Tag Archives: vibration

1165-1192 V. Bulgakov, V. Adamchuk, M. Arak and J. Olt
Theory of vibration-assisted sugar beet root lifting
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Theory of vibration-assisted sugar beet root lifting

V. Bulgakov¹, V. Adamchuk², M. Arak³ and J. Olt³⋅*

¹National University of Life and Environmental Sciences of Ukraine 15, Heroyiv Oborony Str., UK03041 Kyiv, Ukraine
²National Scientific Centre, Institute for Agricultural Engineering and Electrification, 11, Vokzalna Str., Glevaкha-1, Vasylkiv District, Kiev Region, UK08631, Ukraine
³Estonian University of Life Sciences, Institute of Technology, 56 Kreutzwaldi Str., EE51014 Tartu, Estonia;
*Correspondence: jyri.olt@emu.ee

Abstract:

The vibration-assisted lifting of sugar beet roots from the soil has been gaining increasingly wide use worldwide and the majority of sugar beet harvesting machinery manufacturers produce beet harvesters equipped with just such kind of lifting units. In such units the priorities are low tractive resistance, the high quality of harvesting in terms of undamaged side surfaces of beet root bodies and intact tail parts as well as the high degree of their initial cleaning from the stuck soil. However, the parameters of the oscillatory processes generated by the vibrational lifting units used on the majority of sugar beet harvesting machinery in the market have rather average values appropriate for relatively favourable harvesting conditions (soft loose soil, beet root sizes close to the average, properly lined up planting rows etc.). But when the harvesting conditions deviate from their favourable values (especially in case of dry and strong soil), the vibrating lifters start performing the digging process with significant damage to the beet roots (breaking and tearing off the tail parts), their power consumption rises excessively sharply, the unit vibration drives prove to be unreliable. The literature source analysis has shown that any sufficiently detailed, comprehensive and dependable theory of direct beet root lifting from the soil is virtually absent. Thus, the aim of this research study has been to work out such a theoretical basis for the process of vibration-assisted beet root lifting, which will allow to calculate, in accordance with the harvesting parameters, the optimal design and kinematic parameters of the process ensuring the high quality of harvesting. A new theory has been developed, which describes the process of direct vibration-assisted beet root lifting performed under the effect of the vertical disturbing force and the pulling force, imparted to the root by the lifting unit. The obtained system of differential equations has made it possible to establish the law of motion of the beet root in the process of its direct vibration-assisted lifting and perform PC-based numerical calculations, which provide the basis for determining optimal kinematic modes of operation and design parameters of vibrational lifting units subject to the condition of maintaining sugar beet roots intact when harvesting them.

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251-260 P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle
Vibration and noise caused by lawn maintenance machines in association with risk to healt
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Vibration and noise caused by lawn maintenance machines in association with risk to healt

P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle

Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia;

Abstract:

The aim of this study was to compare vibration and noise characteristics caused by different types of lawn maintenance machines in association with the risk factors to workers’ health. In the present study, the method connecting vibration hazard, health damages and risk levels is presented. Three types of agriculture machines were investigated: all-terrain vehicles (ATV), simple lawn-mowers, ride-on mowers. These machines are used not only in occupational settings, but also by the inhabitants for cutting grass. The gardeners and maintenance workers of the municipal authorities use them daily, sometimes 8 hours a day. The protective equipment against noise is used in occupational settings, but hardly by the public. Noise was evaluated using a Sound Level Meter (TES 1358) following the standard ISO 9612:2009. Vibration was determined as acceleration, velocity and amplitude – measured using a Vibration Dosimeter & Analyser (SV 100) following the standards ISO 2631-4, EVS-EN 5349-2. The risk to the health is assessed by the original flexible risk assessment method worked out in TTU. On the basis of this flexible model the scheme for connecting the local and whole-body vibration hazards and possible health damages was worked out. The results showed that there are differences in the noise and vibration generated by the ATV, lawn-mowers and ride-on mowers. The safest was ride-on mower (local vibration below 1.15 m (s2 ) -1). Lawnmowers gave high vibration levels (over 3 m (s2 ) -1). The personal protective equipment (PPE) has to be worn by all users of the investigated machines. The noise spectral content by these three types of machines is presented and it is different. This enables to choose the right type of ear-muffs by the frequency of noise. The PPE against vibration is also available.

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