INMATEH - Agricultural Engineering

6

Authors: Veringă D., Vintilă M., Popa L., Ştefan V., Petcu A.S.

The paper presents the Golden Delicious apples experimental researches, that aimed to emphasize apples behaviour at mechanical static or quasi-static compression stress and mechanical and rheological characteristics of fruits correlated to deficiencies determined (contusions, form distorsion), in order to anticipate their conduct in different practical situations.

6

Authors: Sokil M.B., Lyashuk O.L., Dovbush А.Р.

The developed technique makes possible to investigate the impact on oscillations of flexible elements of drive systems and transportation of nonlinear forces, the speed of longitudinal movement and perturbations of boundary conditions. Based on the obtained results it is proved that even for the linear analogue system the slowly time-dependent variable of the distance between the flexible elements (SE) contact points and the pulleys causes the change of the basic parameters of the waves. The limits of applying the wave theory of motion in the case of nonlinear oscillations of flexible elements of drive systems under slowly varying boundary conditions are expanded. The basic computations to analyze the main parameters of the dynamic process depending on motion speed of flexible element, tension force, and the ratio describing the motion principle of the contact point of flexible element and the pulley, are made.

8

Authors: Shvedyk M.

In the article the studies of crop losses causes during harvest are presented. It is established that a significant cause of grain loss is a non-simultaneous ripening in the wheat. Thus, during reel bats impacts on stalks, the largest and most valuable grains that ripen earliest are knocked out of the wheat and fall to the ground. It is established that these losses are significant and irreversible. The current technical condition of combine harvesters cannot eliminate these losses. To eliminate these losses, a new design of pneumatic collector has been proposed in the article. The principle of its work is based on the vacuum created. Due to the vacuum, the grains that were knocked out from the wheat by reel bats are sucked and sent into the cyclone.

8

Authors: Hevko Iv.B., Lyashuk O.L., Leshchuk R.Y., Rogatinska L.R., Melnychuk A.L.

Method of calculation of radius of bending for the flexible screw sectional conveyer was presented. Analytical dependencies for finding maximal turning radius in order to provide the reliable operation of the mechanism were defined. The stand construction for investigation of the angle of twist of the sectional operating members was developed. The effect of different construction parameters (section length, diameter) on their operating life characteristics as well as the comparative testing of different types screw operating elements (SOЕ) samples, were found. The technique of testing the working bodies of flexible screw conveyor sections for manufacturability of a construction, which provides a minimum bend radius of track transportation, was presented.

8

Authors: Yue Hongwei, Cai Ken, Lin Hanhui, Chen Zhihui, Zeng Zhaofeng

With the wide application of machine-vision technology in detecting agricultural plant diseases and insect pests in the field, this paper proposed an innovative approach for performing automatic segmentation of rice planthopper images. First, to weaken background interference, the Otsu approach was adopted to accomplish the preliminary segmentation. Then, a steerable filter was employed to improve the segmentation results of the feet and tentacles. Finally, by adding priori gray-level information, our proposed method improved the approximation capability of level-set-based evolution curves to targets. Results indicated that the approach adopted in this paper could clearly segment the contour of rice planthoppers.

10

Authors: Tverdokhlib I.V., Spirin A.V.

The article describes the technological process of operation of the improved disc grating apparatus aimed to grate seed of legume grasses and presents the results of analytical studies of its performance.

10

Authors: Wenhua Jia, Chenbo Yin, Binghui Jia , Guo Li, Dasheng Zhu, Song Zhang

To cope with the increasingly severe working environment confronting agricultural load tractors, load tractor design must consider the comprehensive influences of noise immunity, control precision, and power loss, among others, of hydraulic systems. A SY235 load tractor and a dual-spool multi-way valve-based prototype were applied as research objects in this research. The antisymmetric data processing function of AMESIM software was employed to update and replenish point data, while a cubic interpolation method was adopted to process the data. In addition, the displacement characteristics, inlet and outlet pressures, and energy consumption of each cylinder in the hydraulic systems of both load tractors equipped respectively with the dual-spool multi-way valve and single-spool multi-way valve were investigated. Meanwhile, a single action experiment was performed on the booms, bucket rods, and buckets of the two load tractors. A comparison of the real test with the simulation model demonstrated that the cylinder controlled by the dual-spool valve exhibited small pressure and power consumption and quick displacement response. Therefore, the cylinders controlled by the dual-spool multi-way valve system had quicker pressure response, smaller pressure and overshoot, and superior overall manipulability. Finally, retraction and external swinging experiments of the buckets were performed on the dual-spool experimental prototype. Experimental results demonstrated that the dual-spool multi-way valve system exhibited faster displacement response and more superior overall performance compared with the single-spool control system. The simulation model combined with the real vehicle experiment is of great significance to the further study of the static and dynamic characteristics and energy-saving performance of the dual-spool agricultural load tractor.