Design-filter selection for H2 control of microgravity isolation systems - A single-degree-of-freedom case study

AIAA Guidance, Navigation, and Control Conference and Exhibit

2002

The acceleration environment on the Intern ational Space Station (ISS) will likely exceed the requirements of many micro-gravity experiments. The Glovebox Integrated Microgravity Isolation Technology (g-LIMIT) is being built by the NASA Marshall Space Flight Center to attenuate the nominal acceleration environment and provide some isolation for microgravity science experiments. G-LIMIT uses Lorentz (voice-coil) magnetic actuators to isolate a platform for mounting science payloads from the nominal acceleration environment. The system utilizes payload acceleration, relative position, and relative orientation measurements in a feedback controller to accomplish the vibration isolation task. The controller provides current commands to six magnetic actuators, producing the required experiment isolation from the ISS acceleration environment. This paper presents the development of a candidate control law to meet the acceleration attenuation requirements for the g-LIMIT experiment platform. The controller design is developed using linear optimal control techniques for frequency-weighted H 2 norms. Comparison of the performance and robustness to plant uncertainty for this control design approach is included in the discussion.

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Section: Introductionmentioning

confidence: 99%

Optimal Control Design Using an H2 Method for the Glovebox Integrated Microgravity Isolation Technology (g-LIMIT)

AIAA Guidance, Navigation, and Control Conference and Exhibit

2002

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“…Any controller using only acceleration feedback to attenuate indirect disturbances will also automatically result in attenuation of direct disturbances (ref. 4). This attenuation stems from the increase in effective mass due to an acceleration-only feedback controller.…”

Section: Candidate H 2 Control Designmentioning

confidence: 99%

“…4). Recent research demonstrated the usefulness of this method for designing SDOF controllers to meet the vibration isolation criteria (ref.…”

Section: Candidate H 2 Control Designmentioning

confidence: 99%

“…The above design criteria should be met while limiting the actuator control effort to less than 40 amps/micro-g over the entire frequency range (ref. 4). …”

Section: Candidate H 2 Control Designmentioning

confidence: 99%

“…Recent research demonstrated the usefulness of this method for designing SDOF controllers to meet the vibration isolation criteria (ref. 4). The method was subsequently applied for the design of controllers for multi-input multi-output (MIMO), multi-degree-of-freedom (MDOF) systems (ref.…”

Section: Candidate H 2 Control Designmentioning

confidence: 99%

See 2 more Smart Citations

Frequency Weighted H2 Control Design for the Glovebox Integrated Microgravity Isolation Technology (g-limit)

AIAA Guidance, Navigation, and Control Conference and Exhibit

2003

Glovebox Integrated Microgravity Isolation Technology (g-LIMIT): A Linearized State-Space Model

42nd AIAA Aerospace Sciences Meeting and Exhibit

Whorton

2004