Patents by Inventor Kea Hyuk Chang

Kea Hyuk Chang 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).

  • Device and method for fast position control of a hydraulic actuator
    Patent number: 10371018
    Abstract: A method, control system, and variable valve timing system are provided for controlling an actuator that can be switched into an on state and an off state with pulse width modulation. The systems and method include controls configured to determine an actual system parameter on a first time schedule and a desired system parameter on a second time schedule. On a third time schedule, a position error difference between the actual system parameter and the desired system parameter is determined. The third time schedule is configured to begin and to determine the position error difference each time that the actual system parameter is determined and each time that the desired system parameter is determined. A desired duty cycle is determined, and a duty cycle command is sent to a pulse width modulation output unit.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: August 6, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Klaus Pochner, Uwe Steinmann, Kea Hyuk Chang, Scott T Feldmann, Jon C Wasberg
  • DEVICE AND METHOD FOR FAST POSITION CONTROL OF A HYDRAULIC ACTUATOR
    Publication number: 20180274397
    Abstract: A method, control system, and variable valve timing system are provided for controlling an actuator that can be switched into an on state and an off state with pulse width modulation. The systems and method include controls configured to determine an actual system parameter on a first time schedule and a desired system parameter on a second time schedule. On a third time schedule, a position error difference between the actual system parameter and the desired system parameter is determined. The third time schedule is configured to begin and to determine the position error difference each time that the actual system parameter is determined and each time that the desired system parameter is determined. A desired duty cycle is determined, and a duty cycle command is sent to a pulse width modulation output unit.
    Type: Application
    Filed: March 24, 2017
    Publication date: September 27, 2018
    Inventors: Klaus Pochner, Uwe Steinmann, Kea Hyuk Chang, Scott T. Feldmann, Jon C. Wasberg