113 research outputs found

    Evaluation of passive cooling system in plywood enclosure for agricultural robot prototype

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    Received: February 1st, 2021 ; Accepted: March 27th, 2021 ; Published: April 29th, 2021 ; Correspondence: [email protected] use of autonomous robots in agriculture has been increasing rapidly in recent years, but is hampered by the complexity of data recording and processing. The prototyping process involves many changes to the housing design during development. Using laser cutting to make a housing is more convenient, faster and cheaper than milling or casting if only one body needs to be made. To speed up the production of autonomous robot prototypes, the body was made of birch plywood using laser-cut parts. The study analyses the efficiency of passive cooling to make sure that birch wood plywood is suitable for the production of a robotic body for outdoor use in agriculture. Under laboratory conditions, temperature measurements were made inside and outside the housing to determine how the heat released by the electronic components dissipates into the environment. An exponential model with a static coefficient and a time constant can be used to determine the recommended operating time at different ambient temperatures when the allowable operating temperature of the component is known. Air flow and heat transfer simulations were performed to represent heat dissipation. Birch plywood can be used for the production of prototype enclosures for agricultural robots, but the design must provide technological solutions for heat dissipation to prevent overheating of electronic components

    Experimental efficiency evaluation of 445 nm semiconductor laser for robotized weed control applications

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    Robotized weed control is one of perspective approaches for decreasing ecological impact of farming. Although current level of technology development allows robotized weed control to be economically reasonable only in specific applications, it is only a matter of time to introduce them in full-scale industrial farming. In general terms weed control using agricultural robots consist of two parts: recognition and spatial localization of weeds (distinguishing them from crops) and precision application of some kind of growth limiting activity. Recognition and localization is usually carried out using computer vision solutions (image filtering and transformations, artificial neural networks etc.). Growth limiting in its turn is performed by mechanical, precise chemical, thermal, cryogenic or other means. This article covers application of laser radiation for thermal destruction of unwanted plant canopies. In most cases CO2 type lasers with 10.6 µm wavelength is used as they are affordable and they are applicable to use with plant biomass due to their spectral characteristics. Drawbacks of CO2 lasers are low efficiency, size, weight and complex maintenance. In recent years relatively powerful short-wavelength semiconductor lasers have became broadly available on market. Light absorption of healthy green leaves is much better in blue-UV spectrum than in green, far infrared and near infrared, which is almost completely reflected by leaves. Thus an experimental study of using 12 W output 445 nm blue semiconductor laser for weed canopy cutting was carried out. The experiments were performed with direct laser radiation, the laser module was positioned using robotic manipulator with different speeds and cutting patterns

    Examining vortex-induced vibration through convolutional neural networks

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    This research is supported by the projects GA21-31457S ”Fast flow-field prediction using deep neural networks for solving fluid-structure interaction problems”

    Characterization of a front-end electronics for the monitoring and control of hadrontherapy beams

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    Abstract An integrated 64-channel device for the read-out of parallel plate pixel and strip ionization detectors has been developed by the INFN and University of Torino. The detectors will be used for the monitoring and control of hadrontherapy beams. The ASIC has been designed in CMOS 0.8 μm technology and it is based on a current-to-frequency converter followed by a synchronous counter. In this paper, we present a detailed characterization of the device done with 113 chips

    'Ionizing radiation effects on a 64-channel charge measurement ASIC designed in CMOS 0.35 μm technology'

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    A 64-channel circuit Application Specific Integrated Circuit (ASIC) for charge measurement has been designed in CMOS 0.35mm technology and characterized with electrical tests. The ASIC has been conceived to be used as a front-end for dosimetry and beam monitoring detector read-out. For that application, the circuitry is housed at a few centimeters from the irradiated area of the detectors and therefore radiation damages can affect the chip performances. The ASIC has been tested on an X-ray beam. In this paper, the results of the test and an estimate of the expected lifetime of the ASIC in a standard radio-therapeutical treatment environment are presented. An increase of the background current of 2 fA/Gy has been observed at low doses, whilst the gain changes by less than 3% when irradiated up to 15 kGy. Furthermore it has been assessed that, when used as an on-line beam monitor and the annealing effect has been taken into account, the background current increase is � 440 fA/year
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