Control of Passive Plants with Memoryless Nonlinearities over Wireless Networks

by Nicholas E. Kottenstette This dissertation shows how to develop wireless networked embedded control systems (wnecs) in which the controller and the plant are isolated and can only interact over a wireless network. Many of the new results presented are based on passivity and scattering theory. In particular we show how to: 1. synthesize discrete time passive, strictly-input passive, and strictly-output passive systems from their continuous counterparts using a inner-product equivalent sample and hold (IPESH) block (with an optional passive observer), 2. create a data-drop out, and delay tolerant l-stable digital control network for a continuous passive plant in which: (a) the continuous passive plant can also be subject to various memoryless nonlinearities such as actuator saturation, (b) the digital controller only needs to be run when passive data is received over the wireless network, (c) the entire control network has been simulated on a theoretically validated wireless ring token network, Nicholas E. Kottenstette (d) a new “power junction” is introduced in which multiple plants and controllers can interact while preserving passivity, (e) a new distortion measure is used to evaluate these control networks, 3. determine the capacity, and mean delays of a wireless ring token network. We conclude with a presentation of neclab, a set of python and C based tools used to help an engineer simulate and develop wnecs. To Maryellen, Marie, Therese, and Claire.