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Showing 1 to 14 of 14 for “"Gravity assist"”.
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Satellite Deceleration Using Gravity Assist from Asteroid
<p>Satellites have used gravity assists to increase their speed when exploring the solar system. This same maneuver can be done but with the objective to slow down the satellites. This has been theorized to slow down asteroids using the moon to capture them in earth’s orbit. My goal is to determine …
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Analytical methods for gravity-assist tour design
… develops analytical methods for the design of gravity-assist space- craft trajectories. Such trajectories are commonly employed by planetary science missions to reach Mercury or the Outer Planets. They may also be used at the Outer Planets for the design of science tours with multiple flybys of …
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Robust preliminary design for multiple gravity assist spacecraft trajectories
… address specific contributions to the multiple gravity assist trajectory optimization state-of-the-art, however, each one is also an important component of a modern trajectory design paradigm and is valuable for its ability to be integrated with and streamline that process as a whole. The …
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Global Optimization of MGA-DSM Problems Using the Interplanetary Gravity Assist Trajectory Optimizer (IGATO)
<p>Interplanetary multiple gravity assist (MGA) trajectory optimization has long been a field of interest to space scientists and engineers. Gravity assist maneuvers alter a spacecraft's velocity vector and potentially allow spacecraft to achieve changes in velocity which would otherwise be …
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Efficient Trajectory Optimization Procedure for Designing Solar -Electric Propulsion, Gravity -Assist Outer -Planet Missions
A performance (delivered mass versus time of flight) estimation technique approximates the performance of different revolution ratio trajectories from a set of optimal trajectories using a linear least square fitting method. This technique brings further understanding of the effect of different …
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Spacecraft Trajectory Optimization Suite (STOpS): Optimization of Multiple Gravity Assist Spacecraft Trajectories Using Modern Optimization Techniques
… is to minimize propellant mass via multiple gravity assist maneuvers (MGAs). Some computer programs have been developed to analyze MGA trajectories. One of these programs, Parallel Global Multiobjective Optimization (PaGMO), uses an interesting technique known as the Island Model Paradigm. …
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Gravity-assist trajectories to Venus, Mars, and the ice giants: Mission design with human and robotic applications
<p>Gravity-assist trajectories to Uranus and Neptune are found (with the allowance of impulsive maneuvers using chemical propulsion) for launch dates ranging from 2024 to 2038 for Uranus and 2020 to 2070 for Neptune. Solutions are found using a patched conic model with analytical ephemeris via the …
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Design of low-thrust missions to asteroids with analysis of the missed-thrust problem
… asteroid Kleopatra, Mars and Earth are useful gravity assist bodies, with payload masses of 950-1150 kg possible using a 20 kW solar electric propulsion system. A mission to the Jupiter Trojan asteroids would be well-served by visiting two objects. The pair 1986 TS6 and Hektor stand out as …
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Machine learning-aided trajectory optimization and tour design
… for interplanetary missions involving multiple gravity assists. In early-stage trajectory analysis, the repeated solution of Lambert’s problem often becomes a major computational bottleneck. Meanwhile, the number of possible flyby sequences grows combinatorially as the number of flybys …
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Orbital Optimization of Interplanetary Trajectories with Environmental Perturbations
… a flyby section was created for the hyperbolic gravity assist trajectories. A cost function was then used to evaluate the best combination of Delta V, time of flight, synodcity, flyby altitude, and heliocentric energy. This work is primarily concerned with adding the dynamics created by …
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Spacecraft Trajectory Optimization Suite: Fly-Bys with Impulsive Thrust Engines (Stops-Flite)
… costs is the utilization of one or multiple gravity assists. Due to the phenomenon known as the Oberth effect, fuel burned at a high velocity results in a larger change in orbital energy than fuel burned at a low velocity. Since a spacecraft is flying fastest at the periapsis of its orbit, …
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Automated trajectory planning for multiple-flyby interplanetary missions
… Δv at the periapse of each flyby. These Multiple Gravity Assist (MGA) trajectories are optimized using a cooperative algorithm of Differential Evolution (DE) and Particle Swarm Optimization (PSO). The second class of trajectories, known as Multiple Gravity Assist with one Deep Space Maneuver …
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Use of Manifolds in the Insertion of Ballistic Cycler Trajectories
… specif- ically – was completed. The required gravity assist maneuvers at each planet was analyzed through V∞ matching and the entire trajectory was generated over the re- quired inertial period. This method allowed for the generation of 2 cycler trajectories of the inbound and outbound …
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Interplanetary Trajectory Optimization with Automated Fly-By Sequences
… analyze interplanetary trajectories for multiple gravity assist (MGA) missions. One limitation of STOpS and other spacecraft trajectory optimization programs (GMAT and Pygmo/Pagmo) is that they require a defined encounter body sequence to produce a constant length set of design variables. Early …