Results 271 to 280 of about 410,560 (293)

LOW CONSTANT TANGENTIAL THRUST SPIRAL TRAJECTORIES

AIAA Journal, 1963
The stroboscopic method in nonlinear mechanics is applied to the calculations of a low constant tangential thrust spiral trajectory in a single force field. Closed-form solutions for the first approximation are derived. The oscillatory nature of the spiral is exposed; the maximum deviation of the oscillation is of the order of 2/A, where I/A is the ...
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OPTIMUM LOW-THRUST RENDEZVOUS AND STATION-KEEPING

Summer Meeting, 1963
Analytic solutions are determined for the optimum correction of all six elements of elliptic satellite orbits with low-thrust, power-limited propulsion systems. The optimum direction and magnitude of thrust are determinedas functions of time so as to minimize the fuel required to rendezvous in a given time or to minimize the fuel required for station ...
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A CONTINUOUS PROPORTIONAL LOW-THRUST PROPULSION SYSTEM

IFAC Proceedings Volumes, 1989
Helium gas flows continuously from a low temperature dewar supplying propellant for satellite thrusters. Thrust is obtained by movement of a spool located between two opposing nozzles thus differentially restricting the helium flow. The design procedure and test results of a high bandwidth, low power, linear electromagnetic actuator for the spool ...
J.-H. Chen, J. Bull, D.B. DeBra
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Optimal, Low-Thrust, Earth-Moon Orbit Transfer

Journal of Guidance, Control, and Dynamics, 1998
We find optimal, low-thrust, Earth-Moon orbit transfers by using the method of collocation with nonlinear programming. The initial spacecraft Earth orbit is arbitrary; the final lunar orbit is arbitrary. The Moon is in its actual orbit. The vehicle dynamics include the effect of Moon's gravity during the Earth-departure phase and the effect of Earth's ...
Herman, Albert L., Conway, Bruce A.
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Two Direct Low Thrust Trajectory Optimization Techniques

Journal of Computer and Systems Sciences International, 2018
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Trofimov, S. P., Tselousova, A. A., Shirobokov, M. G.   +2 more
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Low thrust insertion into orbit around Mars

25th AIAA Aerospace Sciences Meeting, 1987
References Juang, J. M, Turner, J. D., and Chun, H.M., "Closed-Form Solutions for a Class of Optimal Quadratic Regulator Problems with Terminal Constraints," ASME Journal on Dynamics, Measurement, and Control, Vol. 108, March 1986. Reid, J. C., Maybeck, P. S., Asher, R.B., and Dillow, J.
S. A. Parvez, J. M. L. Holman
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Thrust Magnitude Constraint Handling for Low-Thrust Trajectory Optimization

Journal of Spacecraft and Rockets
A detailed analysis of six control constraint methods for thrust magnitude limitations is presented. The inequality augmented Lagrangian and penalty inequality augmented Lagrangian methods are widely used, whereas the box, Heaviside augmented Lagrangian, and penalty Heaviside augmented Lagrangian methods are less common.
Bryn Fanger, Ryan P. Russell
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Automated Missed-Thrust Propellant Margin Analysis for Low-Thrust Trajectories

Journal of Spacecraft and Rockets, 2015
Spacecraft employing low-thrust propulsion must be able to recover from an event in which the spacecraft stops thrusting due to an unforeseen problem. Extra propellant is carried to allow the spacecraft to reach its target in the form of propellant margin.
Frank E. Laipert, James M. Longuski
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High and low thrust acceleration

Acta Astronautica, 1983
Abstract For rocket transfers between coplanar circular orbits various areas of flight mechanical interest are outlined, depending upon thrust acceleration. Optimum thrust direction has been assumed. All information presented has been derived from analytical approximations.
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Small centrifugal pumps for low-thrust rockets

Journal of Propulsion and Power, 1985
This paper presents the results of a combined analytical and experimental investigation of low specific speed pumps for potential use as components of propellant feed systems for low thrust rocket engines. Shrouded impellers and open face impellers were tested in volute type and vaned diffuser type pumps.
N. GULBRANDSEN, R. FURST, R. BURGESS, D. SCHEER   +3 more
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