## 3 Proposed Methods
### Reasoning-Based Scheduling Method
#### 3.2.2 Rule-Based Reasoning and Target Weight Calculation  
Mission scheduling determines the observation path through the selection of different targets. A common scheduling method is to adjust the selection order of targets by determining the weights of the targets. We assigned different weights to targets under different satellite coupling states to realize the switching of the scheduling strategy.  
We described the strategy selection as the reasoning rules under different satellite coupling states and reason as the target's flags of preference including the data transmission and electricity flags. Next, we recorded the serial number of the location segment for each target as \(Seg_{i}=l\quad t_{sl}\leq t_{ti}<t_{el}\), and the reasoning rules for the flag of preference of each target can be expressed as follows:  
**IF**\(StatusM_{Segi}=insufficient\)**OR**\(\hat{M}_{outTotal}>\hat{M}_{inTotal}\)  
**THEN**\(flag_{datatrans}^{l}=1\)  
**IF**\(StatusM_{Segi}=sufficient\)**AND**\(\hat{M}_{outTotal}\leq\hat{M}_{inTotal}\)  
**THEN**\(flag_{datatrans}^{l}=0\)  
**IF**\(W_{initial}+\hat{W}_{in}<\hat{W}_{out}\)  
**THEN**\(flag_{ele}=1\)  
**IF**\(W_{initial}+\hat{W}_{in}\geq\hat{W}_{out}\)  
**THEN**\(flag_{ele}=0\)  
From the above reasoning rules, when the predicted memory capacity state is low or the predicted total available data transmission volume is less than the predicted total observation data volume in segment \(l\), the target is given a flag that has more preference to data transmission \(flag_{datatrans}^{l}=1\), otherwise the target is given a flag that has less preference to data transmission \(flag_{datatrans}^{j}=0\). When the sum of the satellite initial electrical energy and the predicted charging electrical energy is less than the predicted total electrical energy consumption, the target is given a flag that has more preference to electricity \(flag_{ele}=1\), otherwise the target is given a flag that has less preference to electricity \(flag_{ele}=0\).  
The weight of targets is calculated based on the preferred flag of targets, which is defined as  
\[w_{i}=c_{o}\frac{v_{i}\mathrm{max}\Big{(}\Delta t_{lbs,i}^{p}\Big{)}}{t_{e}-t_ {s}}+c_{d}flag_{datatrans}^{i}status_{datatrans}^{i}+c_{e}flag_{ele}\big{(}1- \big{|}\varphi_{power}-\varphi_{i}\big{|}\big{)}, \tag{22}\]  
where \(w_{i}\) is the selection weight of target \(i\), and \(c_{o}\), \(c_{d}\), and \(c_{e}\) are the coefficients. The first item on the right side of Equation (22) is the product of the maximum backward time slack index and the target profit, where the higher the value this item has, the selection of this target enables the observation result sequence to have more backward time slack, which is more conducive to observation. Note that the calculation of the maximum backward time slack can be found in Appendix C. When \(flag_{datatrans}^{i}=1\), the favorable target for data transmission is given a higher weight, which is more conducive to the data transmission. In the third item of Equation (22), \(\varphi_{i}\) and \(\varphi_{power}\) are the roll angles at which the satellite observes target \(i\) and can obtain the maximum charging electrical power, respectively. From the coupling analysis in Section 3.1, it was noticeable that when the satellite's orbital plane was more parallel to the Sun vector, the favorable target for electricity is closer to the satellite's sub-satellite point; conversely, this target is further away from the satellite's sub-satellite point. The closer \(\varphi_{i}\) is to \(\varphi_{power}\), the greater the charging electrical power satellite can obtain. When \(flag_{ele}=1\), the target that the satellite can obtain more electrical power from while observing is more conducive to the electricity.