The Experts below are selected from a list of 2592 Experts worldwide ranked by ideXlab platform
Chee Khiang Pang - One of the best experts on this subject based on the ideXlab platform.
-
robust concurrent attitude position control of a swarm of underactuated Nanosatellites
IEEE Transactions on Control Systems and Technology, 2018Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we address the formation flying problem of underactuated Nanosatellites by concurrent attitude-position control. Lack of space in Nanosatellites hinders us from having omnidirectional motion capabilities. Hence, a practical model for Nanosatellites is to employ a one-directional propulsion system together with the reaction wheels. To achieve the formation flying of such Nanosatellites, we develop a strategy based on the simultaneous control of attitude and position. The proposed formation flying method consists of three sublevels: first for each underactuated nanosatellite, a virtual fully actuated system is considered and a finite-time translational control method together with a disturbance estimator is developed for the fully actuated system. Subsequently, an adaptive finite-time attitude tracking is proposed to align the thruster of each underactuated nanosatellite with the obtained translational input of the corresponding virtual fully actuated system. Finally, by using the attitude and the obtained virtual input, the thrust for each underactuated nanosatellite is computed. Unlike the existing methods that are merely limited to control of fully actuated satellites, the proposed method presents a robust concurrent formation flying control for a group of underactuated Nanosatellites, and accounts for disturbances such as air drag. A rigorous mathematical formulation and the stability analysis of the system are provided. Simulation results are presented to illustrate the performance of the proposed method.
-
Energy-efficient control of Nanosatellites during distributed region formation flying
Control Theory and Technology, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we present an energy-efficient method for distributed region formation flying of Nanosatellites. The proposed framework consists of two concurrent sub-schemes that include estimation and formation. In the estimation sub-scheme, unlike the existing methods on satellite formation flying, that assume the availability of the reference orbital elements to all followers, here, a distributed estimator is developed so that the follower Nanosatellites estimate the position of the leader in its orbital slot. In the formation sub-scheme, we consider a region formation strategy which is an efficient method in dealing with the formation of a large number of Nanosatellites. We propose an optimal region following formation method based on the receding horizon control (RHC) using the estimated reference orbital elements. Subsequently, an algorithm is presented to solve the proposed energy-efficient formation flying method. Finally, the simulation result is presented that illustrates the purposed method improves the power consumption for each nanosatellite with respect to the existing non-optimal region formation flying controllers.
-
concurrent attitude position control of under actuated Nanosatellites for formation flying
International Conference on Control and Automation, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:This paper presents formation flying for under-actuated Nanosatellites based on concurrent attitude-position control. Compared to existing methods that rely on independent rotational and translational control, here because of under-actuated inherent attribute of the problem a triple-tiered approach based on concurrent attitude-position control is developed. The proposed approach consists of following sub-control layers: at first a virtual fully-actuated model of Nanosatellites based on relative motion is introduced. Consequently, an adaptive finite-time attitude control is proposed to align Nanosatellites towards obtained virtual translational inputs. Finally, using the virtual translational inputs and attitude of nanosatelites, the desired thrusts are computed. The proposed idea shed light on future Nanosatellites formation flying missions. Simulation results are presented to illustrate the applicability of the proposed method in Nanosatellites.
-
distributed optimal formation flying control of a group of Nanosatellites
International Conference on Control and Automation, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we present an energy-efficient method for distributed formation flying of Nanosatellites. The proposed framework consists of two concurrent sub-schemes include estimation and formation. Unlike existing methods on satellite formation flying, that assume the availability of reference orbital elements to all followers, here, a distributed estimator is developed so that follower Nanosatellites estimate the position of leader in its orbital slot. Using the estimated position of leader nanosatellite, an optimal region following formation method based on Receding Horizon Control (RHC) is proposed. Simulation results are presented to illustrate the performance of the proposed methodology.
Reza Haghighi - One of the best experts on this subject based on the ideXlab platform.
-
robust concurrent attitude position control of a swarm of underactuated Nanosatellites
IEEE Transactions on Control Systems and Technology, 2018Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we address the formation flying problem of underactuated Nanosatellites by concurrent attitude-position control. Lack of space in Nanosatellites hinders us from having omnidirectional motion capabilities. Hence, a practical model for Nanosatellites is to employ a one-directional propulsion system together with the reaction wheels. To achieve the formation flying of such Nanosatellites, we develop a strategy based on the simultaneous control of attitude and position. The proposed formation flying method consists of three sublevels: first for each underactuated nanosatellite, a virtual fully actuated system is considered and a finite-time translational control method together with a disturbance estimator is developed for the fully actuated system. Subsequently, an adaptive finite-time attitude tracking is proposed to align the thruster of each underactuated nanosatellite with the obtained translational input of the corresponding virtual fully actuated system. Finally, by using the attitude and the obtained virtual input, the thrust for each underactuated nanosatellite is computed. Unlike the existing methods that are merely limited to control of fully actuated satellites, the proposed method presents a robust concurrent formation flying control for a group of underactuated Nanosatellites, and accounts for disturbances such as air drag. A rigorous mathematical formulation and the stability analysis of the system are provided. Simulation results are presented to illustrate the performance of the proposed method.
-
Energy-efficient control of Nanosatellites during distributed region formation flying
Control Theory and Technology, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we present an energy-efficient method for distributed region formation flying of Nanosatellites. The proposed framework consists of two concurrent sub-schemes that include estimation and formation. In the estimation sub-scheme, unlike the existing methods on satellite formation flying, that assume the availability of the reference orbital elements to all followers, here, a distributed estimator is developed so that the follower Nanosatellites estimate the position of the leader in its orbital slot. In the formation sub-scheme, we consider a region formation strategy which is an efficient method in dealing with the formation of a large number of Nanosatellites. We propose an optimal region following formation method based on the receding horizon control (RHC) using the estimated reference orbital elements. Subsequently, an algorithm is presented to solve the proposed energy-efficient formation flying method. Finally, the simulation result is presented that illustrates the purposed method improves the power consumption for each nanosatellite with respect to the existing non-optimal region formation flying controllers.
-
concurrent attitude position control of under actuated Nanosatellites for formation flying
International Conference on Control and Automation, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:This paper presents formation flying for under-actuated Nanosatellites based on concurrent attitude-position control. Compared to existing methods that rely on independent rotational and translational control, here because of under-actuated inherent attribute of the problem a triple-tiered approach based on concurrent attitude-position control is developed. The proposed approach consists of following sub-control layers: at first a virtual fully-actuated model of Nanosatellites based on relative motion is introduced. Consequently, an adaptive finite-time attitude control is proposed to align Nanosatellites towards obtained virtual translational inputs. Finally, using the virtual translational inputs and attitude of nanosatelites, the desired thrusts are computed. The proposed idea shed light on future Nanosatellites formation flying missions. Simulation results are presented to illustrate the applicability of the proposed method in Nanosatellites.
-
distributed optimal formation flying control of a group of Nanosatellites
International Conference on Control and Automation, 2016Co-Authors: Reza Haghighi, Chee Khiang PangAbstract:In this paper, we present an energy-efficient method for distributed formation flying of Nanosatellites. The proposed framework consists of two concurrent sub-schemes include estimation and formation. Unlike existing methods on satellite formation flying, that assume the availability of reference orbital elements to all followers, here, a distributed estimator is developed so that follower Nanosatellites estimate the position of leader in its orbital slot. Using the estimated position of leader nanosatellite, an optimal region following formation method based on Receding Horizon Control (RHC) is proposed. Simulation results are presented to illustrate the performance of the proposed methodology.
Leonardo M. Reyneri - One of the best experts on this subject based on the ideXlab platform.
-
design and analysis of a rectangular pcb printed magnetorquer for Nanosatellites
IEEE Journal on Miniaturization for Air and Space Systems, 2021Co-Authors: Hassan Ali, Muhammad Rizwan Mughal, Qamar Ul Islam, Rehan Mahmood, M R Anjum, Leonardo M. ReyneriAbstract:CubeSats have become increasingly important in the last two decades and are playing a very important role in the space industry, especially with Earth-oriented Nanosatellites. Earth-oriented Nanosatellites require more precise attitude control when there is a requirement for good pointing accuracy. In such missions, passive control systems are not suitable due to their low accuracy, hence, active control systems are used. Different types of actuators are available, but magnetic actuators are best suited for low-Earth orbit (LEO) Nanosatellites. When current moves through the wire, a magnetic field is generated which is used to generate torque. The torque generated makes it possible to control the attitude of the satellite in the desired direction. The best option for Nanosatellites is to use the printed or embedded magnetorquers due to its scalable, reconfigurable, and modular approach. Printing the magnetorquer into the internal layers of the printed circuit board (PCB) reduce the harness complexities and space constraints effectively. The optimized design of the printed magnetorquer is selected by analyzing various parameters, such as turn width, distance between two turns, applied voltage, external dimensions, and internal dimensions. The design also takes into consideration other parameters, such as generated torque, torque-to-power ratio, magnetic field to current ratio, consumed power, rotation time, and thermal analysis, by changing the optimizing variables and taking into account the most important key design drivers. The design selection and results of the analysis concerning the selection of optimized parameters are presented.
-
Optimized Design and Thermal Analysis of Printed Magnetorquer for Attitude Control of Reconfigurable Nanosatellites
IEEE Transactions on Aerospace and Electronic Systems, 2020Co-Authors: Muhammad Rizwan Mughal, Jaan Praks, Leonardo M. ReyneriAbstract:An attitude control system (ACS) is one of the critical subsystems of any spacecraft and typically is in charge of de-tumbling, controlling, and orienting the satellite after initial deployment and during the satellite operations. The magnetorquer is a core magnetic attitude control actuator and, therefore, a good choice for nanosatellite attitude stabilization. There are various methods to achieve control torque using the magnetorquer. An innovative design of a printed magnetorquer has been proposed for the Nanosatellites, which is modular, scalable, cost effective, less prone to failure, with reduce harness and power consumption since the traces are printed either on the top layer or inner layers of the printed circuit board. The analysis in terms of generated torque with a range of input applied voltages, trace widths, outer and inner-most trace lengths is presented to achieve the optimized design. The optimum operating voltage is selected to generate the desired torque while optimizing the torque to the power ratio. The results of the analysis in terms of the selection of optimized parameters, including torque to power ratio, generated magnetic dipole moment, and power consumption, have been validated practically on a CubeSat panel. The printed magnetorquer configuration is modular which is useful to achieve mission level stabilization requirements. For spin-stabilized satellites, the rotation time analysis has been performed using the printed magnetorquer.
-
design implementation and thermal modeling of embedded reconfigurable magnetorquer system for Nanosatellites
IEEE Transactions on Aerospace and Electronic Systems, 2015Co-Authors: Anwar Ali, Leonardo M. Reyneri, Rizwan M Mughal, Haider Ali, Naveed M AmanAbstract:A reconfigurable magnetorquer coil has been designed and implemented for the CubeSat power management, attitude determination, and control tile (CubePMT) module of CubeSat-standard Nanosatellites. Magnetorquer coil is a good choice for attitude control and stabilization of Nanosatellites. The goal of this work is to provide CubeSat with a magnetorquer coil, which has small dimensions, low weight, and low heat dissipation. The designed magnetorquer coil is reconfigurable and integrated within the printed circuit board internal layers, occupying no extra space on CubeSat. Coils in each layer are treated separately and can be attached and detached through straps. Changing the arrangement of these straps, one can use 1, 2, 3, or 4 coils in series, parallel, or any hybrid combination. This reconfigurable design provides an option for generating different amounts of magnetic moment and resultant torque to stabilize and rotate the satellite. Emissivity of the CubePMT module was found through lab experiments. Power dissipation and the corresponding temperature increase of the CubePMT module are evaluated by thermal modeling.
Muhammad Rizwan Mughal - One of the best experts on this subject based on the ideXlab platform.
-
design and analysis of a rectangular pcb printed magnetorquer for Nanosatellites
IEEE Journal on Miniaturization for Air and Space Systems, 2021Co-Authors: Hassan Ali, Muhammad Rizwan Mughal, Qamar Ul Islam, Rehan Mahmood, M R Anjum, Leonardo M. ReyneriAbstract:CubeSats have become increasingly important in the last two decades and are playing a very important role in the space industry, especially with Earth-oriented Nanosatellites. Earth-oriented Nanosatellites require more precise attitude control when there is a requirement for good pointing accuracy. In such missions, passive control systems are not suitable due to their low accuracy, hence, active control systems are used. Different types of actuators are available, but magnetic actuators are best suited for low-Earth orbit (LEO) Nanosatellites. When current moves through the wire, a magnetic field is generated which is used to generate torque. The torque generated makes it possible to control the attitude of the satellite in the desired direction. The best option for Nanosatellites is to use the printed or embedded magnetorquers due to its scalable, reconfigurable, and modular approach. Printing the magnetorquer into the internal layers of the printed circuit board (PCB) reduce the harness complexities and space constraints effectively. The optimized design of the printed magnetorquer is selected by analyzing various parameters, such as turn width, distance between two turns, applied voltage, external dimensions, and internal dimensions. The design also takes into consideration other parameters, such as generated torque, torque-to-power ratio, magnetic field to current ratio, consumed power, rotation time, and thermal analysis, by changing the optimizing variables and taking into account the most important key design drivers. The design selection and results of the analysis concerning the selection of optimized parameters are presented.
-
Optimized Design and Thermal Analysis of Printed Magnetorquer for Attitude Control of Reconfigurable Nanosatellites
IEEE Transactions on Aerospace and Electronic Systems, 2020Co-Authors: Muhammad Rizwan Mughal, Jaan Praks, Leonardo M. ReyneriAbstract:An attitude control system (ACS) is one of the critical subsystems of any spacecraft and typically is in charge of de-tumbling, controlling, and orienting the satellite after initial deployment and during the satellite operations. The magnetorquer is a core magnetic attitude control actuator and, therefore, a good choice for nanosatellite attitude stabilization. There are various methods to achieve control torque using the magnetorquer. An innovative design of a printed magnetorquer has been proposed for the Nanosatellites, which is modular, scalable, cost effective, less prone to failure, with reduce harness and power consumption since the traces are printed either on the top layer or inner layers of the printed circuit board. The analysis in terms of generated torque with a range of input applied voltages, trace widths, outer and inner-most trace lengths is presented to achieve the optimized design. The optimum operating voltage is selected to generate the desired torque while optimizing the torque to the power ratio. The results of the analysis in terms of the selection of optimized parameters, including torque to power ratio, generated magnetic dipole moment, and power consumption, have been validated practically on a CubeSat panel. The printed magnetorquer configuration is modular which is useful to achieve mission level stabilization requirements. For spin-stabilized satellites, the rotation time analysis has been performed using the printed magnetorquer.
Serra, Paul C. - One of the best experts on this subject based on the ideXlab platform.
-
The Miniature Optical Communication Transceiver—A Compact, Power-Efficient Lasercom System for Deep Space Nanosatellites
'MDPI AG', 2019Co-Authors: Barnwell Nathan, Ritz Tyler, Parry Samantha, Clark Myles, Conklin, John W., Serra, Paul C.Abstract:Optical communication is becoming more prevalent in orbit due to the need for increased data throughput. Nanosatellites, which are satellites that typically weigh less than 10 kg, are also becoming more common due to lower launch costs that enable the rapid testing of technology in a space environment. Nanosatellites are cheaper to launch than their larger counterparts and may be a viable option for communicating beyond Earth’s orbit, but have strict Size, Weight, and Power (SWaP) requirements. The Miniature Optical Communication Transceiver (MOCT) is a compact optical transceiver designed to provide modest data rates to SWaP constrained platforms, like Nanosatellites. This paper will cover the optical amplifier characterization and simulated performance of the MOCT amplifier design that produces 1 kW peak power pulses and closes three optical links which include Low Earth Orbit (LEO) to Earth, LEO to LEO, and Moon to Earth. Additionally, a benchtop version of the amplifier design was constructed and was able to produce amplified pulses with 1.37 W peak power, including a 35.7% transmit optics loss, at a pump power of 500 mW. Finally, the modulator, seed laser, amplifier, receiver, and time-to-digital converter were all used together to measure the Bit Error Ratio (BER), which was 0.00257 for a received optical peak power of 176 nW. Keywords: optical communication; laser; nanosatellite; CubeSat; EDFA; transceiver; PPM; BERUnited States. National Aeronautics and Space Administration (Grant NNX14AO53G
