designates a force to be applied to a workpiece to be machined by a machining device having a motor as a driving source; a force detecting unit that detects the force applied to the workpiece; a velocity-command calculating unit that calculates a velocity command based on the designated force and the detected force; a torque-command calculating unit that calculates a torque command based on the velocity command and the velocity of the motor; a motor control unit that controls the motor based on the torque command; a determining unit that determines the machining stage of the workpiece based on the detected force; and a gain changing unit that changes at least one of gains individually provided in the velocity-command calculating unit and the torque-command calculating unit in accordance with the determined machining stage.
    Type: Grant
    Filed: May 23, 2017
    Date of Patent: February 26, 2019
    Assignee: FANUC CORPORATION
    Inventors: Tsutomu Nakamura, Satoshi Ikai
  • Patent number: 10189131
    Abstract: A motor control device for a machine tool having a plurality of axes includes a plurality of motor control units that control motors; an abnormality detection unit provided for at least one of the motor control units and configured to output an abnormality detection signal upon detecting an abnormality with respect to the axis driven by the motor controlled by the motor control unit provided with the abnormality detection unit; a safety operation control unit provided for a motor control unit that is not the motor control unit provided with the abnormality detection unit, the safety operation control unit configured to control the motor upon receiving the abnormality detection signal in such a way that the tool comes out of contact with the workpiece; and a communication unit that transmits the abnormality detection signal outputted by the abnormality detection unit to the safety operation control unit.
    Type: Grant
    Filed: October 10, 2017
    Date of Patent: January 29, 2019
    Assignee: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Publication number: 20190025792
    Abstract: A servo motor controller includes: a servo motor; a driven member which is driven by the servo motor and in which a load acting on a drive axis is varied depending on the position of the driven member; a position detection portion and a speed detection portion for the driven member; and a motor control portion, where the motor control portion includes: a position control portion which calculates a speed command based on a positional error between a position command for the driven member and the position FB; a speed control portion which calculates a torque command by multiplying a speed error between the speed command and the speed FB by a speed gain and/or adding a torque offset to the speed error; and a change portion which changes at least one of the speed gain and the torque offset according to the position of the driven member.
    Type: Application
    Filed: July 5, 2018
    Publication date: January 24, 2019
    Inventors: Yuuki KUMAMOTO, Satoshi IKAI
  • Patent number: 10175676
    Abstract: A servomotor controller includes a connection mechanism configured to transfer power of a servomotor to a driven body; a motor control unit configured to control the servomotor using a position command value; a first force estimation unit configured to estimate a first force estimated value which is a drive force acting on the driven body at a connecting unit with the connection mechanism; a second force estimation unit configured to estimate a second force estimated value serving as a fixed value; a selection unit configured to compare an absolute value of the first force estimated value and an absolute value of the second force estimated value to output the first or second force estimated value having the larger absolute value; and a compensation amount generation unit configured to generate a compensation amount for compensating the position command value on the basis of the first or second force estimated value.
    Type: Grant
    Filed: November 29, 2017
    Date of Patent: January 8, 2019
    Assignee: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Publication number: 20190001602
    Abstract: A servo motor controller comprises: a position command generation unit; a position detection unit; a position control unit that generates a velocity command for position control based on a position command and a position FB; a force command generation unit that generates a force command for instructing force to be applied to a subject by a driving target; a force detection unit; a force control unit that generates a velocity command for force control based on the force command and a force FB; a selection unit that selects one of the position control and the force control; and a storage unit that stores a force threshold. The selection unit selects one of the velocity commands for the position control and the force control of a smaller value. If the force FB is smaller than the force threshold, the selection unit selects the velocity command for the position control.
    Type: Application
    Filed: June 5, 2018
    Publication date: January 3, 2019
    Inventors: Satoshi IKAI, Tsutomu NAKAMURA, Tomoyuki AIZAWA
  • Patent number: 10171013
    Abstract: A servomotor control device that performs static friction correction for a servomotor, including: a position control loop for feedback controlling a position of a servomotor; a speed control loop for feedback controlling speed of the servomotor; a position command creation part that creates a position command value for the servomotor; a stop determination part that determines whether or not the servomotor is stopped; a static-friction correction amount calculation part that calculates a static-friction correction amount of the servomotor; and a static-friction correction amount modification part that performs a predetermined modification on the calculated static-friction correction amount, in a case of the servomotor stopping, and then starting to operate in the same direction as prior to stopping.
    Type: Grant
    Filed: November 2, 2017
    Date of Patent: January 1, 2019
    Assignee: FANUC CORPORATION
    Inventors: Ryoutarou Tsuneki, Satoshi Ikai
  • Publication number: 20180373221
    Abstract: A motor controller which controls a servo motor for driving a machine, includes: a speed command unit which commands the speed of the machine; a speed detection unit which detects the speed of the servo motor; and a speed control unit which produces a torque command based on a speed command and a motor speed detected so as to control the speed of the servo motor, where the speed control unit includes a filter which approximates the inverse characteristic of a transmission characteristic from the servo motor to the machine, the filter has a transmission characteristic F(s) based on a frequency ?, a vibration damping coefficient ? and a cutoff frequency ?adj which are adjustment parameters and the frequency ? is adjusted so as to be equal to or more than an antiresonant frequency ?0 of the machine but less than a resonant frequency ?p.
    Type: Application
    Filed: June 12, 2018
    Publication date: December 27, 2018
    Inventors: Tsutomu NAKAMURA, Satoshi IKAI
  • Publication number: 20180373223
    Abstract: To perform reinforcement learning enabling to prevent complicated adjustment of coefficients of backlash compensation and backlash acceleration compensation.
    Type: Application
    Filed: June 4, 2018
    Publication date: December 27, 2018
    Inventors: Satoshi IKAI, Tsutomu NAKAMURA, Tomoyuki AIZAWA
  • Patent number: 10162332
    Abstract: A servomotor control device includes a servomotor; a driven body configured to be driven by the servomotor; a connection mechanism configured to connect the servomotor and driven body, and transmit power of the servomotor to the driven body; a position command generation unit configured to generate a position command value; a motor control unit configured to control the servomotor using the position command value; a position command compensation unit including a force estimation part configured to estimate a drive force acting on the driven body at the connection mechanism, and a compensation amount generation part configured to generate a compensation amount for compensating the position command value based on the estimated drive force; and a restriction part configured to restricting updating of the compensation amount when a command acceleration or a command velocity of the position command value is no more than a desired value.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: December 25, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Publication number: 20180364678
    Abstract: A non-transitory computer readable information recording medium stores an evaluation program for operating first and second motor control units, for evaluating operation characteristics related to a control device including a first motor control unit configured to control a first motor driving a first axis, and a second motor control unit configured to control a second motor driving a second axis. The evaluation program operates the first and second motor control units so that a shape of a movement path of a control target moved by the first and second axes includes at least a cornered shape in which both rotation directions of the first and second motors do not invert, and an arc shape in which one of the first and second motors rotates in one direction, and a rotation direction of the other of the first and second motors inverts.
    Type: Application
    Filed: June 12, 2018
    Publication date: December 20, 2018
    Inventors: Satoshi IKAI, Kenichi TAKAYAMA
  • Publication number: 20180356791
    Abstract: A motor drive system includes a power supply unit configured to supply DC power to a DC link, a servo amplifier for drive configured to convert the DC power in the DC link to AC power and supplies the AC power to the servomotor for drive as a driving power, a power storage device configured to store DC power from the DC link or supplies DC power to the DC link, an abnormality detection unit configured to detect the abnormality of the power storage device, and a control unit configured to, when the abnormality detection unit detects the abnormality of the power storage device, control the operation of the servo amplifier for drive such that the output of the servomotor for drive is limited to a value smaller than the output before the abnormality detection by the abnormality detection unit.
    Type: Application
    Filed: June 1, 2018
    Publication date: December 13, 2018
    Inventors: Shougo SHINODA, Satoshi IKAI
  • Patent number: 10152042
    Abstract: A servomotor control device includes: a servomotor, detection unit, driven body, connection mechanism, and motor control unit, in which the motor control unit includes: a force estimation section that estimates a drive force acting on the driven body at a connection part between the connection mechanism and the driven body; a correction amount generation section that generates a correction amount for correcting the position command value, based on the drive force estimated and a constant for correction; and a rigidity estimation section that gradually increases the constant for correction in a state suspending generation of the position command value, and estimates a magnitude of rigidity of the connection mechanism based on the constant for correction when a variation point occurs in behavior of rotation position information of the servomotor detected, drive force estimated, or correction amount generated.
    Type: Grant
    Filed: April 16, 2018
    Date of Patent: December 11, 2018
    Assignee: FANUC CORPORATION
    Inventors: Shougo Shinoda, Satoshi Ikai
  • Publication number: 20180348727
    Abstract: A servomotor control device includes: a servomotor; a driven body that is driven by the servomotor; a connection mechanism that connects the servomotor and the driven body; a first position detection section that detects a position of the servomotor; a second position detection section that detects a position of the driven body; and a motor control unit, in which the motor control unit includes: a force estimation section that estimates a drive force acting on the driven body at a connection part between the connection mechanism and the driven body; a rigidity estimation section that estimates a magnitude of rigidity of the connection mechanism based on a detected position of the servomotor, a detected position of the driven body, and an estimated drive force; and a rigidity variation detection section that detects a change in rigidity of the connection mechanism, based on the estimated magnitude of rigidity.
    Type: Application
    Filed: June 4, 2018
    Publication date: December 6, 2018
    Inventors: Shougo SHINODA, Satoshi IKAI
  • Publication number: 20180348732
    Abstract: A servomotor control device includes a servomotor, driven body, connection mechanism, first position detection section, second position detection section, and motor control unit. The motor control unit has: a dual position control section that performs semi-closed FB control based on a high-frequency component of a first deviation between a position command value and the position of the servomotor detected by the first position detection section, and full-closed FB control based on a low-frequency component of a second deviation between the position command value and the position of the driven body detected by the second position detection section; an acquisition section that acquires a magnitude of rigidity of the connection mechanism; and a varying section that varies a proportion of the semi-closed FB control to full-closed FB control in the dual position control section, in response to the acquired magnitude of rigidity of the connection mechanism.
    Type: Application
    Filed: June 4, 2018
    Publication date: December 6, 2018
    Inventors: Shougo SHINODA, Satoshi IKAI
  • Publication number: 20180335758
    Abstract: A machine learning device that performs reinforcement learning with respect to a servo control apparatus that controls target device having a motor, including: outputting action information including adjustment information of coefficients of a transfer function of a controller gain to a controller included in the servo control apparatus; acquiring, from the servo control apparatus, state information including a deviation between an actual operation of the target device and a command input to the controller, a phase of the motor, and the coefficients of the transfer function of the controller gain when the controller operates the target device based on the action information; outputting a value of a reward in the reinforcement learning based on the deviation included in the state information; and updating an action-value function based on the value of the reward, the state information, and the action information.
    Type: Application
    Filed: May 10, 2018
    Publication date: November 22, 2018
    Inventors: Shougo SHINODA, Satoshi IKAI
  • Patent number: 10133249
    Abstract: A servomotor controller includes a first and a second converter circuit that perform conversion between AC power of a power supply and DC power, a first inverter circuit that performs conversion between the DC power on the DC side of the first converter circuit and AC power on the side of a first motor, a second inverter circuit that performs conversion between the DC power on the DC side of the second converter circuit and AC power on the side of a second motor, and a power calculation unit that calculates an amount of power of the first motor, wherein control is performed so that the regenerative power of the first motor is supplied to the second motor through the power supply or the regenerative power of the second motor is supplied to the first motor through the power supply, on the basis of the amount of power.
    Type: Grant
    Filed: January 17, 2017
    Date of Patent: November 20, 2018
    Assignee: FANUC CORPORATION
    Inventors: Satoshi Ikai, Kenichi Takayama