Space subsystems design: (navigation, control, structure and…)
Ehsan Maani; Peyman Nikpey; Ehsan Zabihian
Volume 14, Issue 1 , March 2021, , Pages 23-33
Abstract
n GEO communicational satellites, thrusts are being used for many missions such as station keeping, longitude change maneuver and actuators desaturation. These types of actuators need fuel and its estimation requires many complicated calculations. In this paper, a novel method based on availed data for ...
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n GEO communicational satellites, thrusts are being used for many missions such as station keeping, longitude change maneuver and actuators desaturation. These types of actuators need fuel and its estimation requires many complicated calculations. In this paper, a novel method based on availed data for previous satellites is proposed for estimation of satellite fuel mass and it does not need mathematical modeling of satellite dynamics. Two methods, least square method and artificial intelligence, are used to this aim and two mathematical model are proposed for satellite fuel mass estimation. By applying the models to several previous satellites, it is shown that the models have lower than 5% average error. The proposed method in this paper is quick and accurate and can be utilized for GEO satellites feasibility study and conceptual design
Vahid Bohlouri; Hosein Haghighi; Samane Kaviri; Marzieh Taghinezhad; ehsan maani; Soheil Seyedzamani
Volume 12, Issue 2 , September 2019, , Pages 55-70
Abstract
In this paper, the design and implementation of hardware-in-the-loop (HIL) test-bed for spacecraft attitude control are presented with respect to the practical consideration. This test-bed includes an air bearing 3-DOF table, Helmholtz coil, sun simulator, orbit simulator, reaction wheels and torqrods ...
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In this paper, the design and implementation of hardware-in-the-loop (HIL) test-bed for spacecraft attitude control are presented with respect to the practical consideration. This test-bed includes an air bearing 3-DOF table, Helmholtz coil, sun simulator, orbit simulator, reaction wheels and torqrods as actuators, gyro, GPS, AHRS, magnetometer, and processing board. In addition, online monitoring of attitude and orbit position in LabVIEW and Celestia software, data telemetry, battery package and power distribution board are developed in this case. Using this test-bed, different operational modes are evaluated and verified for satellite attitude control. The experimental results of damping mode show that the capability of decreasing the angular velocity to the desired value (0.3 deg/s). Moreover, a torque simulator to apply the disturbances and test of propulsion scenarios, online telemetry with ground station, near-optimal design of Helmholtz coil are the advantages of this test-bed.
ehsan maani; Hossein Nejat Pishkenari; Amir Reza Kosari
Volume 11, Issue 3 , December 2018, , Pages 63-71
Abstract
In this paper, the combination of reaction wheels and thrusters is applied to attitude control of a satellite. First, governing equations of satellite attitude dynamics are given using quaternion and PID controller is designed based on the satellite quaternion to determine the applied control torque. ...
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In this paper, the combination of reaction wheels and thrusters is applied to attitude control of a satellite. First, governing equations of satellite attitude dynamics are given using quaternion and PID controller is designed based on the satellite quaternion to determine the applied control torque. By applying the reaction wheels physical constraints such as its maximum torque, its maximum momentum and maximum power on the desired torque, reaction wheels angular momentums and torques are found. The obtained results show that the unsaturated reaction wheels capabilities in attitude control. Results also show that the wheels saturation leads to error in control and increases the Euler angles and quaternions. Satellite thrusters are utilized to reaction wheels de-saturation and attitude control simultaneously.Three different strategies are proposed in this paper for wheels de-saturation using thrusters. Two well known methods, pulse width modulator (PWM) and pulse width pulse frequency (PWPF) modulator are used to attitude control using thrusters. All methods are compared together and the optimal method is proposed for the satellite attitude control. This paper results can be useful in design and control of different class of satellites.
Hadi Hosseini Onari; ehsan maani; Vahid Bohlouri; Soheil Seyedzamani
Volume 10, Issue 4 , March 2018, , Pages 19-28
Abstract
In this study, hardware in the loop (HIL) simulation consisting of solar array simulator, programmable electric load, charger board, distribution board and attitude and position simulator is designed and developed for the mentioned purpose. Because of satellite high angular velocity ...
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In this study, hardware in the loop (HIL) simulation consisting of solar array simulator, programmable electric load, charger board, distribution board and attitude and position simulator is designed and developed for the mentioned purpose. Because of satellite high angular velocity in de-tumbling mode, it is not possible to perform the experimental tests for power consumption analysis. Electricalpower HIL can be used for modifying, redesigning, and verification of the electricalpower subsystem design. The power consumption of communications satellite components is simulated in a de-tumbling mode. De-tumbling mode of operation is implemented in HIL test bed and the experimental results are extracted. The results consisting of battery voltage, battery capacity, current, depth of discharge and voltage stability are investigated. The results of this paper can be useful in the design, implementation and verification of electrical power subsystem for a wide range of satellites from LEO to GEO.
