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  • Optical Inspection of Mounted Printed Circuit Board using National Instruments Software
    1-6.
    Views:
    218

    The topic of the given task based on the optical opposition of a mounted printed circuit board using National Instruments software. During the inspection, 7 types of resistors, 3 types of integrated circuits, barcodes and text were detected. The results of the detection have been visualized and a Microsoft Excel scan report has been exported. The optical inspection was carried out using the National Instruments Vision Development Module and LabVIEW development environments.

  • The Optical Effect of Thermal Expansion over Excessed Injection Molded Lens Arrays in Modern LED Outdoor Luminaires
    1-4.
    Views:
    104

    For the rapid development observable in solid state lighting technology, both in favor of the better lighting performance achievable and the advantage in upkeep, changing the conventional installations to LED luminaires is often considerable in the modern roadway lighting practice. By these modernization investments the sales volume is usually high for lower additional expenses and a quicker RoI; thus the replacement products are generally cost sensitive. As the global market price of Aluminum increases on a long term trend, while the cost of the task efficient luminous power became very desirable with Light Emitting Diode; a high level of integration and compactness is demanded by such luminaire designs. This approach raises complex technical challenges, as the thermal expansion difference between the lens array and the Insulated Metal Substrate (IMS) Printed Circuit Board can lead to major deviation in the light distribution over the rated ambient temperature range. Having a robust design is a key aspect in providing a reliable, safe lighting design for any application of a global product.

  • Time Domain Analysis and Spectral Methods for Determining Rotational Speed of Rotary Machines
    1-8.
    Views:
    123

    Accurate estimation of rotational speed of rotary machines has usually high priority in technical applications. This information should be calculated for many diagnostic algorithms, control or regulation processes. Incorrectly estimated values could occur serious disturbances in the operation of machines. Additional instrumentation often may be obstructed due to lack of space, but the construct of the machine may also affect the accuracy of measurement. In such cases, vibration diagnostic tools can be the disposal of difficulty. Mounting an acceleration sensor onto the outer surface of the measured device is not a major challenge. In most cases using time, frequency or quefrency domain analysis, it is possible to estimate the rotational speed of the analysed rotary machine. The calculated spectra and cepstra can help to determine the rotational speed more easily and more accurate than the time domain methods. This paper presents the comparison of these methods in terms of their usability and rotational speed estimation accuracy. A possible error of traditional optical measurement due to misalignment and benefits of the other methods are illustrated in this article via measured data series of a Brushless DC (BLDC) motor driven system.

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