Applications of Discrete Element Method in the Research of Agricultural Machinery: A Review

As a promising and convenient numerical calculation approach, the discrete element method (DEM) has been increasingly adopted in the research of agricultural machinery. DEM is capable of monitoring and recording the dynamic and mechanical behavior of agricultural materials in the operational process of agricultural machinery, from both a macro-perspective and micro-perspective; which has been a tremendous help for the design and optimization of agricultural machines and their components. This paper reviewed the application research status of DEM in two aspects: First is the DEM model establishment of common agricultural materials such as soil, crop seed, and straw, etc. The other is the simulation of typical operational processes of agricultural machines or their components, such as rotary tillage, subsoiling, soil compaction, furrow opening, seed and fertilizer metering, crop harvesting, and so on. Finally, we evaluate the development prospects of the application of research on the DEM in agricultural machinery, and look forward to promoting its application in the field of the optimization and design of agricultural machinery.

Research on the Design of Agricultural Machinery Products Based on Ecological Thinking——Taking Sunflower Seedling Machine as an Example

This article describes the basic content and expression of ecological thinking, and explains how to apply the specific aspects of ecological thinking involved in high-efficiency, energy-saving, and environmental protection in the field of agricultural machinery design. This paper take the sunflower deseeding machine as an example, carry out innovative design research based on ecological thinking. Through the research and arrangement of relevant design elements and design principles and design practice, it provides new design ideas for the innovative design of sunflower threshing machines, and reflects the guiding role and application value of ecological thinking in agricultural machinery products.

INFORMATIONAL PHASE OF THE DEVELOPMENT OF EQUIPMENT FOR ANALYSIS OF DIRECT SHEAR AND PRE-COMPACTION OF THE SOIL

Given the real need for advances in studies such as the relationship of soil-machine dynamics, it is clear that there are almost no innovative systems developed to attend this demand. The design of agricultural machinery and equipment can be facilitated by having information and mechanisms that allow the prediction of the mechanized-set behavior in real work situation, especially regarding the traction effort demanded by the tractor, due to the energy demand of the equipment that interact directly with the soil. Obtaining this information usually requires high-cost imported laboratory equipment. Thus, the objective of this work was to obtain the design specifications for the development of a direct shear and soil pre-compaction analysis equipment with low manufacturing cost. The Phases Methodology was used to obtain the necessary parameters, in the informational phase of the desirable aspects for each design requirement. Through a step-by-step analysis, it was possible to obtain customers’ needs, together with the establishment of the desired criteria, and the design requirements for the new product development was generated. The use of the Phases Model allowed the transformation of customers’ requirements into the design requirements, enabling hierarchization by degree of importance and thus enabling the execution of future steps.

ACTIVE VIBRATION REDUCTION IN AGRICULTURAL MACHINERY

In article possibility of active suppression of vibrations of elements of a design of agricultural machinery is investigated. It is shown that it is possible to achieve the effective suppression of vibrations without the use of complex and expensive technical solutions, complex and time-consuming calculations and without conducting many experiments. The results of experimental research into active vibration suppression are covered.

Improving the use of multi-link tractor-transport trains

The use of multi-link tractor-transport units has become one of the most effective methods of increasing agricultural productivity. When turning these aggregates, an increase in the width of the transport corridor serves as a deterrent. (Research purpose) The research purpose is in improving the safety of multi-link tractor trains by optimizing the width of the transport corridor in the turn with the use of additional devices that contribute to the formation of safe driving conditions for tractor-transport units. (Materials and methods) Authors have developed a design of agricultural machinery, the use of which allows meeting the safety conditions. Based on existing methods, authors have created special methods for determining the effect of the proposed device on the angle of rotation of the drawbar relative to the tractor and trailer. The article presents analytical dependencies for determining the turnability coefficient and the transmission coefficient of the device's impact on the drawbar rotation angle. (Results and discussion) It was found that the change in the angle of rotation of the guide wheels of the trailer is greatly influenced by the length of the retractable rod of the hydraulic cylinder of the device. It was found by experimental studies that in the proposed device, there is a direct link between the length of the retractable rod of the hydraulic cylinder and the angle of rotation of the plan-washer. (Conclusions) To ensure the necessary transport corridor of the unit, it is necessary to adjust the angle of rotation of the drawbar of both trailer links. As a result of the conducted research, the existing relationships that arise during the operation of the proposed device are confirmed and it is proved that the coefficient of impact transmission in both cases is equal to one.

Rapid Design System for Agricultural Machinery Using Knowledge-Based Engineering: Case Study of a Wheeled Combine Chassis

HighlightsA knowledge-based rapid design system for combine chassis is proposed.Object-oriented knowledge representation uniformly describes the multi-source heterogeneous design knowledge.Multivariate linear regression analysis ratiocinates further unknown design principles behind existing products.Abstract. In the design of agricultural machinery, the lack of systematic and structured knowledge utilization systems results in low development efficiency and poor reusability of design knowledge. This study considers the design of a combine chassis and focuses on the application of knowledge-based rapid design to agricultural machinery. As a typical sophisticated agricultural machine, combines have a complicated design that requires the integration of multiple disciplines according to the crop types, production areas, and ability of the designers. Hence, a knowledge-based design system for a wheeled combine chassis is proposed. By integrating object-oriented technology with a mixed reasoning strategy, multi-source heterogeneous design knowledge can be applied in completing the chassis design task. To date, there are more than 2000 design ideas and 350 parameter models in the knowledge database. In addition, tacit design knowledge acquired by a knowledge discovery method can be employed to perfect the design and improve the reliability of the product. The design of a combine chassis demonstrates that the knowledge-based rapid design of agricultural machinery is completely feasible, and the design system significantly reduces the design workload, shortens the development cycle, and improves design efficiency and knowledge utilization. Keywords: Combine chassis, Knowledge-based design system, Knowledge-based engineering, Rapid design.