Search results for "VISION"
showing 10 items of 5066 documents
Allocation of actuators and sensors for coupled-adjacent-building vibration attenuation
2013
An actuator and sensor allocation approach is proposed for the design of coupled-adjacent-building vibration suppression under seismic excitation. This paper first establishes a full-order model of adjacent buildings with the location information of actuators and sensors. Then, the order of the model is reduced via modal cost analysis, by retaining the modes contributing the most. In view of the fact that the output powers of the actuators are limited, this paper brings forward a mixed H∞/GH2 control. By considering that not all the states of the system can be measured by the sensors, a dynamic output feedback controller is designed. The genetic algorithm is employed to obtain the locations…
Vibration analysis for bearing fault detection and classification using an intelligent filter
2014
Abstract This paper proposes an intelligent method based on artificial neural networks (ANNs) to detect bearing defects of induction motors. In this method, the vibration signal passes through removing non-bearing fault component (RNFC) filter, designed by neural networks, in order to remove its non-bearing fault components, and then enters the second neural network that uses pattern recognition techniques for fault classification. Four different categories include; healthy, inner race defect, outer race defect, and double holes in outer race are investigated. Compared to the regular fault detection methods that use frequency-domain features, the proposed method is based on analyzing time-d…
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…
Performance analysis of Alamouti coded OFDM systems over wideband MIMO car-to-car channels correlated in time and space
2014
In this paper, the performance of Alamouti coded orthogonal frequency division multiplexing (OFDM) systems over car-to-car (C2C) fading channels correlated in time and space is analyzed. Taking different geometrical scattering models into account, a generalized expression of the time-variant transfer function (TVTF) is derived for wideband multiple-input multiple-output (MIMO) C2C channels. We present a generalized expression for the bit error probability (BEP), which will be used to describe the performance of Alamouti coded OFDM systems over different types of C2C channel models, such as the rectangle model, the tunnel model, the street model, and the curve model. The effect of the maximu…
A novel visual pipework inspection system
2017
The interior visual inspection of pipelines in the nuclear industry is a safety critical activity conducted during outages to ensure the continued safe and reliable operation of plant. Typically, the video output by a manually deployed probe is viewed by an operator looking to identify and localize surface defects such as corrosion, erosion and pitting. However, it is very challenging to estimate the nature and extent of defects by viewing a large structure through a relatively small field of view. This work describes a new visual inspection system employing photogrammetry using a fisheye camera and a structured light system to map the internal geometry of pipelines by generating a photorea…
Low-cost underwater navigation systems by multi-pressure measurements and AHRS data
2017
This paper deals with accurate navigation for underwater remotely operated vehicles. A feasibility study for a multi-pressure device to be mounted on an ROV is presented. The device can provide accurate estimates of a ROV orientation and angular speed. It is based on the well-known total pressure principle, also used in a Pitot tube, and allows reconstruction of static and dynamic pressures, which in turn provide good estimates of the ROV's orientation and rotational speed, respectively. An appealing feature of the proposed device is its ability to provide accurate estimates even for low-speed movements.
Head and Body Coordination during Locomotion and Complex Movements
1994
Publisher Summary This chapter discusses theory in which it is argued that during complex movements, the head is stabilized intermittently under the control of gaze, and that this stabilization allows the head to serve as an inertial guidance platform for the control of multilimb movement. The otolithic organs, sacculus and utriculus, are inertial detectors of linear acceleration of the head in the plane of their macula. It is well established that in normal gravity conditions, although the perceived gravitational vertical deviates from the objective vertical by a few degrees, gravitational reference is used not only for posture but also for perceptual tasks that involve orientation in spac…
Integral display for non-static observers
2017
We propose to combine the Kinect and the Integral-Imaging technologies for the implementation of Integral Display. The Kinect device permits the determination, in real time, of (x,y,z) position of the observer relative to the monitor. Due to the active condition of its IR technology, the Kinect provides the observer position even in dark environments. On the other hand, SPOC 2.0 algorithm permits to calculate microimages adapted to the observer 3D position. The smart combination of these two concepts permits the implementation, for the first time we believe, of an Integral Display that provides the observer with color 3D images of real scenes that are viewed with full parallax and which are…
A new model for a safety analysis in a system of earthing systems interconnected through bare‐buried conductors
2009
PurposeThe purpose of this paper is to present a mathematical model for studying the effects of the interconnection through bare‐buried conductors (BBC) of the secondary substations' earthing system of an urban area.Design/methodology/approachThe developed methodology is based on three main points: the solution of the transmission lines' equations for the formulation of a lumped parameters model of a BBC considering the conductive effect; the division of the distribution network into simpler sub‐systems; and the calculation of all the voltages and currents of the medium voltage (MV) network and of the earthing systems using a multiport approach.FindingsThe methodology has been applied to va…
Remote programming of network robots within the UJI Industrial Robotics Telelaboratory: FPGA vision and SNRP network protocol
2009
This paper presents the UJI Industrial Robotics Telelaboratory, which lets Ph.D. and Master’s degree students perform robotics and computer vision tele-experiments. By using this system, students are able to program experiments remotely via the Web, in order to combine the use of a field-programmable gate array (FPGA) to provide real-time vision processing, a conveyor belt, and a Motoman industrial manipulator. This paper introduces the novel SNRP protocol (i.e., Simple Network Robot Protocol), which permits the integration of network robots and sensors within an e-learning platform in a simple and reliable manner. As long as the students are able to interact remotely with a real robotic sc…