Decomposition of the flight plan to target fragments as an effective method for improving of automatic spacecrafts work planning procedure

Аuthors

Zhigastova O. K.^*, Pochukayev V. N.

Central Research Institute of Machine Building, 4, Pionerskaya st., Korolev, Moscow region, 141070, Russia

*e-mail: inolga-ok@yandex.ru

Abstract

The article is dedicated to improving of automatic spacecraft flight planning procedure. The proposed method is based on decomposition of the flight plan into a set of target fragments. The target fragment concept is connected to the feature of the functioning and executing of the spacecraft targets tasks. Automatic flight control of the spacecraft can be considered as control of its space-time condition [1], which ensures the achievement of the spacecraft targets tasks. Design/methodology/approach
The initial data for automatic spacecrafts flight planning is the scenario of space-time actions [1]. Under the action we mean operations performed on the spacecraft and resulted in changes of its space-time condition. According to this each flight plan targeting fragment should be consist of a sequence of control commands, which provide the execution of one of the operations included in the space-time action plan.
Different target fragments of the flight plan have a similar structure. It is determined by specific features of commands, which are included in the target fragment. So the first command of the target fragment must be fully supported by the original data needed to initiate a whole sequence of commands. The execution of the last target fragment command means that all the previous track commands were executed and the necessary space-time conditions were created for the functioning of the target equipment, the operation of which will provide the reach of next spacecraft target. The sequence of commands in the target fragment should be satisfied to the requirement of cause-and-effect relationship.
An important feature of the flight plan target fragments is that they are independently of each other.
It is necessary to perform an «addition» operation of target fragments in order to receive the final flight scenario of an organized target fragments sequence. Thus, the flight plan may be provided in two forms: as a sequence of the target fragment and as integrally transmitted to the SC for its execution.
Findings
The feature of flight plan storing simultaneously in two forms has several important advantages. They are as follows:
At first transformation of the flight plan consisted from target fragments into the integral plan performed by «addition» operation, which is simple operation and can be automated.
At second the presentation of the flight plan in its original form gives:
- ease of target fragments preparation in an automated version;
- significant simplification of the correction operation plan, the necessity for which arises during the execution of spacecraft flight plan. This procedure involves three steps: change only within a given target fragment without touching the other fragments of the flight plan, exclusion of target fragment from the plan addition of new target fragment into the plan. After performing these steps corrected plan is formed again by «addition» operation of target fragments;
- keeping the plan as a sequence of target fragments can significantly simplify the «merging» operation between current flight plan and plan compiled in regular time interval. To do this it is sufficient to add the target fragments taken from the new plan accordingly to their precedence into the current plan.
Research limitations/implications
The proposed method of flight plan creating can greatly simplify the planning procedure as for non- automated plan creating and for its automated execution. It can be used for flight control of unmanned and manned spacecrafts.
Originality/value

1. Target fragments occupy animportant place inthe general procedure ofcomputerize flight planning ofautomatic spacecrafts. They allow tomake the procedure offlight plan creating more clearer and transparent.
2. The using oftarget fragments gives anew way tolook atthe very procedure ofcreating aflight plan and execution ofoperations onits correction.
3. During the flight plan creating the main focus isonflight plan correcting operation and «merging» operation. Using the basic property oftarget fragments— the link offinal command with aspace-time action, itispossible tointroduce the newly created plan inthe existing structure ofactive flight plan.

Keywords:

spacecraft, flight planning, flight plan, control commands, flight plan target fragment, cause- and-effect relationships

References

1. Zhigastova O.K., Pochukaev V.N. Elektronnyi zhurnal «Trudy MAI», 2011, no. 49, available at: http://www.mai.ru/science/trudy/eng/published. php?ID=28296 (accessed 27.12.2011).
2. Zhigastova O.K., Pochukaev V.N. Elektronnyi zhurnal «Trudy MAI», 2011, no. 49, available at: http://www.mai.ru/science/trudy/eng/published.php?ID=28206 (accessed 27.12.2011).
3. Zhigastova O.K., Pochukaev V.N. Vestnik Moskovskogo aviatsionnogo instituta, 2012, vol. 19, no. 3, pp. 97-103.