Satellite Mission Instruction Sequence Generation Algorithm Using a Flexible Weighted Directed Graph
Algorithm 1
Instruction sequence generation algorithm based on the directed acyclic graph model.
1. Hierarchizing the graph according to the following definition.
(i) Define as vertex;
(ii) vertices only take the vertices as forward vertices;
(iii) vertices only take the vertices or as forward vertices;
(v) ...
(vi) vertices take ,, …, vertices as forward vertices;
2. Start with , the earliest execution time interval of each vertex relative to is computed by layer;
3. The earliest execution time interval of relative to is the minimum execution time of the task instruction sequence;
4. Starting from , the latest execution time interval of each vertex relative to is calculated in reverse step by step;
5. For instruction like shutdown, the execution time delay selects the earliest execution time interval relative to , and for instruction like switch on, the execution time delay selects the latest execution time interval relative to ; Ensure that the command sequence satisfies the user’s task, starting as late as possible and shutting down as early as possible;
6. The execution time of the vertices is the time subtracts the earliest execution time of the to , which is also the start time that the sequence starts to execute;
