Richard N Chiang

US Patent:

6607167, Aug 19, 2003

Filed:

Feb 1, 2001

Appl. No.:

09/775126

Inventors:

Grant Wang - Hacienda Heights CA
Richard Chiang - Rancho Palos Verdes CA

Assignee:

The Boeing Company - Chicago IL

International Classification:

B64G 144

US Classification:

244173, 244164

Abstract:

A satellite system includes a solar wing moveably connected to a satellite central body. A sensor, also coupled to the satellite central body, detects the movement of the body and generates a rate signal based on that movement. Additionally, an actuator, which controls momentum, is coupled to the satellite central body with maximum torque along the thermal shock axis. Subsequently, a rate-dominated thermal shock suppression controller, which is coupled to the satellite central body, receives the rate signal from the sensor to control the actuator.

US Patent:

6980893, Dec 27, 2005

Filed:

Nov 21, 2003

Appl. No.:

10/719628

Inventors:

Richard Y. Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G06F019/00

US Classification:

701 13, 244158 R, 375326

Abstract:

This invention introduces innovative filtering techniques to recover the instability phase margin loss due to time delay induced from a throughput shortage problem of a spacecraft central processor (SCP). This invention relates to digital control systems and, more particularly, to a phase recovery filtering technique to alleviate spacecraft central computer processor or (SCP) throughput shortages. This filtering technique recovers the unstable phase margin loss due to the time delay caused by the SCP throughput problem. The filtering techniques may be accomplished without schedule slip or extra cost to the project.

US Patent:

6988051, Jan 17, 2006

Filed:

Nov 14, 2003

Appl. No.:

10/713340

Inventors:

Richard Y. Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G06F 101/14

US Classification:

702181, 702179

Abstract:

A method of analysis to process jitter information by using a window average statistic model to determine a pointing accuracy. The pointing accuracy ultimately determines whether or not a mission can proceed. The process includes the following: collect a signal, process the signal to produce data, insert the data from the signal into a statistical model to produce statistics, compile the statistics using the statistics model to produce a probability density function, integrate the probability density function to produce a probability distribution function, determine a pointing accuracy from the probability distribution function.

US Patent:

7337021, Feb 26, 2008

Filed:

Mar 26, 2003

Appl. No.:

10/397495

Inventors:

Richard Y. Chiang - Rancho Palos Verdes CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G05B 13/02

US Classification:

700 28, 700 29, 700 30, 700 31

Abstract:

A method, apparatus, article of manufacture, and a memory structure for designing a robust controller. The method comprises the steps of determining a plant model G of the system dynamics; bounding system dynamics unmodeled by the plant model G of the system dynamics by a weighting function W; applying a transform to an augmented plant model T having the plant model G and the weighting function W; defining a controller {tilde over (F)} from the transformed plant model T; and applying an inverse of the transform to the controller {tilde over (F)} defined from the transformed plant model and the weighting function W to generate the robust controller F.

US Patent:

8131409, Mar 6, 2012

Filed:

Dec 10, 2009

Appl. No.:

12/635426

Inventors:

Tung-Ching Tsao - Torrance CA, US
Richard Y. Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G05D 1/08
B64G 1/10

US Classification:

701 13, 244164

Abstract:

A system and method for gyroless transfer orbit sun acquisition using only wing current measurement feedback is disclosed. With this system and method, a spacecraft is able to maneuver itself to orient its solar panel to its maximum solar exposure spinning attitude. The disclosed system and method involve controlling a spacecraft maneuver using only the solar wing current feedback as the sole closed-loop feedback sensor for attitude control. A spin controller is used for controlling the spacecraft spin axis orientation and spin rate. The spin controller commands the spacecraft spin axis orientation to align with an inertial fixed-direction and to rotate at a specified spin rate by using a momentum vector. In addition, a method for estimating spacecraft body angular rate and spacecraft attitude is disclosed. This method uses a combination of solar array current and spacecraft momentum as the cost function with solar wing current feedback as the only closed-loop feedback sensor.

US Patent:

8380370, Feb 19, 2013

Filed:

Jun 18, 2009

Appl. No.:

12/487187

Inventors:

Dan Y. Liu - Rancho Palos Verdes CA, US
Richard Y. Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

B64G 1/24

US Classification:

701 13, 701 3, 701 4, 701 11, 701400, 701408, 701501, 701505, 701512, 701513, 701523, 701534, 2441581, 2441584, 2441588, 244164, 244165, 244171, 2441711, 2441726

Abstract:

A system and a method for commanding a spacecraft to perform a three-axis maneuver purely based on “position” (i. e. , attitude) measurements. Using an “inertial gimbal concept”, a set of formulae are derived that can map a set of “inertial” motion to the spacecraft body frame based on position information so that the spacecraft can perform/follow according to the desired inertial position maneuvers commands. Also, the system and method disclosed herein employ an intrusion steering law to protect the spacecraft from acquisition failure when a long sensor intrusion occurs.

US Patent:

8620496, Dec 31, 2013

Filed:

Jul 23, 2008

Appl. No.:

12/178440

Inventors:

Dan Y. Liu - Rancho Palos Verdes CA, US
Qinghong W. Wang - Torrance CA, US
Richard Y. Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

B64G 1/38
B64G 1/28

US Classification:

701 13, 244165, 244170

Abstract:

A system for damping nutation and removing wobble of a spacecraft spinning about a given axis is provided. The system includes a sensor configured to determine three dimensional attitude measurements of the spacecraft, a processor operatively coupled to the sensor and configured to execute a process that facilitates aligning the spin axis with a spacecraft momentum vector. The processor, when executing the process, is programmed to receive spacecraft attitude data from the sensor, determine a torque command using the received attitude data, and control a momentum storage actuator on the spacecraft using the determined torque command such that an angular deviation about the given axis is reduced.

US Patent:

20050131592, Jun 16, 2005

Filed:

Dec 15, 2003

Appl. No.:

10/737588

Inventors:

Richard Chiang - Torrance CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G06F007/00

US Classification:

701013000

Abstract:

A method for in-flight stability margin assessment includes steps of: exciting a control system with a wide band spectrum excitation signal to produce in-flight data; storing the in-flight data in an on-board computer during operation of a spacecraft mission; downloading the in-flight data via telemetry during operation of the spacecraft mission; estimating a system sensitivity function by taking the ratio of an output power spectrum to an input power spectrum; and determining stability margins of the attitude control system from the system sensitivity function by determining a gain margin GM and a phase margin PM from the formulas: where “a” is the reciprocal of the peak of the system sensitivity function. The method optionally includes redesigning and providing a new control law to the control system if deemed necessary.