Ad Hoc Networks of Embedded Control Systems

这个项目评估在何种程度上，特设网络的嵌入式系统（NEST）可用于实现反馈控制系统。 Ad hoc NEST价格低廉且易于部署，但其ad hoc性质使得不可能实现硬实时反馈控制器。 因此，NEST反馈控制系统是软实时系统，其中反馈测量被延迟或丢弃。 在这种软实时环境中保持特定水平的整体闭环性能是极具挑战性的。 该项目将开发确保NEST系统整体闭环性能的方法。 这一目标将通过采用一种跨学科的方法来实现，这种方法将控制、实时系统、计算机系统和通信方面的研究工作结合起来。 特别地，该项目通过以下方式解决该问题：1）使用最小跳数路由方案的多项式扩展的连接的动态重新路由，2）其行为可以直接与闭环控制器性能相关的新颖的软调度方法的开发，（3）动态重构通过使用组合信道编码和ARQ方法来分配链路容量。该项目的广泛影响将通过一门本科课程来表达，将控制理论概念与嵌入式系统原理相结合。 进一步的项目影响将通过协调这项工作与现有的DARPA合同，正在开发的NEST型系统的中间件技术实现。

This project evaluates the extent to which ad hoc networks of embedded systems (NESTs) may be used to implement feedback control systems. Ad hoc NESTs are inexpensive and easy to deploy, but their ad hoc nature makes it impossible to realize feedback controllers in hard real-time. NEST feedback control systems, therefore, are soft real-time systems in which feedback measurements are delayed or dropped. Maintaining specified levels of overall closed loop performance in such a soft real-time environment is extremely challenging. This project will develop methods for assuring overall closed loop performance in NEST systems. This goal will be achieved by adopting a cross-disciplinary approach that integratesresearch efforts in control, real-time systems, computer systems, and communications. In particular, the project tackles this problem by 1) the dynamic re-routing of connections using a polynomial extension of minimum hop routing schemes, 2) the development of novel soft scheduling methods whose behavior can be directly related to closed loop controller performance, and 3) the dynamic re-allocation of link capacities through the use of combined channel coding and ARQ methods.The project's broader impacts will be expressed through an undergraduate level course that integrates control theory concepts with embedded system principles. Futher project impacts will be realized by coordinating this work with an existing DARPA contract that is developing middleware technologies for NEST-type systems.