Vibrations are dynamic phenomena occurring in elastic or quasi-elastic media after a local excitation and becoming manifested by propagating the excitation within the medium in the form of some elastic oscillations. Thus, depending on the phenomenon dynamics, there can be met vibrations with low variation frequencies, characteristic to the mechanical structures, structures in constructions and earthquake waves, as well as vibrations with high variation frequencies. The vibration measuring is performed on a straw cereal harvesting machine with an axial threshing apparatus ("CASE IH") in two conditions: in a stationary position and during work, by using transducers for each of the main working parts of the harvester: thresher, header (stripper), chassis and operator's chair. On the basis of the values of longitudinal, cross and vertical accelerations, measured at various frequencies in the two operating conditions of the harvester (at stationary and during work), the effect of the vibrations is established on each of these parts and, finally, cumulated, the vibrations sent to the operator's chair, the nomograms following to be traced and to be established the range with the limits up to which these are not dangerous for the operator's health.

This article represents research regarding use of pneumatic linear actuator.  A pneumatic linear drive is a device that creates motion in a straight line. The linear drive with solenoid in this manuscript is a pneumatic actuator. The pneumatic linear drive works only with  compressed air. Compressed air usually has a pressure of between 2·105 Pa and 6·105 Pa. Linear drive with solenoid can be used for various applications, including pulling/pushing, pick-and-place applications or lifting/moving.  After Introduction, the authors study two pneumatic circuits using linear drive with solenoid coupling. In fact, the first pneumatic scheme in this paper has only one device (linear drive 1-1). But, the second pneumatic circuit has two actuators (linear drives 2-1 and 2-2). Further on, the authors present two electro-pneumatic circuits. In any case, a simple  electro-pneumatic circuit that has a linear drive with solenoid coupling. Moreover, the second electro-pneumatic system has a linear drive with solenoid coupling and PLC (Programmable Logic Controller). The pneumatic and electro-pneumatic circuits given in this manuscript are made using FluidSim software from Festo.

In order to be used as food supplements, materials (medicinal and aromatic plants, other materials containing active principles, etc.) need to be chopped and sorted by size, depending on the field of use: herbal tea, suspensions, tinctures, etc. The paper presents the results of research on the sorting process of some materials containing active principles (yarrow, alfalfa and willow bark) using a sorting machine provided with 2 electro vibrators fitted on each side of the framework within which 3 sieves with a mesh size of: 2.15, 4 and 8 mm are fitted, changing the oscillation regime of the sieves by adjusting the angle of the electro vibrators, in order to identify the optimal sorting regime.

The efficiency of the technological operations executed by robots depends on how their kinematic parameters were calculated. This paper presents the exactly calculus of the robots kinematics parameters. As the algorithm has a substantial number of operations, it is necessary to use the computer.

The mechanical sorting process of granular and vegetal materials is a complex technological process influenced by a series of factors from which we remind: mechanical vibratory motion, geometrical measures of the sorting equipment and technological factors. Based on correlations between the presented elements one can establish the technological parameters of the sorting process so that to realize a quality separation.In the paper we present a method for determination of mechanical oscillations influence on the quality of the sorting process with planar sieves. The experiments performed on a dimensional sorter with planar sieves aimed at identification of an optimum working set-up in terms of frequency and amplitude of the sorter’s vibrators, for a quality separation degree.