Current Issue : October - December Volume : 2020 Issue Number : 4 Articles : 5 Articles
This paper focuses on the application of an active fault-tolerant control (AFTC) to a real nonlinear system using analytic redundancy\nin case of actuator faults.This approach is composed of the fault detection, isolation, and estimation (FDIE) module and\na control compensation module. A high-gain observer (HGO) is used for FDIE; a new control law is then reconstructed by the\naddition of the estimated actuator fault magnitude to the nominal control law. Experimental results highlight the performance of\nthe proposed approach when it is applied to the hydrographic plant...
In this analysis, we present results from measurements performed to determine the stability\nof a hand tracking system and the accuracy of the detected palm and fingerâ??s position. Measurements\nwere performed for the evaluation of the sensor for an application in an industrial robot-assisted\nassembly scenario. Humanâ??robot interaction is a relevant topic in collaborative robotics. Intuitive\nand straightforward control tools for robot navigation and program flow control are essential for\neffective utilisation in production scenarios without unnecessary slowdowns caused by the operator.\nFor the hand tracking and gesture-based control, it is necessary to know the sensorâ??s accuracy. For\ngesture recognition with a moving target, the sensor must provide stable tracking results. This paper\nevaluates the sensorâ??s real-world performance by measuring the localisation deviations of the hand\nbeing tracked as it moves in the workspace....
A coaxial dielectric barrier discharge plasma-assisted combustion actuator (DBD-PACA) system was set up to study its discharge\nand optical emission spectrum (OES) characteristics in space in this paper. Results showed that each discharge cycle can be divided\ninto four stages: a, b, c, and d. Discharge-on only occurred in stages b and d. Comparatively, the discharge intensity was larger in\nstage d due to the memory effect of excited electrons. Moreover, Lissajous figure and current-voltage methods were utilized to\ncalculate the power of the coaxial DBD-PACA, and both methods produced roughly similar results. The power presented an\nupward trend with increasing input voltage and airflow rate. In addition, numerous second positive system (SPS) excited nitrogen\nmolecules were detected from the OES signals. The intensity of the spectral lines (297.54 nm, 315.76 nm, 336.96 nm, and\n357.56 nm) first increased, then maintained, and then increased rapidly with the increased radius; however, the intensity of the\nspectral lines (380.34 nm, 405.80 nm, and 434.30 nm) basically remained unchanged, then increased, and finally decreased with\nthe increased radius. The vibrational temperature first decreased quickly and then increased and reached the minimum at....................
This paper presents the technology to control the shape of thin polymer doubly curved\nshell structures with a unimorph layer of strain actuators to achieve high quality, light-weight,\nfoldable space reflectors. The selected active material is PVDF-TrFE deposited by spin coating;\nit is electrostrictive, isotropic and enjoys an excellent piezoelectric coefficient d31...................
The ever increasing adoption of electrical power as secondary form of on-board power is\nleading to an increase in the usage of electromechanical actuators (EMAs). Thus, in order to maintain\nan acceptable level of safety and reliability, innovative prognostics and diagnostics methodologies\nare needed to prevent performance degradation and/or faults propagation. Furthermore, the use\nof effective prognostics methodologies carries several benefits, including improved maintenance\nschedule capability and relative cost decrease, better knowledge of systems health status and\nperformance estimation. In this work, a novel, real-time approach to EMAs prognostics is proposed.\nThe reconstructed back electromotive force (back-EMF), determined using a virtual sensor approach,\nis sampled and then used to train an artificial neural network (ANN) in order to evaluate the current\nsystem status and to detect possible coils partial shorts and rotor imbalances....
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