Scheduling system of low earth orbit (LEO) satellite operations is one of the important tasks performed in satellites. Satellite specific constraints, satellite priorities, priorities of certain payload and special operations, as well as visibility conflicts are taken into consideration while generating the operations schedules in an optimum way. This paper proposes a tabu search heuristic for earth observation satellite scheduling problem, where as earth observing operations have to be scheduled on several resources while respecting time constraint and taking the priorities of the operations into account with the objective of scheduling as many operations as possible within its time window. The computational results indicate that this approach is typically effective to generate a near optimal and feasible schedule for imaging operations of the satellite.

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Scheduling system of low earth orbit (LEO) satellite operations is one of the important tasks performed in satellites. Satellite specific constraints, satellite priorities, revenue of certain payloads and special operations, as well as visibility conflicts are taken into consideration while generating the operations schedules in an optimum way. This paper uses graph coloring problem for earth observation satellite scheduling, where as earth observing operations have to be scheduled on several resources while respecting time constraint and taking the revenue of the operations into account with the objective of scheduling as many operations as possible within its time window. Then a tabu search heuristic is proposed for this coloring problem. The computational results indicate that this approach is typically effective to generate a near optimal and feasible schedule for imaging operations of the satellite.

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Attitude Determination and Control Subsystem (ADCS) is one of the vital subsystem of satellites which has a significant role in performing satellites missions. On-Board Electronic (OBE) is the main part of this subsystem which executes attitude determination and control algorithms. In this paper design of OBE of ADCS in IUST-SAT is presented. Design of this equipment is carried out based on requirements and constraints which are extracted by hierarchical design procedure. Satisfying design constraints and achieving functional requirements simultaneously, is a major task, which is carried out successfully in this paper. Also for verification of performance of this equipment before a satellite's launch, in this paper a novel and low-cost real-time hardware in the loop test bed is provided. The presented test bed is capable of assessing ADCS's equipments in a real-time condition. Finally, performance of designed OBE is investigated by implementing detumbling and initial attitude acquisition control modes in the hardware in the loop test bed.