Florin Ionescu

Fuzzy Voronoi diagram for disjoint fuzzy numbers of dimension two

In this paper, we introduce “fuzzy Voronoi” diagrams for fuzzy numbers of dimension two FNDT by extension of crisp Voronoi diagrams for fuzzy numbers. The fuzzy Voronoi sites are defined as fuzzy numbers of dimension two. All the operations are defined in FNDT framework. We propose an analytical approach to compute the boundaries of fuzzy Voronoi diagram for pyramidal-shape FNDT.

Fuzzy-Statistical Reasoning in Fault Diagnosis

When searching for faults threatening a system, the human expert is sometimes performing an amazingly accurate analysis of available information, frequently by using only elementary statistics. Such reasoning is referred to as “fuzzy reasoning,” in the sense that the expert is able to extract and analyse the essential information of interest from a data set strongly affected by uncertainty. Automating the reasoning mechanisms that represent the foundation of such an analysis is, in general, a difficult attempt, but also a possible one, in some cases. The chapter introduces a nonconventional method of fault diagnosis, based upon some statistical and fuzzy concepts applied to vibrations, which intends to automate a part of human reasoning when performing the detection and classification of defects.

Faults Diagnosis through Genetic Matching Pursuit

Signals that carry information regarding the existing defects or possible failures of a system are sometimes difficult to analyze because of various corrupting noises. Such signals are usually acquired in difficult conditions, far from the place where defects are located and/or within a noisy environment. Detecting and diagnosing the defects require then quite sophisticated methods that are able to make the distinction between noises encoding the defects and another parasite signals, all mixed together in an unknown way. Such a method is introduced in this paper. The method combines time-frequency-scale analysis of signals with a genetic algorithm.

A fuzzy-statistical reasoning model for bearings fault diagnosis

When searching for faults threatening a system, the human expert sometimes performs an amazingly accurate analysis of available information, eventually by only using some elementary statistics. Automating the reasoning mechanisms founding such an analysis is, in general, a difficult attempt, but also a possible one, in some cases. The paper aims to introduce a nonconventional method of bearings faults diagnosis, based upon some statistical and fuzzy concepts.

MODELLING AND SIMULATION IN MECHATRONICS

Abstract The paper presents some achievements in complex modelling and simulation in mechatronics, being underlined some characteristics of the mechatronic field together with applications of design principles. Some aspects of the optimized and integrated design having as main part the modelling and simulation of the system are presented. The facilities of the programs used for kinematic and dynamic simulation of multi-body systems are emphasized. Some mechatronic systems are presented as examples of modelling and simulation in MATLAB/Simulink (MS), SolidDynamics (SD) or MotionInventor (MI) programs with accent on robots for micro and nano manipulations of cells, industrial robots, and precessional drives.

Teleoperation Hybrid Robot for Cell Micro and Nano Manipulations

In this paper is presented a developed robotic system for cell micro/nano manipulation and penetration, based on the visual/haptic interface. The operator’s motion and manipulations skills are transferred to the robot control system by direct teleoperation. The robot’s regional structure has three translational joints and one passive rotational joint for the nanorobot adjustment. The three-d.o.f piezo actuated nano robot is a compact and stiff structure, to guarantee the three-dimensional nano motion and control for sample manipulation or injection. The closed kinematic structure with two fundamental loops has been chosen for the required working space, high speed, and precision. The digraph-matroid approach is used for the model’s kinematics, and the SDS software for the robot’s simulation.Copyright

A library of nonlinearities for modeling and simulation of hybrid systems

The present paper is a short review of some of the concepts, procedures and achieved results, oriented toward the modeling of complex, large installations, known under the name of HYPAS. Physical phenomena involved in hydraulic, pneumatic, mechanic and electric systems are depicted by mathematical models (MM) with static and dynamic nonlinearities (NL). This means that, when building large installations, the MM provide multiple NL. They should be completely known in order for the controller to be designed appropriately enough to provide desired behavior, while complying with economical conditions. To facilitate the automatic mathematical model generation, a library with multilayer models was created and are made available. This approach was necessary because the MATLAB® library provides only few general NL. In cases where applicable, neuro-fuzzy techniques were employed for modeling of NL. The paper presents some of the most important results, accompanied by their MATLAB Simulink® representation.

Adaptive recurrent neuro-fuzzy networks based on Takagi-Sugeno inference for nonlinear identification in mechatronic systems

In this paper we propose a recurrent neuro-fuzzy network (RFNN) based on Takagi-Sugeno inference with feedback inside the RFNN for nonlinear identification in mechatronic systems. The parameter optimization of the RFNN is achieved using a differential evolutionary algorithm. The experimental results are analyzed using a study cases modeled in Simulink: the linear power amplifier and the actuator.

Generating Planar Workspace Boundaries by Radius Parsimonious Increase

Abstract This paper addresses the problem of automatic drawing for natural boundaries that result by projecting the specific workspace of a robot on a plane, starting from its Denavit-Hartenberg parameters. The solution is approached by considering that the boundaries are generated by a planar manipulator with the same number of links as the robot. A general algorithm is introduced in case the manipulator has revolute joints. Various robot structures can take benefit from the algorithm, such as a conveyor endowed by artificial vision for assembly-disassembly, which is succinctly described in the end.

A Reconfigurable Fault-Tolerant Communication System for Intelligent Manufacturing Control

Abstract The paper proposes a shared-memory fault tolerant multiprocessor architecture for Computer Aided Manufacturing management and control, where an Ethernet LAN is used to connect FMC associated Station Computers to the shared memory residing in a supervising CAM server. Caches private to the processing elements together with caching protocols minimize the bottleneck effect of the LAN, allowing for efficient parallel off- and on-line processing. A two-level Reconfigurable Switching Network allows for simple downloading of production data, programs and working orders. Using software redundancy, a fault-tolerant behaviour of the Station Computers Network is provided in order to reduce breaks in service of the manufacturing application at shop-floor level.