Ioannis Raptis

2papers

2 Papers

SYSep 23, 2016
A Particle-Filtering Based Approach for Distributed Fault Diagnosis of Large-Scale Interconnected Nonlinear Systems

Elaheh Noursadeghi, Ioannis Raptis

This paper deals with the problem of designing a distributed fault detection and isolation algorithm for nonlinear large-scale systems that are subjected to multiple fault modes. To solve this problem, a network of communicating detection nodes is deployed to monitor the monolithic process. Each node consists of an estimator with partial observation of the system's state. The local estimator executes a distributed variation of the particle filtering algorithm using the partial sensor measurements and the fault progression model of the process. During the implementation of the algorithm, each node communicates with its neighbors by sharing pre-processed information. The communication topology is defined using graph theoretic tools. The information fusion between the neighboring nodes is performed by means of a distributed average consensus algorithm to ensure the agreement over the value of the local likelihood functions. The proposed method enables online hypothesis testing without the need of a bank of estimators. Numerical simulations demonstrate the efficiency of the proposed approach.

ROApr 15, 2016
Dynamic Endpoint Object Conveyance Using a Large-Scale Actuator Network

Martin Sinclair, Ioannis Raptis

Large-Scale Actuator Networks (LSAN) are a rapidly growing class of electromechanical systems. A prime application of LSANs in the industrial sector is distributed manipulation. LSAN's are typically implemented using: vibrating plates, air jets, and mobile multi-robot teams. This paper investigates a surface capable of morphing its shape using an array of linear actuators to impose two dimensional translational movement on a set of objects. The collective nature of the actuator network overcomes the limitations of the single Degree of Freedom (DOF) manipulators, and forms a complex topography to convey multiple objects to a reference location. A derivation of the kinematic constraints and limitations of an arbitrary multi-cell surface is provided. These limitations determine the allowable actuator alignments when configuring the surface. A fusion of simulation and practical results demonstrate the advantages of using this technology over static feeders.