Optimal Integrated Control and Scheduling of Resource-Constrained Systems
In this chapter, we start by studying the problem of the optimal control, for a given fixed finite communication sequence. Then, we have formulated and solved the problem of the joint optimization of control and scheduling, for a given initial state. The numerical examples illustrating this method have pointed out that the obtained optimal schedule is extremely dependent on the chosen initial state x(0). These observations show that in the same way as the optimal control, the optimal scheduling depends on the current state of the system. However, from a computer science point of view, off-line scheduling has many advantages, essentially because it consumes a few computing resources and does not induce execution overheads. In order to obtain off-line schedules that are optimal from a certain point of view, it is necessary to use performance criteria depending on the intrinsic characteristics of the system, not on a particular initial state. This will be the objective of the next chapter. Nevertheless, this dependency between the optimal schedule and the plant state may be seen as promising way for improving the quality of control by means of plant state-based scheduling algorithms. The design of such algorithms will be studied in Chap. 6.
- 14.K.J. Åström, B. Wittenmark, Computer-Controlled Systems: Theory and Design (Prentice Hall, New York, 1997) Google Scholar