Modeling of control processes of spacecraft orbits with low-thrust engines

Methods of Orbit Clustering of Serviced Spacecraft

System technologies ◽

10.34185/1562-9945-3-122-2019-11 ◽

2019 ◽

Vol 3 (122) ◽

pp. 91-98

Author(s):

Anatolii Petrovych Alpatov ◽

Yurii Mykhailovych Holdshtein

Keyword(s):

Computer Program ◽

Service Operations ◽

Low Thrust ◽

Clustering Technique ◽

Spacecraft Orbits ◽

Orbital Transition

When planning orbital service operations, it is important to rationally divide a set of orbits serviced by a spacecraft into subsets (clusters) of orbits. This article proposes a technique for clustering the orbits of serviced spacecraft in the event of their servicing by a reusable service spacecraft with an electric rocket low thrust engine. The technique is based on the method of K ‑ means. As the distance between any pair of orbits of the serviced spacecraft (metrics) of the method K - means, it was proposed to use the delta-V of the orbital transition between these orbits.In this paper, a technique has been developed for clustering orbits of serviced spacecrafts. The method is based on the method K ‑ means. As a distance between any pair of orbits of the serviced spacecraft orbits (metrics) of the method K ‑ means it is proposed to use the energy metric delta - V of the interorbital transition between these orbits. Using the proposed methodology, a computer program has been developed for clustering the orbits of serviced spacecraft. The results of the test calculations showed the effectiveness of the proposed clustering technique. The technique can be applied when planning orbital service operations.

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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A Bird in the Hand Isn’t Good for Long

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000385 ◽

2018 ◽

Vol 65 (1) ◽

pp. 23-31 ◽

Cited By ~ 2

Author(s):

Stefan Scherbaum ◽

Simon Frisch ◽

Maja Dshemuchadse

Keyword(s):

Decision Making ◽

Cognitive Control ◽

The Other ◽

Decision Task ◽

Short Term ◽

Additional Time ◽

Control Processes ◽

Folk Wisdom ◽

Study Participants ◽

Insight Into

Abstract. Folk wisdom tells us that additional time to make a decision helps us to refrain from the first impulse to take the bird in the hand. However, the question why the time to decide plays an important role is still unanswered. Here we distinguish two explanations, one based on a bias in value accumulation that has to be overcome with time, the other based on cognitive control processes that need time to set in. In an intertemporal decision task, we use mouse tracking to study participants’ responses to options’ values and delays which were presented sequentially. We find that the information about options’ delays does indeed lead to an immediate bias that is controlled afterwards, matching the prediction of control processes needed to counter initial impulses. Hence, by using a dynamic measure, we provide insight into the processes underlying short-term oriented choices in intertemporal decision making.

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