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Tung Aiying Liu

from Azusa, CA
Age ~64
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Also known as:
Tung A Liu, Tung Ai Liu, Tung Yu Liu, Tung Wu Liu, Tung Ai Ying Liu, Tung Ai-Ying Liu, Tung Y Liu, Amy A Liu, Ai Ying Liu Tung, Ronnie Liu
Related to:
George C Tung, 46
Connected to:
Abby Liu, 36Alba Liu, 47Alina Y Liu, 52Annan R Liu, 52Antong Liu, 34Anwei Liu, 61Bai Liu, 65Bao Liu, 50Baoxian Liu, 54Bella C Liu, 100

Tung Liu Phones & Addresses

  • Azusa, CA
  • Milpitas, CA
  • San Jose, CA
  • Butte Valley, CA
  • Black Point, CA
  • Roosevelt Corner, CA
  • Azusa, CA
  • Fremont, CA
  • 1093 Huntingdon Dr, San Jose, CA 95129

Work

Position: Machine Operators, Assemblers, and Inspectors Occupations

Education

Degree: High school graduate or higher

Resumes

Resumes

Tung Liu Photo 1

Tung Liu

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Tung Liu Photo 2

Student At University Of California, Los Angeles

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Location:
Greater Los Angeles Area
Industry:
Accounting

Business Records

Name / Title
Company / Classification
Phones & Addresses
Tung Yu Liu
President
Golden Liu, Inc
Business Services at Non-Commercial Site
712 High Gln Dr, San Jose, CA 95133
Tung Yuan Liu
President
WITTY CORPORATION

Publications

Us Patents

Solar Array Stepping To Minimize Array Excitation

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US Patent:
48432946, Jun 27, 1989
Filed:
Dec 1, 1987
Appl. No.:
7/127344
Inventors:
Mahabaleshwar K. P. Bhat - San Jose CA
Tung Y. Liu - Union City CA
Carl T. Plescia - Sunnyvale CA
Assignee:
Ford Aerospace & Communications Corporation - Detroit MI
International Classification:
H02P 800
US Classification:
318696
Abstract:
Mechanical oscillations of a mechanism containing a stepper motor, such as a solar-array powered spacecraft, are reduced and minimized by the execution of step movements in pairs of steps, the period between steps being equal to one-half of the period of torsional oscillation of the mechanism. Each pair of steps is repeated at needed intervals to maintain desired continuous movement of the portion of elements to be moved, such as the solar array of a spacecraft. In order to account for uncertainty as well as slow change in the period of torsional oscillation, a command unit may be provided for varying the interval between steps in a pair.

Compensated Transition For Spacecraft Attitude Control

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US Patent:
52220230, Jun 22, 1993
Filed:
Apr 2, 1991
Appl. No.:
7/679655
Inventors:
Tung Y. Liu - Union City CA
Scott W. Tilley - Belmont CA
Assignee:
Space Systems/Loral, Inc. - Palo Alto CA
International Classification:
B64G 138
US Classification:
364434
Abstract:
An improved method for transitioning a spacecraft from a thruster (5) controlled, station keeping mode to an operational, on-orbit mode, in which attitude control is maintained using internal momentum wheels (3). The method first utilizes a thruster compensation technique to supplement the conventional transition mode control system. This compensation uses empirical thruster data to derate thruster (5) efficiency for extremely short pulse durations necessarily used in transition mode operation. Secondly, a three step deadbeat thruster (5) sequence is employed in which a first pulse linearizes spacecraft (1) motion prior to orienting and stopping nutation. This linearization provides improved accuracy in computing and shortens the waiting time for subsequent thruster (5) firings.

Spacecraft Attitude Control And Momentum Unloading Using Gimballed And Throttled Thrusters

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US Patent:
53495322, Sep 20, 1994
Filed:
Apr 28, 1992
Appl. No.:
7/875276
Inventors:
Scott W. Tilley - Belmont CA
Tung Y. Liu - Union City CA
John S. Higham - Mountain View CA
Assignee:
Space Systems/Loral - Palo Alto CA
International Classification:
B64G 126
B64G 124
F03H 100
US Classification:
364459
Abstract:
A spacecraft (201) maintains its north-south positioning by using one of two pairs of single-gimballed throttled thrusters (221-224) on a face of the spacecraft (201). The throttles (118) and gimbals (116) of the thrusters (221-224) are controlled to produce torques on the spacecraft (201) that will maintain a desired attitude for the spacecraft (201) while simultaneously desaturating the momentum stabilizing wheels ( 120, 121 ) of the spacecraft (201).

Control System And Method For Spacecraft Attitude Control

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US Patent:
54596696, Oct 17, 1995
Filed:
Feb 14, 1994
Appl. No.:
8/195393
Inventors:
Rhys Adsit - Milpitas CA
Tung Liu - Union City CA
Fred N. T. Chan - Atherton CA
Charles J. Weyandt - Yardley PA
Scott Tilley - Belmont CA
Assignee:
Space Systems/Loral, Inc. - Palo Alto CA
International Classification:
B64G 110
US Classification:
364459
Abstract:
Position control methods are described for satellites and spacecraft for controlling transition from thruster control to momentum wheel control in a three-axis stabilized spacecraft. Transition from a high-bandwidth, high-torque thruster-controlled stationkeeping (SK) mode to a low bandwidth, low torque momentum wheel On-Orbit Mode is carried out. Usually a unique threshold entry method to automatically initiate the transition mode at the point with the most favorable dynamics. Also, the disclosed method eliminates the use of nutation in conjunction with a deadbeat thruster sequence to correct the spacecraft attitude to improve pointing performance and significantly shorten the time spent in the transition mode.

Method Using Double Thruster Firings To Deadbeat Flexible Solar Array Structural Oscillations

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US Patent:
59574119, Sep 28, 1999
Filed:
Dec 24, 1997
Appl. No.:
8/998173
Inventors:
Tung Y Liu - Union City CA
Kam K Chan - San Jose CA
Assignee:
Space Systems/Loral, Inc. - Palo Alto CA
International Classification:
B64G 126
US Classification:
244169
Abstract:
A spacecraft includes a plurality of thrusters mounted at predetermined locations on a spacecraft structure, individual ones the plurality of thrusters being fired for generating a torque about a desired axis. The firing of a thruster is partitioned into two firings that are offset in time by an amount. DELTA. t, wherein. DELTA. t=(1/2). times. (1/F). times. SF, where F is a dominant modal frequency, in Hertz, for any particular axis (nominally the 1st mode) of the spacecraft structure, and where SF is a scale factor that is adjustable about the frequency. In a presently preferred embodiment the thruster is a low thrust thruster that is mounted on a solar array panel, and the thrusters are fired in pairs.

Spacecraft And Appendage Stepping Methods That Improve Spacecraft Attitude Pointing And Cancel Solar Array Slew Disturbances

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US Patent:
63119293, Nov 6, 2001
Filed:
Nov 26, 1999
Appl. No.:
9/449404
Inventors:
Fatima Kazimi - Santa Cruz CA
Keith Reckdahl - Palo Alto CA
Tung Liu - Union City CA
Yat Fai Leung - Redwood City CA
John Higham - Mountain View CA
Assignee:
Space Systems/Loral, Inc. - Palo Alto CA
International Classification:
B64G 100
B64G 124
US Classification:
244158R
Abstract:
A spacecraft having a body, one or more appendages coupled thereto, and a controller that implements methods that rotate the one or more flexible appendages to point it (them) towards the Sun to reduce spacecraft attitude pointing disturbances and improves spacecraft attitude pointing. The steps of the one or more appendages are timed to deadbeat the disturbance imparted to the spacecraft body. Timing of the appendage steps may be such that the periodic disturbances are phased to substantially cancel each other, or phased to decrease the magnitude of the net disturbance. The present invention also cancels solar array slew disturbances. The present invention cancels predictable disturbance torques before they produce a pointing error, improving the spacecraft pointing performance. The present invention predicts a disturbance torque exerted on the body due to the controller moving the one or more appendages, calculates a feedforward torque necessary for the controller to cancel the disturbance torque and includes the feedforward torque in the calculation of the total control torque applied to the body.
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Tung Aiying Liu from Azusa, CA, age ~64 Get Report