The development of research spacecraft systems has a significant impact on the preparation and simulation of future space missions. Hardware, software and operation procedures can be properly tested, validated and ver...
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ISBN:
(数字)9781624106095
ISBN:
(纸本)9781624106095
The development of research spacecraft systems has a significant impact on the preparation and simulation of future space missions. Hardware, software and operation procedures can be properly tested, validated and verified before they are deployed for an actual mission. In this paper, a spacecraft vehicle testbed named Extreme Access System is introduced. The system has been developed to support validation and verification of guidance, navigation and control algorithms. Description of the spacecraft testbed, subsystems and integration is presented in this paper along with an analysis of results from numerical simulation and actual implementation of control laws. An attitude control architecture based on a Quaternion Feedback Linearization based controller is also described and performance analysis in the compensation of undesired dynamics is presented to demonstrate capabilities and potential missions that can be simulated using this system.
This paper presents a novel strategy for attitude control of a spinning spacecraft in low Earth orbit (LEO) using only magnetorquers. The work has been developed within the Alpha CubeSat mission at Cornell University,...
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ISBN:
(数字)9781624106095
ISBN:
(纸本)9781624106095
This paper presents a novel strategy for attitude control of a spinning spacecraft in low Earth orbit (LEO) using only magnetorquers. The work has been developed within the Alpha CubeSat mission at Cornell University, and is embedded in the flight computer of the 1U CubeSat. The attitude-control algorithms shall accomplish two separate maneuvers to (1) detumble and spin the satellite about its maximum principal axis of inertia with a desired magnitude, and (2) align the spin axis with the Earth's magnetic field lines. Specifically, a nonlinear control law based on energy-dissipation principles manages the detumbling and spinning phase, while a linear PD control law achieves alignment with the external magnetic field lines. Stability analysis and simulation of these control laws has been conducted through MALTAB & Simulink.
This work presents novel progressive and adaptive dynamic geometry control algorithms which seek to improve convergence and reduce userworkload by partially automating the design of effective geometry control systems ...
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ISBN:
(数字)9781624106101
ISBN:
(纸本)9781624106101
This work presents novel progressive and adaptive dynamic geometry control algorithms which seek to improve convergence and reduce userworkload by partially automating the design of effective geometry control systems for aerodynamic shape optimization. These algorithms function by beginning in a coarse design space and periodically refining the geometry control with additional design variables when objective improvement becomes asymptotic. When refinement is initiated, progressive geometry control moves through a pre-defined sequence of increasingly fine geometry control schemes, while the adaptive algorithm instead dynamically generates a refined search space. This is accomplished by generating a list of candidate refinements and ranking them based on the minimum of a constrained quadratic suboptimization problem which constitutes an estimate of the maximum objective reduction possible in each candidate search space. The accuracy of this method is first validated on two inviscid problems, after which the progressive and adaptive algorithms are applied to two common aerodynamic shape optimization problems based on the Reynolds-Averaged Navier-Stokes equations, the twist and section optimization of the common research model wing-only geometry, and the planform optimization of a hybrid wing-body aircraft. In both cases, the dynamic geometry control schemes are able to converge to lower drag, often with fewer optimization iterations, compared to the tested static schemes.
The condition of the loading process research, working out the principles and installations of automatic control of supplying the loading machines with grabbing claws is considered. The experience of application of di...
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ISBN:
(纸本)9781510816879
The condition of the loading process research, working out the principles and installations of automatic control of supplying the loading machines with grabbing claws is considered. The experience of application of discrete control system with regulated upper and lower levels of turning in the adjusters of loading the grabbing part engines is based. The task of automatic control providing, with the consideration of occasional character of forming the load with the grabbing claws, the achievement of maximum productivity at keeping power and energy limits, is formulated. The necessary mathematical models and control algorithms, the peculiarity of which is preliminary modeling of the process, putting the results into the system of microprocessing control and consideration of deviations from the standard variant, are worked out. Using the offered system provides with the productivity increase up to 15 %, increasing the reliability and reducing labour capacity in the machine control. (C) 2015 The Authors. Published by Elsevier Ltd.
In order to help undergraduates to study automatic control theory, and provide a common experiment platform based Internet for postgraduates to do research on control algorithm, we built a novel MATLAB & Internet ...
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ISBN:
(纸本)9781424427239
In order to help undergraduates to study automatic control theory, and provide a common experiment platform based Internet for postgraduates to do research on control algorithm, we built a novel MATLAB & Internet Based Remote control Laboratory (M_I_RCLAB). In the laboratory, Students can make use of M-language to do simulation experiments and demonstration practicality experiments of automatic control theory in browser. In addition, students can design their own controller and upload the controller to M_I_RCLAB to do the remote real-time control experiment. Examples of a cases study of uploading PID and LQR controller for remote real-time control inverted pendulum are shown in the paper.
The mathematical model for three-phase four-leg grid-connected inverter is modeled by the simplified p-q-r theory. The control strategy is proposed based on the characteristic of controlled variables. PI algorithm is ...
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ISBN:
(纸本)9783037853191
The mathematical model for three-phase four-leg grid-connected inverter is modeled by the simplified p-q-r theory. The control strategy is proposed based on the characteristic of controlled variables. PI algorithm is adopted for variables of p axis and q axis, and PR algorithm is adopted for variable of r axis. The full design and analysis of the proposed control algorithms are given in this paper. Simulation results and experimental result show that quality of four-leg grid-connected inverter output current is higher, and effectiveness of the proposed control strategies is validated by all results.
Development of Electric Vehicles (EV) makes a huge step forward to complete transition from conventional fossil fuel driven vehicles to modern, renewable energy based vehicles. Integration of large capacity charging s...
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ISBN:
(纸本)9781538670736
Development of Electric Vehicles (EV) makes a huge step forward to complete transition from conventional fossil fuel driven vehicles to modern, renewable energy based vehicles. Integration of large capacity charging stations (CS), specially developed for plug-in electric vehicles, into smart grid concept of distribution system is analyzed in this paper. Electric vehicles are considered not only as controllable loads but also as significant resource for peak demand control. In that manner proposed optimization framework is developed and implemented using genetic algorithm. Proposed optimization procedure is tested on different case studies. Simulation results, together with proposed optimization framework and derived conclusions could serve as basis of different short-term planning studies or even for development of real time control algorithms.
The article discuss algorithms for controlling electromagnetic actuators (EMAs) of a resonant type which are oriented at controlling the valves of units of autonomous transport systems and provide stable operation of ...
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ISBN:
(纸本)9781538643075
The article discuss algorithms for controlling electromagnetic actuators (EMAs) of a resonant type which are oriented at controlling the valves of units of autonomous transport systems and provide stable operation of the electromagnetic mechanism under vibration conditions. The feature of the proposed algorithms is the absence of specialized position sensors, speed or acceleration of the movable actuator element which excludes the existence of additional frictional forces in the mechanism, simplifies the design, increases the service life and reliability of EMAs in general. The algorithms are based on the interconnection of electrical processes taking place in the winding of the electromagnetic actuator with mechanical processes caused by the movement of the movable element of the magnetic system. The transient characteristic of the control signal in the coil of the electromagnet is presented, and a method for determining the duration of the time intervals and the rate of current change in real time for forming a transient characteristic of the control signal, under the condition of the minimum value of the final velocity of the valve, is considered. The efficiency of the application of the proposed control algorithms for the EMAs of the air pulse valve was tested experimentally on a test bench with an internal combustion engine. The test results showed that the application of the proposed algorithms allows to provide a final valve landing speed of less than 0.4 m/s and a switching time of about 3.6 ms under the external disturbance.
The control principle of mobile robots, self-organized in convoy structure, is considered. It is shown that in this case a high autonomy of swarm operation may be achieved, due to such parameters of motion, as swarm a...
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ISBN:
(纸本)9783031097263;9783031097263
The control principle of mobile robots, self-organized in convoy structure, is considered. It is shown that in this case a high autonomy of swarm operation may be achieved, due to such parameters of motion, as swarm azimuth angle and velocity of movement may be set only for the master robot, while slave robots follow master one at the pre-determined distance. The flowchart of the swarm control system is worked out, according which all slave robots measure their own deviation from the direction on previous swarm unit and distance till it, and actuate mechanics of the robot for zeroing azimuth angles difference and setting pre-determined distance. Mathematical models of the swarm, as the united object under control, and of the distributed Von Neumann controller, which closes control system, are worked out. It is shown, that characteristic equation of closed system have complex exponent at the left side, which is due to time delays, born by Von Neumann type controllers. Method of evaluation of time delays, based on semi-Markov simulation of control algorithm, is proposed. Theoretical results are confirmed by modeling the motion control of a convoy, including pair mobile robots.
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