Mechatronic design for component-swapping modularity using bi-directional communications in networked control systems

Availability of low cost electronics has led to a new type of control system components, so called "smart" components, which can perform control actions in the actuator and sensor components as well as in the controller. The objective of our research is to improve component swapping modularity of feedback control system components by utilizing smart such components, and the bi-directional network communications among these components. Control systems that are designed to have modularly swappable components can be re-configured, by changing their components, and still can operate at their optimal closed loop performance by only re-designing the control algorithm that resides in the component that is being changed.;As a first step, a quantification measure for swapping-modularity of single component and an optimal design formulation that maximizes component swapping modularity are presented. The developed method is then demonstrated with a driveshaft speed control example where the component swapping modularity of the actuator (i.e. dc-motor and gearbox smart component) is maximized. The effects of communication and computation constraints on the resulting component-swapping modularity are also investigated.;The problem formulation originally developed for single input single output (SISO) controllers and continuous time systems is then extended to apply to multiple input multiple output (MIMO) controllers with discrete-time formulations. A control oriented pre-optimization, technique, based on pole zero locations which simplifies numerical solution of the optimization problem is developed. The method is then applied to the distribution of a discrete MIMO controller for a Variable Camshaft Timing (VCT) Engine to improve the component swapping modularity of the VCT and the Exhaust Gas Oxygen (EGO) Sensor components using network communications.;Development of measures for combined swapping modularity is important to be able to analyze more complex engineering cases. As the final research topic, two approaches (simultaneous and sequential) for combining component swapping modularity of two or more components are discussed. These combined modularity approaches are used to design controllers which maximize the component-swapping modularity of the VCT component and the EGO sensor for an internal combustion engine as an example.