Title :
Managing quality-of-control performance under overload conditions
Author :
Buttazzo, Giorgio ; Velasco, Manel ; Marti, Pau ; Fohler, Gerhard
Author_Institution :
Pavia Univ., Italy
fDate :
30 June-2 July 2004
Abstract :
A common method for dealing with overload conditions in periodic task systems is to reduce the load by enlarging activation periods. When a periodic task implements a digital controller, however, the variation applied on the task period also affects the control law, which needs to be recomputed for the new activation rate. If computing a new control law requires too much time to be performed at runtime, a set of controllers has to be designed offline for different rates and the system has to switch to the proper controller in the presence of an overload condition. In this paper, we present a method for reducing the number of controllers to be designed offline, while still guaranteeing a given control performance. The proposed approach has been integrated with the elastic scheduling theory to promptly react to overload conditions. The effectiveness of the proposed approach has been verified through extensive simulation experiments performed on an inverted pendulum.
Keywords :
control engineering computing; control system synthesis; controllers; digital control; pendulums; periodic control; processor scheduling; resource allocation; control law; digital control; elastic scheduling; inverted pendulums; overload conditions; periodic task systems; quality-of-control management; Computational modeling; Control system synthesis; Control systems; Degradation; Digital control; Processor scheduling; Quality management; Real time systems; Runtime; Switches;
Conference_Titel :
Real-Time Systems, 2004. ECRTS 2004. Proceedings. 16th Euromicro Conference on
Print_ISBN :
0-7695-2176-2
DOI :
10.1109/EMRTS.2004.1310999