Tag Archives: accuracy

502-518 V. Bulgakov, J. Olt, S. Pascuzzi, S. Ivanovs, V. Kuvachоv, F. Santoro, Ia. Gadzalo, V. Adamchuk and M. Arak
Study of the controlled motion process of an agricultural wide span vehicle fitted with an automatic driving device
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Study of the controlled motion process of an agricultural wide span vehicle fitted with an automatic driving device

V. Bulgakov¹, J. Olt²*, S. Pascuzzi³, S. Ivanovs⁴, V. Kuvachоv⁵, F. Santoro³, Ia. Gadzalo⁶, V. Adamchuk⁷ and M. Arak²

¹National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony Str., Kyiv UA03041, Ukraine
²Estonian University of Life Sciences, Institute of Forestry and Engineering, 56 Kreutzwaldi Str., Tartu EE51006, Estonia
³University of Bari Aldo Moro, Department of Agricultural and Environmental Science, Via Amendola, 165/A, IT70125 Bari, Italy
⁴Latvia University of Life Sciences and Technologies, Cakstes Blvd. 5, LV3001 Jelgava, Latvia
⁵Dmytro Motornyi Tavria State Agrotechnological University, 18B Khmelnytsky Ave, UA72310, Melitopol, Zaporozhye Region, Ukraine
⁶National Academy of Agrarian Sciences of Ukraine, 9 Mykhailo Omelyanovych-Pavlenko Str., UA01010, Kyiv, Ukraine
⁷Institute of Mechanics and Automation of Agricultural Production of the National Academy of Agrarian Sciences of Ukraine, 11 Vokzalna Str., Glevakha stl, Vasylkivsky Dist., UA08631, Kyiv Region, Ukraine
*Correspondence: jyri.olt@emu.ee

Abstract:

The aim of research is to analyse the process of the wide span vehicle motion on the treads of the permanent process track with the use of the traction method of turn. The completed studies have proved that the plane-parallel motion of a wide span vehicle solely with the use of the traction method of turn on the treads of the permanent process track requires a significantly smaller difference between the moments applied to the wheels on the right side and on the left side of the vehicle, as compared to that of a crawler tractor. This difference is in proportion to the width of its wheel base that has a relatively smaller length. It has been established that the use of solely traction-based turn does not provide for the adjustment of the motion trajectory through the lateral (plane-parallel) displacement of the fore-and-aft axis of the agricultural wide span vehicle. The oscillations in the lateral displacement of the agricultural wide span vehicle in the process of its motion are low-frequency ones. The main variance spectrum of these oscillations is concentrated within the range of frequencies of 0–2 s−1. At the same time, the maximum transverse displacement of the agricultural wide span vehicle equal to 1.3 10−5 m N−1, occurs also at low frequencies. In view of the fact that the main variance spectrum of the oscillations of the tangential forces applied to the wheels on the left and right sides of the agricultural wide span vehicle is concentrated exactly within a low frequency range, only the high accuracy of the system using a laser beam can ensure its satisfactory steerability.

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1688–1704 P. Matějka, J. Kadeřábek and V. Shapoval
Measurement Robotic Arm (MRA) for the evaluation of localization sensors properties
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Measurement Robotic Arm (MRA) for the evaluation of localization sensors properties

P. Matějka¹*, J. Kadeřábek² and V. Shapoval²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ16500 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Agricultural Machines, Kamýcká 129, CZ16500 Prague, Czech Republic
*Correspondence: matejkapavel@tf.czu.cz

Abstract:

The purpose of this longitudinal project is to verify the dynamic properties of the Real Time Kinematic receivers (‘RTK’). For this purpose, a verification method using Measurement Robotic Arm (‘MRA’) described in this paper has been developed. This device can be moved along a circular trajectory in a horizontal surface. Using the methodology described in this paper, the absolute position of the MRA trolley in absolute time can be defined with absolute accuracy and can serve as a reference for the verification of RTK receivers positioning. Its movement, including its breaking, can be controlled via a PC app and various sensor properties can be monitored. The position of the trolley is determined by the encoder. A Hall sensor indicates the absolute start position of one full turn. The absolute time marks of the measurement and the time synchronization of the microprocessor based on Pulse Per Second (‘PPS’) were obtained from the standard GNNS receiver. This study provides information about a proposal solution of the MRA reference system in terms of the frame construction description, the design of electronic equipment and the design of a software solution for processing and logging of messages. This paper also presents the results of three tests performed to verify the functionality and reliability of the MRA system: PPS time accuracy verification, the quantity and correctness of sent messages according to the arm instantaneous speed, and a real RTK verification test. The MRA also can be used to verify the dynamic properties of other localization devices.

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749-757 J. Kadeřábek, V. Shapoval and P. Matějka
Evaluation of the RTK receiver’s capability of determination the accurate position
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Evaluation of the RTK receiver’s capability of determination the accurate position

J. Kadeřábek¹*, V. Shapoval¹ and P. Matějka²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Agricultural Machines, Kamýcká 129, CZ16500 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ16500 Prague, Czech Republic
*Correspondence: jkaderabek@tf.czu.cz

Abstract:

The main aim of this experiment was to compare low-cost RTK receiver, that possible can be used for precise agricultural application, another that is currently used for these applications and the third one that suits for static measurement the most and gives the reference point for results comparison. The main idea of this research was to compare the measured positions during static measurement of RTK receivers. Were discovered that the receiver Trimble 750 was not able to work in fix mode (mode when the RTK receivers are capable to measure the most accurately) for the whole time. This fact affects the results from whole measurement and showed that errors were a little higher than producers specifies. The low-cost receiver u-Blox C94-M8P showed satisfying results when in most cases it was capable to solve the problem of ambiguity integer phases. The main parameters in this work that were counted and summarized were: accuracy, precision, RMS error, system status ratio and number of satellites.

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