scholarly journals Design and Experimental Evaluation of a Form Trimming Machine for Horticultural Plants

2021 ◽  
Vol 11 (5) ◽  
pp. 2230
Author(s):  
Mao Li ◽  
Lina Ma ◽  
Wangyuan Zong ◽  
Chengming Luo ◽  
Muchang Huang ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
Labor Input ◽  
Rotating Speed ◽  
Evaluation Indexes ◽  
Time Consumption ◽  
Cutting Frequency ◽  
Human Labor ◽  
Horticultural Plants ◽  
Working Parameters ◽  
Supporting Frame

Form trimming is an important practice in horticulture. Currently, handheld trimming tools are the most commonly used in China, which presents certain disadvantages including high human labor input, low productivity and inconsistent performance. In this work, a wheeled form trimming machine was designed for shrub plants with the aim of reducing labor input, increasing efficiency and improving trimming performance. The machine was mainly composed of three parts: a supporting frame, a rotary base and a knife system. The design and construction of the key components of the machine were introduced. The knife system was a combination of multiple cutter units with reciprocating motions. The number of units and their connecting angles could be adjusted to realize different trimming shapes. The knife system was carried by the rotary base and could realize 360° rotations to cut the plants into a desired form. Experiments were performed to determine the optimal working parameters (cutting frequency of the cutter unit and rotating speed of the rotary base). The similarity between the plant profile after trimming and the profile of the knife system and the consumed time in each operation were chosen as two evaluation indexes. Results showed that when the cutting frequency was 16.7 Hz and the rotating speed of the rotary base was 13.5 r/min, the trimming operation could be completed by two circles, and the time consumption was 8.89 s. Furthermore, to test the adaptability of the machine, five different shrub plants were chosen and trimmed by the machine, and results showed that the overall similarity was above 93%. Therefore, the form trimming machine developed could meet the requirements of shrub trimming in horticulture with desirable precision and adaptability.

Design and Testing of a Shearing and Breaking Device for Mulch Film and Cotton Stalk Mixtures

2021 ◽  
Vol 64 (2) ◽  
pp. 545-555
Author(s):  
Feng Pan ◽  
Bin Hu ◽  
Xin Luo ◽  
Mengyu Guo ◽  
Haomeng He
Keyword(s):  
Parameter Optimization ◽  
Shear Fracture ◽  
Three Dimensional ◽  
Technical Solution ◽  
List Type ◽  
Test Results ◽  
Evaluation Indexes ◽  
Mulch Film ◽  
Working Parameters ◽  
Shearing Mechanism

HighlightsThis article presents a shearing and breaking device for mulch film and stalk mixtures after mechanized recovery.The focus is on a curved V-shaped mechanism with three-dimensional precompression and shearing functions.The device can efficiently and continuously perform film crushing, stalk crushing, and entanglement breaking.The crushed film and stalk mixture is conducive to material separation, further treatment, and recycling.Abstract. Because the mixture of mulch film and stalks collected in harvested cotton fields in Xinjiang, China, cannot be separated mechanically, a technical solution for shearing and breaking is proposed. This study designed a shearing and breaking device for film and stalk mixtures that can continuously perform film crushing, stalk crushing, and entanglement breaking. The design focuses on a curved V-shaped shearing mechanism, which provides three-dimensional shearing and improves the crushing of film and stalks. The linear speed of the conveying rollers (x1), the working angle of the shearer (x2), and the speed of the shearer spindle (x3) were selected as influencing factors, and the crushed film rate (Ph), crushed stalk rate (Gh), and broken entanglement rate (Kh) were used as evaluation indexes in quadratic orthogonal rotation combination tests. The test results were analyzed with Design-Expert software, and a regression model between each factor and the evaluation indexes was established to analyze the significance of each factor’s influence. The results showed that the influences of the three factors on Ph in descending order were x3, x2, and x1. The order of influence on Gh and Kh was x3, x1, and x2. The optimization module in the software was used for parameter optimization, and the optimal combination of working parameters of the device was x1 = 0.98 m s-1, x2 = 153°, and x3 = 753 r min-1. The optimized parameter combination was tested and verified, and the results were Ph = 77.28%, Gh = 87.78%, and Kh = 85.30%. The test results are basically consistent with the predicted values, and the optimized working parameters are reliable and can meet the requirements for the shear fracture of film and stalk mixtures. This research provides a technical reference for the cutting and crushing of complex mixed solid materials. Keywords: Agricultural machinery, Curved V-shaped moving knife, Design, Film and stalk mixture, Parameter optimization.

Design and Experimental Study of a Spiral Auxiliary Feeding Device for Lodged Corn on a Combine Harvester

2021 ◽  
Vol 65 (1) ◽  
pp. 31-38
Author(s):  
Qiankun Fu ◽  
Jun Fu ◽  
Zhi Chen ◽  
Rongqiang Zhao ◽  
Luquan Ren
Keyword(s):  
Orthogonal Experiment ◽  
Optimal Harvesting ◽  
List Type ◽  
Forward Speed ◽  
Factors Affecting ◽  
Rotating Speed ◽  
Combine Harvester ◽  
Mechanical Bending ◽  
Working Parameters ◽  
Grain Security

HighlightsThis study designed an auxiliary feeding device for lodged corn on a combine harvester.The mechanical characteristics of lodged corn stalks were studied as the basis of the design.The working parameters were optimized in an orthogonal experiment.Abstract. Lodging causes kernel and ear loss in mechanical harvesting of corn and threatens grain security. To address this issue, the mechanical bending properties and lifting forces of lodged corn stalks were explored in this study. The ears of lodged corn could be lifted to the normal harvesting height by applying an upward force to the stalks. Based on this conclusion, an auxiliary feeding device for lodged corn in a combine harvester was designed. An orthogonal optimization experiment was conducted to explore the effects of working parameters on the device performance. The results demonstrated that the sequence of the factors affecting kernel loss with the auxiliary feeding device was: harvesting direction, forward speed of the harvester, and rotating speed of the spiral stalk lifter. The optimal combination of harvester forward speed and rotating speed of the spiral stalk lifter was 0.5 m s-1 and 300 rpm, and the ratio of the peripheral speed to the speed of motion was 9.42. The optimal harvesting direction was opposite to the lodging direction of the stalks. This study provides a theoretical basis and design reference for low-loss harvesting of lodged corn. Keywords: Auxiliary feeding, Combine harvester, Corn, Harvest loss, Lodging, Orthogonal experiment.

scholarly journals Consideration and analysis for attachment position of supernumerary robotic limbs

2021 ◽  
Author(s):  
ziyu liao ◽  
baichen
Keyword(s):  
Experimental Evaluation ◽  
Design Parameter ◽  
Simulation Experiment ◽  
Wearable Robot ◽  
Evaluation Indexes ◽  
Multiple Tasks ◽  
New Type ◽  
Design Factors

Abstract The supernumerary robotic limbs(SRLs) is a new type of wearable robot that assists the operator with additional robotic limbs and allows the operator to perform multiple tasks simultaneously. Due to the SRLs having various combinations of robotic limb and attachment positions, and there is an insufficient discussion on the influence of different wear positions on the SRLs. Therefore, this paper improved the evaluation indexes from previous studies and presents an experimental evaluation of the performance of indexes between humans and SRLs. This paper analyzed the 5 different positions based on the improved evaluation indexes, 2 optimal positions are found with the simulation experiment. Then the two design factors to improve the performance of evaluation indexes are discussed. The evaluation indexes can be utilized as a design parameter for evaluating human-robot interactions of SRLs.

scholarly journals Effect of Airflow Field in the Tangential-Longitudinal Flow Threshing and Cleaning System on Harvesting Performance

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Taibai Xu ◽  
Yaoming Li
Keyword(s):  
Flow Field ◽  
Working Conditions ◽  
Air Flow ◽  
Internal Space ◽  
Air Velocity ◽  
Rotating Speed ◽  
Cleaning System ◽  
Cleaning Device ◽  
Combine Harvester ◽  
Working Parameters

The threshing and cleaning device in the grain combine harvester is located in the same airtight space, and the air flow field in it should also be studied and tested as a whole system. In order to study the distribution of air flow field and the influence of working parameters on the air flow field in the internal space of threshing and cleaning system, the method of predicting harvest performance indexes (grain loss rate and grain impurity rate) by air flow field analysis was explored. First of all, taking the longitudinal grain combine harvester of our research group as the test object and taking the rotating speed of centrifugal fan, the angle of fan plate, the opening of chaffer, and the rotating speed of threshing cylinder as the research factors, the internal space flow channel model of threshing and cleaning system under different working conditions was established and CFD software was used to simulate and analyze the air flow field. At the same time, the hot wire anemometer is used to measure and verify the distribution of air flow field in the threshing and cleaning system under various working conditions. Then, the harvest performance index of the threshing and cleaning system under the rated feeding rate is tested under the corresponding working conditions to find the relationship between the distribution of air flow field and harvest performance, put forward the corresponding analysis and prediction methods, and establish the mathematical relationship model between the simulated air flow field and harvest performance index. The results of simulation and experiment show that the average air velocity can more accurately reflect the cleaning performance. The mathematical function of the relation curve is Y = 11.71X − 4.76, and the prediction error is within 9.4%. The air velocity in the middle area of the vibrating screen is approximately in proportion to the cleaning performance, which provides the theoretical and experimental basis for the design of the threshing and cleaning device and the adjustment of the working parameters in the field harvest. In addition, it can save the design time and cost and reduce the seasonal impact of field experiment.

Analysis of Elastohydrodynamic Lubrication of Ball Screw with Rotating Nut

2011 ◽  
Vol 121-126 ◽  
pp. 3132-3139 ◽  
Author(s):  
Shi Gang Mu ◽  
Xian Ying Feng
Keyword(s):  
Angular Velocity ◽  
Film Thickness ◽  
Elastohydrodynamic Lubrication ◽  
The Other ◽  
Ball Screw ◽  
Rotating Speed ◽  
Lubricant Oil ◽  
Pressure Spike ◽  
Elliptical Contact ◽  
Working Parameters

The isothermal elliptical contact elastohydrodynamic lubrication (EHL) problem in ball screw with rotating nut was studied.Numerical solution to the problem was obtained for various parameters with a multigrid solver.Based on work mentioned above,the influence of the working parameters such as the rotating speed of screw shaft and the contact force,on the lubricant oil film thickness and pressure is analyzed .The results showed that, with the increasing loads,the pressure became higher,the film thickness became smaller. On the other hand,when the angular velocity was higher,the film thickness was higher, while the pressure spike was closer to the center of the contact. Because of the spinning, the slide-roll ratio was not a constant.

A light optical diffractometer for electron microscopical images operating in line

1978 ◽  
Vol 36 (1) ◽  
pp. 86-87
Author(s):  
P. Bonhomme ◽  
A. Beorchia
Keyword(s):  
Electron Microscopy ◽  
Electron Transfer ◽  
Electron Microscope ◽  
Image Converter ◽  
Coherent Light ◽  
Spatial Filters ◽  
Electron Image ◽  
Electron Microscopical ◽  
Working Parameters ◽  
Amorphous Part

We have already described (1.2.3) a device using a pockel's effect light valve as a microscopical electron image converter. This converter can be read out with incoherent or coherent light. In the last case we can set in line with the converter an optical diffractometer. Now, electron microscopy developments have pointed out different advantages of diffractometry. Indeed diffractogram of an image of a thin amorphous part of a specimen gives information about electron transfer function and a single look at a diffractogram informs on focus, drift, residual astigmatism, and after standardizing, on periods resolved (4.5.6). These informations are obvious from diffractogram but are usualy obtained from a micrograph, so that a correction of electron microscope parameters cannot be realized before recording the micrograph. Diffractometer allows also processing of images by setting spatial filters in diffractogram plane (7) or by reconstruction of Fraunhofer image (8). Using Electrotitus read out with coherent light and fitted to a diffractometer; all these possibilities may be realized in pseudoreal time, so that working parameters may be optimally adjusted before recording a micrograph or before processing an image.

Age 60 rule research: IV. Experimental evaluation of pilot performance.

1994 ◽  
Author(s):  
D. T. Hyland ◽  
E. J. Kay ◽  
J. D. Deimler
Keyword(s):  
Experimental Evaluation ◽  
Pilot Performance

The experimental evaluation of supervisory training

1970 ◽  
Author(s):  
Marc J. Wallace ◽  
William Weitzel
Keyword(s):  
Experimental Evaluation ◽  
Supervisory Training

Experimental Evaluation of the Dermoskeleton Concept: Addressing the Soldiers Overload Challenge

2012 ◽  
Author(s):  
Chris Ste-Croix ◽  
David Tack ◽  
Denis Boucher ◽  
Francois Ruel ◽  
Gilles Pageau ◽  
...  
Keyword(s):  
Experimental Evaluation
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