Synthesis of sampling modes for adaptive control
Rajorshee Raha, Aritra Hazra, Akash Mondal, Soumyajit Dey, P. P. Chakrabarti, Pallab Dasgupta · 2014
Recent studies have shown that adaptively regulating the sampling rate results in significant reduction in the computational resources of embedded software based control. Selecting a uniform sampling rate for a control loop is robust, but pessimistic for sharing processors among multiple control loops. Fine-grained regulation of periodicity achieves better resource utilization, but is hard to implement online in a robust way. However, an offline control theoretic analysis of the system illustrates the benefits of proper period selection for different modes. Such analysis reveals the necessity to automatically derive a multi-mode scheduler and converge on suitable periods for each mode. This paper proposes a methodology to automatically generate such a scheduler for an embedded real-time control system leveraging its design attributes. The proposed method provides significant gains in computational efficiency without trading off the performance.