分析了嵌入式实时调度系统中控制任务的采样周期和延时不规则抖动属性及稳定性能。并且,针对抖动范围有界但抖动属性不能精确已知的离散状态系统,提出一个保守的系统稳定性充分判据。该判据将抖动引起的时变不确定性描述为系统的离散时间闭环区间状态矩阵,利用李雅普诺夫方程和矩阵的无穷范数,导出区间系统鲁棒稳定的充分条件。该方法计算量小且能减小区间代数计算结果易于扩张的问题。仿真算例表明该判据简单有效且能降低保守性。
The stability properties of the embedded real-time scheduling systems whose control loops are subject to sampling and latency jitter are studied. Focused on the discrete state system whose jitters are not exactly known but bounded in intervals, a looser sufficient stability condition is proposed. Thus the time uncertainty is represented as a discrete-time closed-loop interval matrix, and a sufficient robust stability condition using Lyapunov theory and the infinite norm of the matrix is achieved. Furthermore, the overextension in interval computations is eliminated and the computation complexity is low in this proposed method. Simulation results show that the method is more computationally effective and less conservative.