Search results for " machine"
showing 10 items of 1317 documents
Testing of cooperative tasks for Unmanned Aerial and ground platforms
2014
In the last years the Model Based Design for Unmanned Systems aided the safe and rational release of applications running on unmanned systems. In particular in this paper we focus on a hybrid methodology that merges Software in the Loop (SIL) and Model in the Loop (MIL) strategies for cooperative tasks performed by aerial and ground autonomous vehicles. The proposed work flow covers the design and testing of Ground Control Station (GCS) modelled by a finite state machine, the design and testing of navigation code running on UAV and UGV and the testing of cooperative missions. The work-flow is based on a realistic 3D physical simulator interfaced with Matlab-Simulink-Stafeflow. The proposed …
Application of latent nestling method using Coloured Petri Nets for the Fault Diagnosis in the wind turbine subsets
2008
This paper presents an application example using the lating nestling method for the fault diagnosis based in the use of coloured Petri nets, to a lubrication and cooling system in the wind turbinepsilas gearbox with a critical subsystem as far as failure probability. It demonstrate the synthesis capacity of the method for any model of diagnosis and isolation, giving as opposed to know the contributed advantages other methodologies, as those based in finite state machine.
Latent Nestling Method: A new fault diagnosis methodology for complex systems
2008
This paper presents a new methodology for permanent and intermittent fault diagnosis, named faults latent nestling method (FLNM), using coloured Petri nets (CPNs). CPNs and FLNM method allow for an enhanced capability for synthesis and modelling of complex systems in contrast to the classical phenomena of combinational state explosion when using finite state machine based methods.
Modular fault diagnosis based on discrete event systems for a mixer chemical process
2003
The knowledge of failure type and their location is an indispensable requirement for the establishment of tasks of adequate recovery strategies and maintenance of both factory automation and process control systems. The failure diagnosis methodology presented in the paper is based on discrete event systems models and on the diagnosers concept, those which permit the analysis off-line and online of diagnosability of failures that can occur in the processes. We present an approach for models and associated diagnosers based on a modular decomposition of the global system, with the purpose of avoiding the problems of the exponential explosion of the number of states and of the computational com…
Fault diagnosis with Coloured Petri Nets using Latent Nestling Method
2008
This paper presents a new methodology for permanent and intermittent fault diagnosis, named Faults Latent Nestling Method (FLNM), using Coloured Petri Nets (CPNs). CPNs and FLNM method allow for an enhanced capability for synthesis and modelling in contrast to the classical phenomena of combinational state explosion when using Finite State Machine based methods.
MARL-Ped: A multi-agent reinforcement learning based framework to simulate pedestrian groups
2014
Abstract Pedestrian simulation is complex because there are different levels of behavior modeling. At the lowest level, local interactions between agents occur; at the middle level, strategic and tactical behaviors appear like overtakings or route choices; and at the highest level path-planning is necessary. The agent-based pedestrian simulators either focus on a specific level (mainly in the lower one) or define strategies like the layered architectures to independently manage the different behavioral levels. In our Multi-Agent Reinforcement-Learning-based Pedestrian simulation framework (MARL-Ped) the situation is addressed as a whole. Each embodied agent uses a model-free Reinforcement L…
Evaluation of automatically steered agricultural vehicles
2008
The popularization of automatic guidance systems for off-road vehicles, especially in agricultural environments, has led to a sudden affluence of commercial solutions. As a consequence, end users are often overwhelmed by the spread of possibilities commercially available, on top of the confusion provoked by the guidance accuracy advertised by manufacturers. Therefore, there is a need for a methodology that objectively quantifies the level of performance of any auto-steering system, classifying different solutions according to their accuracy and reliability. This paper describes a method to evaluate the behavior of any automatically driven agricultural vehicle traveling along paths of any cu…
Vibration signature analysis for monitoring rotor broken bar in double squirrel cage induction motors based on wavelet analysis
2014
Purpose – The purpose of this paper is to present a diagnosis technique, for rotor broken bar in double cage induction motor, based on advanced use of wavelet transform analysis. The proposed technique is experimentally validated. Design/methodology/approach – The proposed approach is based on a combined use of frequency sliding and wavelet transform analysis, to isolate the contribution of the rotor fault components issued from vibration signals in a single frequency band. Findings – The proposed technique is reliable for tracking the rotor fault components over time-frequency domain. The quantitative analysis results based on this technique are the proof of its robustness. Research limit…
Land cover classification of VHR airborne images for citrus grove identification
2011
Abstract Managing land resources using remote sensing techniques is becoming a common practice. However, data analysis procedures should satisfy the high accuracy levels demanded by users (public or private companies and governments) in order to be extensively used. This paper presents a multi-stage classification scheme to update the citrus Geographical Information System (GIS) of the Comunidad Valenciana region (Spain). Spain is the first citrus fruit producer in Europe and the fourth in the world. In particular, citrus fruits represent 67% of the agricultural production in this region, with a total production of 4.24 million tons (campaign 2006–2007). The citrus GIS inventory, created in…
Leakage-detection in blade pitch control systems for wind turbines
2012
The main contribution of the work is a systematic study evaluating the performance of different filters for leakage detection in pitch control systems. The effectiveness of the proposed methods is examined in a Matlab/Simulink real-time environment. The test bed consists of the following elements: hydraulic power unit, servo valve, two leakage bypasses, hydraulic cylinder, payload and xPC-based control system. The filters are tested with the state-augmentation and the hypothesis testing approaches. To our knowledge, the comparison of these different approaches has not been done previously for this type of application. The paper concludes on the accuracy and sensitivity of the leakage detect…