A5004914787- Magnetic Bearings and Levitation Dynamics
- Inertial Sensor and Navigation
- Geomagnetism and Paleomagnetism Studies
- Tribology and Lubrication Engineering
- Magnetic and Electromagnetic Effects
- Electric Motor Design and Analysis
- Magnetic Field Sensors Techniques
- Micro and Nano Robotics
- Space Satellite Systems and Control
- Spacecraft Design and Technology
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Modular Robots and Swarm Intelligence
- Characterization and Applications of Magnetic Nanoparticles
- Photoacoustic and Ultrasonic Imaging
- Solar Radiation and Photovoltaics
- Sparse and Compressive Sensing Techniques
- Electrical Contact Performance and Analysis
- Adaptive optics and wavefront sensing
- Radiation Effects in Electronics
- Advanced Measurement and Metrology Techniques
- GNSS positioning and interference
- Astronomical Observations and Instrumentation
- Underwater Vehicles and Communication Systems
- Healthcare Technology and Patient Monitoring
Swiss Center for Electronics and Microtechnology (Switzerland)
2010-2021
Istituto Ricerche Solari Locarno
2010
Università della Svizzera italiana
2010
This paper presents an analytical model for the force and torque developed by a reaction sphere actuator satellite attitude control. The is innovative momentum exchange device consisting of magnetic bearings spherical rotor that can be electronically accelerated in any direction making all three axes stabilized spacecrafts controllable unique device. composed 8-pole permanent magnet 20-coil stator. Force models are derived solving Laplace equation applying Lorentz law. novelty consists...
This paper presents the rotor design optimization for a reaction sphere (RS) actuator. The RS is permanent-magnet synchronous spherical actuator whose magnetically levitated and can be accelerated about any desired axis. composed of an 8-pole (PM) 20-coil stator. Due to highly complex geometry rotor, consisting eight bulk PM poles with truncated shape adjusted on back-iron structure octahedral shape, pure analytical approach problem not practicable. Therefore, given set specifications,...
Magnetic bearings represent an important alternative to conventional ball for applications that require very low noise and vibrations. The absence of contact friction between rotor stator parts, combined with the use active vibration control techniques, result in rotating machinery can greatly outperform their passive counterparts. One main disadvantages these systems is increased complexity requiring rotor, including sensors actuators computing power. Furthermore, techniques are generally...
A recently proposed technique to control the satellite attitude using a magnetically levitated sphere requires development of suitable models its dynamics. One phenomena that can affect motion system are eddy currents induced in stator actuator due time variable magnetic field generated by rotational permanent magnet rotor. We present an analytical model for with eight-pole The is derived second-order vector potential-based approach, and solution obtained terms spherical harmonic functions....
Efficiency is one of the key performance indexes in design electric motors. When considering fully active magnetic bearing machines, this aspect gains further relevance due to necessity actively controlling all remaining degrees freedom rotor addition its rotation. This article presents a strategy for efficiency maximization rotating machinery featuring slotless bearings and motor. The optimization maximizes motor constants, allowing combined minimization losses generated forces torques. Due...
This paper presents the development of an analytical model for force and torque developed by a Reaction Sphere satellite attitude control. The is magnetic bearings spherical motor whose rotation axis can be electronically controlled. actuator composed 8-pole permanent magnet rotor 20-pole stator. Force models are derived solving Laplace equation applying Lorentz law. Using linear superposition principle, expression formulated in matrix form. validated through open loop measurement campaign...
This paper presents an open-loop strategy for the control of orientation a reaction sphere actuator. The is magnetic bearing spherical motor composed 8-pole permanent magnet rotor and 20-pole stator. law based on rotating field obtained from sequence desired orientations. Hence, can be accelerated about any axis. Force torque inverse models are developed employed to derive scheme. proposed method successfully drive laboratory prototype up 480 rpm.
This paper presents a hybrid FEM-analytical model for the magnetic flux density, force and torque of Reaction Sphere (RS) actuator satellite attitude control. The RS is permanent magnet synchronous spherical whose rotor magnetically levitated can be accelerated about any desired axis. composed an 8-pole 20-coil stator. Due to highly complex geometry rotor, consisting 8 bulk poles with truncated shape adjusted on back-iron structure octahedral shape, pure analytical approach not possible....
This paper presents a procedure to estimate the back-EMF voltages and rotor angular velocity of reaction sphere actuator for satellite attitude control. The is permanent magnet synchronous spherical whose magnetically levitated can be accelerated about any desired axis. composed an 8-pole 20-coil stator. developed technique measure based on Faraday's law, in which magnetic flux density decomposed harmonic basis, expansion parameters are derived from measurements radial component field...
This paper describes the necessary steps and mitigation techniques to minimize magnetic field of a reaction wheel. Stringent emission requirements resulted in design an active compensation system counteract changing wheel field. The motor emissions are measured for different operational modes modelled according these measurements. opposite is then applied compensation. will discuss feasibility challenges approach as well other strategies employed design. Findings from Breadboard tests be...
Keywords: satellite attitude control ; reaction sphere spherical actuator electromagnetic modeling magnetic flux density model harmonics force and torque state bearing design optimization These Ecole polytechnique federale de Lausanne EPFL, n° 6311 (2010)Programme doctoral Systemes production et RobotiqueFaculte des sciences techniques l'ingenieurInstitut microtechniqueLaboratoire d'actionneurs integresJury: Prof. F. Mondada (president) Y. Perriard (directeur) H. Bleuler, Dr O. Chetelat, B....
This paper presents a novel angular velocity estimation strategy of Reaction Sphere (RS) for satellite attitude control based on Linear Parameter-Varying (LPV) Kalman Filter. The reaction sphere is permanent magnet synchronous spherical actuator whose rotor magnetically levitated and can be accelerated about any desired axis. composed an 8-pole 20-coil stator. proposed technique relies the implementation Filter observer over LPV state-space model dynamics harmonic decomposition magnetic flux...
This article presents the analysis of three-dimensional forces applied by a slotless Lorentz-type fully-active magnetic bearing actuator. An analytical model is presented for defining every radial and axial actuator, which allows identifying cross-couplings deviations from ideal forces, an essential step their minimisation. A validation campaign performed to guarantee assess accuracy such employing demonstrator that features dual hetero/hompolar machine design.
The most common technique for satellite attitude control assumes the use of rotating mechanical parts on-board. Traditionally such a system consists one to four Reaction Wheels or Control Moment Gyroscopes. orientation can be done by acceleration proper wheel around its axis rotation. changes according conservation angular momentum law if appropriate appears. As potential alternative set Wheels, single Sphere held in position magnetic levitation has been proposed. Authors this paper are...
This article presents an optimization strategy to position magnetic flux density sensors in a reaction sphere actuator. The consists bearings spherical rotor whose rotation axis can be electronically controlled. actuator is composed of 8-pole permanent magnet and 20-coil stator. Force torque analytical models the are parameterized using 7 decomposition coefficients that deliver all necessary information relative orientation inside These determined non-iteratively linear fashion by measuring...
This article presents the development and validation of a three-dimensional force torque semi-analytical model for ironless permanent magnet structures. method relies on definition magnetic flux density generated by magnets in terms elliptic integrals, allowing fast computation when compared with finite element methods (FEM). The approach is validated shown two passive bearing configurations studying applied force, stiffness small displacements tilting are present.
Due to a growing interest for imagery with high spatial and spectral resolution, Earth Observation sensors are producing increasing amounts of data. This poses severe challenge in terms computational, memory transmission requirements. In order overcome these limitations, fascinating approach is the implementation compressive sensing architecture. this paper, we present an instrumental concept based on use light modulator implement super-resolved, demonstrator instrument aimed at visible...