Multi-Scenarios Attitude Control of a Satellite with Flexible Solar Panels

A novel partial differential equation observer is proposed to be used in boundary attitude and vibration control of flexible satellites. Solar panels’ vibrations and attitude dynamics form a coupled partial differential equation–ordinary differential equation system which is controlled directly without discretization. Few feedback signals from boundaries are required which are estimated via a partial differential equation observer. Consequently, just satellite attitude and angular velocity should be measured and still the control system benefits information from continuous part vibrations. The closed-loop system is proved to be asymptotically stable. Simulations with a finite element technique illustrate good performance of this observer-based boundary controller.

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Experimental Investigation on the Feasibility of Using a Fresnel Lens as a Solar-Energy Collection System for Enhancing On-Orbit Power Generation Performance

International Journal of Aerospace Engineering ◽

10.1155/2017/1435036 ◽

2017 ◽

Vol 2017 ◽

pp. 1-13

Author(s):

Tae-Yong Park ◽

Joo-Yong Jung ◽

Hyun-Ung Oh

Keyword(s):

Power Generation ◽

Solar Energy ◽

Attitude Control ◽

Incidence Angle ◽

Fresnel Lens ◽

Power Measurement ◽

The Sun ◽

Solar Panels ◽

Collection System ◽

Power Generation Performance

Cube satellites have a limitation for generating power because of their cubic structure and extremely small size. In addition, the incidence angle between the sun and the solar panels continuously varies owing to the revolution and rotation of the satellite according to the attitude control strategy. This angle is an important parameter for determining the power generation performance of the cube satellite. In this study, we performed an experimental feasibility study that uses a Fresnel lens as a solar-energy collection system for cube satellite applications, so that the power generation efficiency can be enhanced under the worst incidence angle condition between the sun and solar panels by concentrating and redirecting solar energy onto the solar panels with a commercial Fresnel lens. To verify the effectiveness of the proposed system, we conducted a power-measurement test using a solar simulator and Fresnel lenses at various angles to the light source. In addition, we predicted the on-orbit power-generation enhancement achieved by employing the solar-energy collection system with various attitude control strategies.

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Monitoring of a controlled space flexible multibody by means of embedded piezoelectric sensors and cameras synergy

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x18781048 ◽

2018 ◽

Vol 29 (14) ◽

pp. 2966-2978 ◽

Cited By ~ 2

Author(s):

Matteo Ribet ◽

Marco Sabatini ◽

Luca Lampani ◽

Paolo Gasbarri

Keyword(s):

Optical Sensors ◽

Attitude Control ◽

Point Of View ◽

Vibration Monitoring ◽

Structural Vibration ◽

Elastic Displacement ◽

Experimental Point ◽

Solar Panels ◽

Flexible Multibody ◽

Usual Solution

Interaction between elastic dynamics and attitude control is a serious problem in space operations, which often involve satellites with highly flexible appendages. Monitoring and eventually control of the vibrations are a major concern to avoid a decrease in the expected performance. In particular, the classic case of a central bus with two lateral appendages (solar panels) is considered. The design of a system for structural vibration monitoring is proposed both from a numerical and an experimental point of view. Piezoelectric devices are a usual solution for measuring the deformation of the structures. In the proposed work, optical sensors are also implemented: the combined use of the two sets allows for the monitoring of the elastic displacement of the solar panels and for the reconstruction of the modal shapes of the entire flexible multibody system.

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Multifunctional Structures for Attitude Control

ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems ◽

10.1115/smasis2019-5565 ◽

2019 ◽

Author(s):

Vedant ◽

James T. Allison

Keyword(s):

Attitude Control ◽

Mechanical Vibration ◽

Systems Design ◽

Small Strain ◽

Small Displacement ◽

Solar Panels ◽

Attitude Control System ◽

Deployable Structures ◽

Solar Arrays ◽

Satellite Attitude Control

Abstract The Engineering Systems Design Lab (ESDL) at the University of Illinois introduced Strain-Actuated Solar Arrays (SASAs) as a solution for precise satellite Attitude Control System (ACSs). SASA is designed to provide active mechanical vibration (jitter) cancellation, as well as small slew maneuver capabilities to hold a pose for short time periods. Current SASA implementations utilize piezoelectric distributed actuators to strain deployable structures, and the resulting momentum transfer rotates the spacecraft bus. A core disadvantage, however, is small strain and slew capability. Initial SASA systems could help improve pointing accuracy, but must be coupled with another ACS technology to produce large reorientations. A novel extension of the original SASA system is presented here that overcomes the small-displacement limitation, enabling use of SASA as a sole ACS for some missions, or in conjunction with other ACSs. This extension, known as Multifunctional Structures for Attitude Control (MSAC), can produce arbitrarily-large rotations, and has the potential to scale to large spacecraft. The system utilizes existing flexible deployable structures (such as solar arrays or radiators) as multifunctional devices. This multi-role use of solar panels extends their utility at a low mass penalty, while increasing reliability of the spacecraft ACS.

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Adaptive fuzzy Jacobian control of spacecraft combined attitude and Sun tracking system

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-02-2020-0038 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Yew-Chung Chak ◽

Renuganth Varatharajoo ◽

Nima Assadian

Keyword(s):

Attitude Control ◽

Tracking System ◽

Solar Array ◽

The Sun ◽

Solar Panels ◽

Content Type ◽

Adaptive Fuzzy ◽

Control Scheme ◽

Adaptation Law ◽

Pointing Control

Purpose The paper aims to address the combined attitude control and Sun tracking problem in a flexible spacecraft in the presence of external and internal disturbances. The attitude stabilization of a flexible satellite is generally a challenging control problem, because of the facts that satellite kinematic and dynamic equations are inherently nonlinear, the rigid–flexible coupling dynamical effect, as well as the uncertainty that arises from the effect of actuator anomalies. Design/methodology/approach To deal with these issues in the combined attitude and Sun tracking system, a novel control scheme is proposed based on the adaptive fuzzy Jacobian approach. The augmented spacecraft model is then analyzed and the Lyapunov-based backstepping method is applied to develop a nonlinear three-axis attitude pointing control law and the adaptation law. Findings Numerical results show the effectiveness of the proposed adaptive control scheme in simultaneously tracking the desired attitude and the Sun. Practical implications Reaction wheels are commonly used in many spacecraft systems for the three-axis attitude control by delivering precise torques. If a reaction wheel suffers from an irreversible mechanical breakdown, then it is likely going to interrupt the mission, or even leading to a catastrophic loss. The pitch-axis mounted solar array drive assemblies (SADAs) can be exploited to anticipate such situation to generate a differential torque. As the solar panels are rotated by the SADAs to be orientated relative to the Sun, the pitch-axis wheel control torque demand can be compensated by the differential torque. Originality/value The proposed Jacobian control scheme is inspired by the knowledge of Jacobian matrix in the trajectory tracking of robotic manipulators.

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Satellite Attitude Control System Design considering the Fuel Slosh Dynamics

Shock and Vibration ◽

10.1155/2014/260206 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 11

Author(s):

Luiz Carlos Gadelha de Souza ◽

Alain G. de Souza

Keyword(s):

Control System ◽

Attitude Control ◽

Rigid Motion ◽

Linear Quadratic Regulator ◽

Solar Panels ◽

Attitude Control System ◽

Linear Quadratic ◽

Satellite Attitude ◽

Satellite Attitude Control ◽

Fuel Slosh

The design of the satellite attitude control system (ACS) becomes more complex when the satellite structure has different type of components like, flexible solar panels, antennas, mechanical manipulators, and tanks with fuel. A crucial interaction can occur between the fuel slosh motion and the satellite rigid motion during translational and/or rotational manoeuvre since these interactions can change the satellite centre of mass position damaging the ACS pointing accuracy. Although, a well-designed controller can suppress such disturbances quickly, the controller error pointing may be limited by the minimum time necessary to suppress such disturbances thus affecting the satellite attitude acquisition. As a result, the design of the satellite controller needs to explore the limits between the conflicting requirements of performance and robustness. This paper investigates the effects of the interaction between the liquid motion (slosh) and the satellite dynamics in order to predict what the damage to the controller performance and robustness is. The fuel slosh dynamics is modelled by a pendulum which parameters are identified using the Kalman filter technique. This information is used to design the satellite controller by the linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) methods to perform a planar manoeuvre assuming thrusters are actuators.

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Sun-Pointing Attitude Control Scheme for Magnetic-based Satellite

10.21203/rs.3.rs-762718/v1 ◽

2021 ◽

Author(s):

Xiwang Xia ◽

Yonghe ZHANG ◽

Jun Jiang

Keyword(s):

Attitude Control ◽

Attitude Determination ◽

Direct Method ◽

Low Cost ◽

Solar Array ◽

Solar Panels ◽

Control Effort ◽

Control Scheme ◽

Control Schemes ◽

Magnetic Attitude Control

Abstract For some low-orbit satellites, SADA (solar array drive assembly) is not necessary but steady sun-pointing is required. Magnetic-based attitude control schemes are adopted by more and more low-cost low-orbit satellites and magnetic-based sunpointing attitude control schemes have been proposed for various satellites. For magnetic Attitude Determination and Control System (ADCS), magnetometer and magnetic torquer are the core ADCS components while sun sensor and gyro, which would be employed to determine or estimate sun vector, are important ones. Due to the underactuated characteristics, magnetic attitude control torque could not stabilize the full attitude but the two components of the attitude, simultaneously, which means that magnetic attitude control effort could orientate the solar panels to the Sun. A Lyapunov function, combining the rotational energy and sun angle, is formulated and a PD-type sun-pointing attitude control scheme is proposed to meet the requirements corresponding to sun-pointing task. Further, the effectiveness of the PD-type sun angle-based magnetic attitude control scheme, composed of proportional term, damping term and spinning term, has been verified by use of Lyapunov direct method. Simulations show that, the proposed PD-type attitude control scheme is a suitable sun-pointing scheme for magnetic satellites.

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Nonsingular Integral Sliding Mode Attitude Control for Rigid-Flexible Coupled Spacecraft with High-Inertia Rotating Appendages

Complexity ◽

10.1155/2021/8812187 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Gaowang Zhang ◽

Xueqin Chen ◽

Ruichen Xi ◽

Huayi Li

Keyword(s):

Sliding Mode Control ◽

Control Problem ◽

Attitude Control ◽

Sliding Mode ◽

Control Law ◽

Solar Panels ◽

Integral Sliding Mode ◽

Complex Control ◽

Mode Control ◽

Attitude Tracking

This study addresses the challenge of attitude tracking control for a rigid-flexible spacecraft with high-inertia rotating appendages. The Lagrange method was used to establish the kinematic and dynamic models of the spacecraft. The translation and rotation of the spacecraft, vibrations of solar panels, and imbalance caused by the rotating appendages, which cause a complex control problem, were considered. To address the complex control problem, a novel, fast nonsingular integral sliding mode control method is proposed to perform the attitude tracking function of spacecraft. A sliding mode control law was established for the high-inertia appendages to maintain an appropriate angular velocity during rotation. Finally, the effectiveness of the proposed attitude control law was verified by numerical simulations for a spacecraft with high-inertia rotating appendages and symmetrical flexible solar panels.

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Fixed-time sliding mode attitude control of a flexible spacecraft with rotating appendages connected by magnetic bearing

Mathematical Biosciences and Engineering ◽

10.3934/mbe.2022106 ◽

2022 ◽

Vol 19 (3) ◽

pp. 2286-2309

Author(s):

Gaowang Zhang ◽

◽

Feng Wang ◽

Jian Chen ◽

Huayi Li

Keyword(s):

Attitude Control ◽

Control Method ◽

Sliding Mode ◽

Fixed Time ◽

Magnetic Bearing ◽

Flexible Spacecraft ◽

Active Magnetic Bearing ◽

Connected Components ◽

Solar Panels ◽

Satellite Platform

<abstract> <p>This study focuses on the attitude control of a flexible spacecraft comprising rotating appendages, magnetic bearings, and a satellite platform capable of carrying flexible solar panels. The kinematic and dynamic models of the spacecraft were established using Lagrange methods to describe the translation and rotation of the spacecraft system and its connected components. A simplified model of the dynamics of a five-degrees-of-freedom (DOF) active magnetic bearing was developed using the equivalent stiffness and damping methods based on the magnetic gap variations in the magnetic bearing. Next, a fixed-time sliding mode control method was proposed for each component of the spacecraft to adjust the magnetic gap of the active magnetic bearing, realize a stable rotation of the flexible solar panels, obtain a high inertia for the appendage of the spacecraft, and accurately control the attitude. Finally, the numerical simulation results of the proposed fixed-time control method were compared with those of the proportional-derivative control method to demonstrate the superiority and effectiveness of the proposed control law.</p> </abstract>

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MiniCarb: A Passive, Occultation-Viewing, 6U CubeSat for Observations of CO2, CH4, and H2O

Measurement Science and Technology ◽

10.1088/1361-6501/ac3679 ◽

2021 ◽

Author(s):

Emily L Wilson ◽

Vincent J. Riot ◽

A. J. DiGregorio ◽

guruthisvaran Ramu ◽

Paul Cleveland ◽

...

Keyword(s):

Attitude Control ◽

Low Cost ◽

Lawrence Livermore National Laboratory ◽

National Laboratory ◽

Space Station ◽

Solar Panels ◽

Attitude Control System ◽

Environmental Testing ◽

Nasa Goddard Space ◽

Modular Platform

Abstract We present the final design, environmental testing, and launch history of MiniCarb, a 6U CubeSat developed through a partnership between NASA Goddard Space Flight Center and Lawrence Livermore National Laboratory. MiniCarb’s science payload, developed at Goddard, was an occultation-viewing, passive laser heterodyne radiometer for observing methane, carbon dioxide, and water vapor in Earth’s atmosphere at ~1.6 microns. MiniCarb’s satellite, developed at Livermore, implemented their CubeSat Next Generation Bus plug-and-play architecture to produce a modular platform that could be tailored to a range of science payloads. Following the launch on December 5, 2019, MiniCarb traveled to the International Space Station and was set into orbit on February 1, 2020 via Northrop Grumman’s (NG) Cygnus capsule which deployed MiniCarb with tipoff rotation of about 20 deg/sec (significantly higher than the typical rate of 3 deg/sec from prior CubeSats), from which the attitude control system was unable to recover resulting in a loss of power. In spite of this early failure, MiniCarb had many successes including rigorous environmental testing, successful deployment of its solar panels, and a successful test of the radio and communication through the Iridium network. This prior work and enticing cost (approximately $2M for the satellite and $250K for the payload) makes MiniCarb an ideal candidate for a low-cost and rapid rebuild as a single orbiter or constellation to globally observe key greenhouse gases.

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