Distributed group-based vibration control with a networked embedded system

Abstract

The purpose of this work is to demonstrate the performance of a distributed vibration control system based on a networked embedded system. The platform from which control is affected consists of a network of computational elements called nodes. Each node possesses its own computational capability, sensor, actuator and the ability to communicate with other nodes via a wired or wireless network. The primary focus of this work is to demonstrate the use of existing group management middleware concepts to enable vibration control with such a distributed network. Group management middleware is distributed software that provides for the establishment and maintenance of groups of distributed nodes and that provides for the network communication within such groups. The reason for developing distributed control based on group concepts is that communication of real-time sensor and actuator data among all system nodes would not be possible due to bandwidth constraints. Group management middleware provides for inter-node communications among subsets of nodes in an efficient and scalable manner. The objective of demonstrating the effectiveness of such grouping for distributed control is met by designing distributed feedback compensators that take advantage of node groups in order to affect their control. Two types of node groups are considered: groups based on physical proximity and groups based on modal sensitivity. The global control objective is to minimize the vibrational response of a rectangular plate in specific modes while minimizing spillover to out-of-bandwidth modes. Results of this investigation demonstrate that such a distributed control system can achieve vibration attenuations comparable to that of a centralized controller. The importance of efficient use of network communications bandwidth is also discussed with regard to the control architectures considered.