Patents by Inventor Louis Yizhang Liu

Louis Yizhang Liu 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: 6885932
    Abstract: A method and system for a misfire detection acquires (301) a series of acceleration data (302) representative of acceleration behavior of an engine. The data is sampled (304) to obtain acceleration data samples at a rate sufficient to obtain up to fourth-order perturbations of the data. The samples are filtered (322) to provide bandwidth limited samples, which are provided to at least two channels (325, 329). The samples are pattern matched (332) in a first channel to enhance harmonic phenomena and pattern canceled (330) in a second channel to enhance random phenomena. Hard and random misfires are detected (334) dependent on a magnitude of the filtered acceleration data samples. Preferably, a third channel (335) is added to detect multiple misfires.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: April 26, 2005
    Assignee: Motorola, Inc.
    Inventors: Louis Yizhang Liu, Richard J. Gilbert, Donald P. Kultgen, Jeffrey D. Naber, Hanlong Yang
  • Patent number: 6622080
    Abstract: An electronic throttle controller (200) includes a feedforward control (222), a PID (224), a sliding mode control (226) and an adder (230). The PID (224) is capable of generating a first feedback term that compensates for an error signal. The sliding mode control (226) is capable of generating a second feedback term that incorporates a solution to a Lyapunov equation applied to the error signal with sliding gain being updated by an estimation of unknown dynamics. The adder (230) adds the first feedback term, the second feedback term and the feedforward control (222) so as to generate a control signal (232).
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: September 16, 2003
    Assignee: Motorola, Inc.
    Inventors: Hanlong Yang, Louis Yizhang Liu, Jeffrey D. Naber
  • Publication number: 20030023365
    Abstract: An electronic throttle controller (200) includes a feedforward control (222), a PID (224), a sliding mode control (226) and an adder (230). The PID (224) is capable of generating a first feedback term that compensates for an error signal. The sliding mode control (226) is capable of generating a second feedback term that incorporates a solution to a Lyapunov equation applied to the error signal with sliding gain being updated by an estimation of unknown dynamics. The adder (230) adds the first feedback term, the second feedback term and the feedforward control (222) so as to generate a control signal (232).
    Type: Application
    Filed: July 26, 2001
    Publication date: January 30, 2003
    Inventors: Hanlong Yang, Louis Yizhang Liu, Jeffrey D. Naber