Time-scaling method | Proposed method | |
Optimal cost |
17.0752 | 14.2028 |
Optimal switching times |
For a multi-switching system, it consists of multiple parallel switching systems. The optimal control problem controlled by a multi-switching system is to determine the optimal time sequence for each of the parallel switching systems. The time-scaling transformation is a well-known switching time optimization approach which has been widely used in various problem settings. However, the time-scaling transformation requires that these parallel switching systems have the same number of subsystems and are designed to switch simultaneously. Thus, it is not applicable for solving optimal control problems of general multi-switching systems. This paper presents a new technique for optimizing the switching times of multi-switching systems.
Citation: |
Table 1. Optimal costs for Example 1 obtained by using the two techniques
Time-scaling method | Proposed method | |
Optimal cost |
17.0752 | 14.2028 |
Optimal switching times |
Table 2. Optimal costs obtained by using the two techniques for Example 2
Optimal cost |
|||
Using method | |||
Time-scaling method | 1.6632 |
4.0932 |
- |
Proposed method | 1.6632 |
4.0932 |
1.6650 |
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The structure of a switching system
The structure of a multi-switching system
The time-scaling function
The variable switching times to be optimized
The first switching time transformation process
The second switching time transformation process
Optimal state trajectories for Example 1 obtained by using the two techniques
Optimal state trajectories for Case 1 of Example 2 obtained by using the two techniques
Optimal state trajectories for Case 2 and Case 3 of Example 2 obtained by using the traditional time scaling transformation and our proposed methods
Optimal state trajectories for Example 3