Design Of Agricultural Machinery Research Articles

Determination of Ergonomic Factors of the Backpack Blowers Used in the Windrow of Hazelnuts

Ergonomics plays an important role in the design and use of agricultural machinery to protect the health and safety of workers. Lack of ergonomic design negatively affects worker discomfort and safety. Therefore, ergonomic design should ensure that workers can work comfortably, maintain correct posture, and minimize the risk of injury. Especially workers using backpack machines are exposed to physical fatigue, posture problems, risk of injury, and ergonomic effects due to vibration and noise. Considering all these, this study was conducted to determine the ergonomic factors (ergonomic analysis of the operator's working posture, operator's fatigue values, noise level, and dust concentration) that the operator is exposed to as a result of different body positions and moving the air diverter hose while using the backpack type blowers used to windrow the kernel+husked nuts falling on the orchard ground during the hazelnut harvest period. The identification of ergonomic factors is also very important to improve the user experience, prevent occupational accidents, and improve machine performance in general. With the identification of these factors, optimized solutions for the safety and comfort of users will be put forward by adopting a human-centered approach in machine design.

Construction and parameter calibration of potato double‐layer flexible bonding model based on discrete‐element method

AbstractThe current discrete‐element simulation models for potatoes are multisphere polymer models derived from the Hertz–Mindlin (no slip) contact model in the discrete‐element simulation software (EDEM). These models oversimplify by considering potato peel and flesh as sharing identical mechanical properties within the structure. This oversimplification impedes a thorough investigation of the characteristics and mechanisms underlying potato peel‐breaking damage during mechanized harvesting, making in‐depth exploration challenging through simulation experiments. Consequently, this study conducted laboratory tests to determine the water content of potato peel and flesh, as well as the friction coefficients and collision recovery coefficients for various material pairs: flesh–steel, peel–steel, peel–peel, peel–flesh, and flesh–flesh. Subsequently, based on these findings, a double‐layer flexible bonding model for potato samples and whole stems under specific water content conditions was developed using EDEM software. The bonding parameters of the double‐layer flexible model for potato samples were refined through virtual shear calibration tests, leading to the identification of the optimal parameter combination: Flesh particle–flesh particle normal stiffness(tangential stiffness) per unit area X1 = 4.39 × 108 N/m3, peel particle–flesh particle normal stiffness(shear stiffness) per unit area X3 = 1.81 × 109 N/m3, peel particle–peel particle shear stiffness per unit area X6 = 1.99 × 109 N/m3, peel particle–peel particle critical normal stress X7 = 2.06 × 109 Pa. To validate the accuracy of the bonding parameters, shear and compression validation tests were conducted on entire potato stems. Comparison of the validation results from laboratory tests and simulation tests revealed an average relative error of e = 3.25%, signifying the feasibility of the constructed double‐layer flexible bond model for potatoes. This model meets the requirements for studying the characteristics and mechanisms of peel‐breaking damage in potatoes.Practical ApplicationsThe paper introduces a novel double‐layer flexible bonding model for potatoes using the discrete‐element method (DEM), which accurately simulates the mechanical properties and damage characteristics of potato peels and flesh. This research has significant practical applications in agricultural machinery design, improving the efficiency and reducing the damage during mechanical harvesting. By providing a more realistic simulation of potato behavior under mechanical stress, it can guide the development of gentler handling equipment, reduce waste, and enhance the quality of harvested potatoes. This contributes to optimizing the post‐harvest process, ensuring better storage, and extending the marketable life of potatoes.

Academician V.N. Boltinsky’s Scientific article Legacy in Agricultural Engineering Education and Science (Commemorating the 120th Anniversary of the Birth)

The article delves into the scientific contributions and advancements of the eminent Russian scientist in agricultural tractor construction, Vasily Nikolaevich Boltinsky. (Research purpose) The paper aims to shape and consolidate historical, scientific, engineering and technical concepts regarding the establishment and development of scientific and pedagogical institutions focused on the study of tractor engine operation and machine-tractor units in unsteady modes. It also seeks to underscore the contributions made by Doctor of Technical Sciences, Professor, and Member of VASKHNIL, V.N. Boltinsky. (Materials and methods) The study employs a chronological approach, utilizing historical, scientific, and informational resources, including publications by prominent scientists and original works by the academician himself. The paper also analyzes and summarizes historical facts detailing the role of V.N. Boltinsky in enhancing the design and efficiency of Soviet tractors and machinery units. (Results and discussions) Throughout his career, from assistant to associate professor to vice-president of VASKHNIL, V.N. Boltinsky dedicated himself to developing and testing new models of both foreign and domestic tractor equipment. His extensive experience and years of research culminated in the publication of the monograph «Operation of a tractor engine under unsteady load», which extensively explores the impact of varying loads on engine performance. V.N. Boltinsky successfully solved problems related to enhancing the operational speed of machine and tractor units, as well as innovating the design of agricultural machinery. (Conclusions) The life and professional endeavors of V.N. Boltinsky serve as a shining example of dedication to science, education, and the professional advancement of engineering and scientific professionals. To honor his legacy, an annual scientific and practical seminar entitled «Academician V.N. Boltinsky Readings» is held in Russia, ensuring his contributions continue to be celebrated and remembered.

A Review of Contact Models’ Properties for Discrete Element Simulation in Agricultural Engineering

In agricultural engineering, the discrete element simulation of the operational structure, object of movement, and force has become a standard method of modern agricultural equipment design. The selection and development of an appropriate contact model are critical factors affecting the accuracy of the process of the simulation calculation of the movement and force. Understanding how to choose or establish suitable contact models according to different research fields, objects, and purposes has become the focus of present research. This paper gives an overview of contact models for discrete element simulation, summarizes and analyzes the simulation calculation basis of different contact models, and focuses on the application status and scenarios of different models at this stage. It analyzes and summarizes the selection basis and application fields of contact models. The next direction in the development of discrete element simulation contact models should be the hybrid application of multicontact models and the precise development of specialized contact models. It is necessary to establish a standardized parameter-calibration process for different contact models to guarantee the accuracy of the models, to improve the application of computer arithmetic, and to establish an efficient and accurate simulation contact model selection and application in the field of agricultural engineering. Efficient and accurate simulation contact model selection, design theory, and calculation processes will improve the efficiency of modern agricultural machinery design.

ИСТОКИ РАЗВИТИЯ АГРОИНЖЕНЕРНОЙ НАУКИ В РОССИИ

The paper is devoted to the study of new materials on the origins of the development of agroengineering science in Russia, stored in the collections of the Museum of Agricultural Mechanics named after V.P. Goryachkin RGAU - MSHA named after K.A. Timiryazev. (Research purpose) The research purpose is analyzing the development of agroengineering science in Russia in the initial periods of its formation. (Materials and methods) It was noted that the newly opened documents more fully cover the key role of V.P. Goryachkin in the creation of the Faculty of Agricultural Mechanics at the Agricultural Academy named after K.A. Timiryazev, in the construction of a machine testing station, in the formation of advanced training courses for teachers in the field of agricultural engineering. We studied the materials of the commission chaired by Professor V.P. Bushinsky, created to draw up projects and estimates for the construction of the Moscow Institute of Mechanization and Electrification of Agriculture in 1930 (now the Institute of Mechanics and Power Engineering named after V.P. Goryachkin as part of the RGAU - MSHA named after K.A. Timiryazev). Documents relating to the opening of the All-Union Institute of Agricultural Engineering in 1928 were put into scientific circulation, in particular, the transcript of V.P. Goryachkin's report at the meeting of the Institute of Agricultural Mechanics, renamed VISKHOM, on November 25, 1927. (Results and discussion) They showed various forms of pedagogical work that appeared as a result of the decree of the Council of People's Commissars of the RSFSR "On agricultural engineering" dated April 1, 2021. (Conclusions) By the beginning of the 1930s in the USSR, V.P. Goryachkin, an outstanding scientist and organizer of science and education, laid the foundations of domestic agricultural engineering; for the first time put forward scientific principles for the design, calculation and construction of agricultural machinery and tools; developed a test methodology; created a number of unique devices and apparatus.

Simulation of Plastic Deformation Failure of Tillage Tools Based on the Smoothed Particle Hydrodynamics Method

The problems of large deformations, failures, and fractures that agricultural tillage tools may encounter during the cultivation process has long been a concern in the field of agricultural machinery design and manufacturing. It is important to establish a more accurate numerical model to effectively predict tools’ plastic deformation failures and ductile fracture failures. This research develops a numerical model for predicting the plastic deformation failure and ductile fracture failure of agricultural tillage tools using the smoothed particle hydrodynamics (SPH) method and the Johnson–Cook constitutive model. The model uses the Drucker–Prager criterion to describe the elastic–plastic constitutive behavior of the soil, the von Mises criterion to describe the Johnson–Cook constitutive model of the tool, and the coupling condition with the Lennard-Jones repulsive force to describe the interaction between the tool and soil. The numerical results show that the proposed model can effectively simulate the interaction between the tool and soil, as well as the tool’s plastic deformation failure and ductile fracture failure during the agricultural cultivation process. It can also predict the variation trend of the cutting force of the tool. This helps to provide a new approach for the numerical simulation of such problems.

Engineering Properties of Onion Seeds for Sustainable Agricultural Machinery Design

The engineering properties of the crop are an important factor in effectively designing agricultural machines. In terms of onion seeding or planting, various physical, mechanical, and frictional properties play a crucial role in the development of planting machines and performance assessment. The study on the engineering properties of onion seeds and their implications for agricultural machinery design supports the adoption of sustainable agricultural practices. Efficient and precise planting systems can optimize resource utilization, reduce wastage, and enhance overall agricultural productivity. This focus on engineering aspects in machinery design indirectly contributes to sustainable agriculture practices, which prioritize minimizing environmental impacts while ensuring food security. Ultimately, by emphasizing the importance of engineering properties, the study promotes the development of agricultural systems that align with sustainability goals. In this study, various engineering properties of onion seeds concerning the different soaking times have been studied. An experiment was performed to assess the change in engineering properties of onion seeds (Gavran, Puna fursungi, and KSP-117) by soaking them in water with a predefined duration (Dry seed, Day 1 and Day 2). The average moisture content of onion seeds varied from 9.44 to 40.87 % (d.b.). Sphericity, aspect ratio, geometric mean diameter, and thousand seed weight varied in the range from 0.72 to 0.77, 0.71 to 0.76, 2.05 to 2.18 mm, and 3.50 to 6.75 g, respectively. The bulk density of onion seeds was observed in the range of 489.64 to 526.24 kg/m3. It was observed that there was a gradual increment in bulk density with an increase in soaking time. However, a gradually decreasing trend was observed in the case of true density. The true density of onion seeds varied from 1127.14 to 1245.64 kg/m3. The coefficient of friction of onion seeds on a selected material (Wood, Plastic, Mild steel, and Aluminum) showed gradual growth concerning the soaking time.

Design reuse method of corn picking device based on case-based reasoning

In order to shorten the design cycle of corn snapping mechanism, a case reuse design method of snapping devices based on user requirements was proposed. A matter-element model is used to build a case matter-element database and parametric model library together to form a case database; the case attributes are divided, the retrieval scope is narrowed through the matching of core parameters, and the similarity of matching parameters and performance evaluation parameters is calculated by using analytic hierarchy process and deviation maximization method to realize the retrieval of similar cases. The transformation relationship between the design requirements and the main driving parameters of the parametric model is established by using the rule association method to realize the case’s modification. The engineering discrete element method is used to simulate the reuse case, and an improved method is proposed according to the simulation results. The improved device is verified by simulation and field experiments. The results show that the operating performance of the improved snapping device is improved, and the feasibility and effectiveness of the design reuse method are verified, which can provide technical reference for the intelligent design of agricultural machinery and equipment.

Application of digital design technology in the design of intelligent agricultural machinery and equipment

Abstract Today, China has become the world’s largest agricultural machinery and equipment countries and the use of countries, agricultural machinery industry for more than a decade to maintain high growth, along with three revolutionary changes in agricultural technology, has initially ushered in the development of artificial intelligence stage. At present, relative to the weak foundation of China’s agricultural machinery standardization work and the requirements of high integration of technology and multidisciplinary integration of artificial intelligence, there are bottlenecks that constrain the problem. This paper makes a directional discussion on the direction of standardization breakthrough through the analysis of digital design technology and typical applications at home and abroad, the analysis of standard transformation of scientific and technological achievements, and the analysis of current problems. Aiming at technical standards development, implementation, and improvement to promote technological innovation, application, and improvement of intelligent manufacturing of agricultural machinery products. So that scientific and technological innovation continues to enhance the level of technical standards, technical standards continue to promote the transformation of scientific and technological achievements. Technical standards and intelligent agricultural machinery lend each other in international competition and become a strategic means to participate in international cooperation and competition. Accelerate the transformation of the old and new dynamics of the agricultural mechanization industry, and realize the standardization and internationalization of the intelligent agricultural mechanization industry.

Modeling Soil–Plant–Machine Dynamics Using Discrete Element Method: A Review

The study of soil–plant–machine interaction (SPMI) examines the system dynamics at the interface of soil, machine, and plant materials, primarily consisting of soil–machine, soil–plant, and plant–machine interactions. A thorough understanding of the mechanisms and behaviors of SPMI systems is of paramount importance to optimal design and operation of high-performance agricultural machinery. The discrete element method (DEM) is a promising numerical method that can simulate dynamic behaviors of particle systems at micro levels of individual particles and at macro levels of bulk material. This paper presents a comprehensive review of the fundamental studies and applications of DEM in SPMI systems, which is of general interest to machinery systems and computational methods communities. Important concepts of DEM including working principles, calibration methods, and implementation are introduced first to help readers gain a basic understanding of the emerging numerical method. The fundamental aspects of DEM modeling including the study of contact model and model parameters are surveyed. An extensive review of the applications of DEM in tillage, seeding, planting, fertilizing, and harvesting operations is presented. Relevant methodologies used and major findings of the literature review are synthesized to serve as references for similar research. The future scope of coupling DEM with other computational methods and virtual rapid prototyping and their applications in agriculture is narrated. Finally, challenges such as computational efficiency and uncertainty in modeling are highlighted. We conclude that DEM is an effective method for simulating soil and plant dynamics in SPMI systems related to the field of agriculture and food production. However, there are still some aspects that need to be examined in the future.

Review of Discrete Element Method Simulations of Soil Tillage and Furrow Opening

In agricultural machinery design and optimization, the discrete element method (DEM) has played a major role due to its ability to speed up the design and manufacturing process by reducing multiple prototyping, testing, and evaluation under experimental conditions. In the field of soil dynamics, DEM has been mainly applied in the design and optimization of soil-engaging tools, especially tillage tools and furrow openers. This numerical method is able to capture the dynamic and bulk behaviour of soils and soil–tool interactions. This review focused on the various aspects of the application of DEM in the simulation of tillage and furrow opening for tool design optimization. Different contact models, particle sizes and shapes, and calibration techniques for determining input parameters for tillage and furrow opening research have been reviewed. Discrete element method predictions of furrow profiles, disturbed soil surface profiles, soil failure, loosening, disturbance parameters, reaction forces, and the various types of soils modelled with DEM have also been highlighted. This pool of information consolidates existing working approaches used in prior studies and helps to identify knowledge gaps which, if addressed, will advance the current soil dynamics modelling capability.

MECHANIZATION OF AGRICULTURE IN THE SOUTHERN URALS: CONTRIBUTION OF E.M. KHARITONCHIK SCIENTIFIC SCHOOL

The process of formation and development of agroengineering scientific schools of the Southern Urals should be considered as part of the development process both in the country and in its various regions of its own agricultural engineering. (Research purpose) The research purpose is analyzing the directions of the scientific school of Yefim Mironovich Kharitonchik, and to identify its role in the development of the process of mechanization of agriculture in the region. (Materials and methods) Analyzed the work activity of E.M. Kharitonchik related to the production of agricultural machinery at factories in Moscow and the Moscow region. It was shown that the first scientific developments were works on the creation and improvement of instruments and testing machines, as well as designs of tractor units and systems. (Results and discussion) It was revealed that the following areas of the scientific school of Kharitonchik have gained great fame: modification of tractor engines; development of the theory of specific parameters of tractors; evaluation and optimization of parameters of tractors and their aggregates; study of vibrations of tractor engines; creation of hydrostatic drives of active trailers for heavy-duty road trains. (Conclusions) The information given in this article allows us to build a chronological chain of work of the scientific and engineering thought of the scientific school of the Southern Urals in the field of design and operation of agricultural machinery.

A Novel Agricultural Machinery Intelligent Design System Based on Integrating Image Processing and Knowledge Reasoning

Agricultural machinery intelligence is the inevitable direction of agricultural machinery design, and the systems in these designs are important tools. In this paper, to address the problem of low processing power of traditional agricultural machinery design systems in analyzing data, such as fit, tolerance, interchangeability, and the assembly process, as well as to overcome the disadvantages of the high cost of intelligent design modules, lack of data compatibility, and inconsistency between modules, a novel agricultural machinery intelligent design system integrating image processing and knowledge reasoning is constructed. An image-processing algorithm and trigger are used to detect the feature parameters of key parts of agricultural machinery and build a virtual prototype. At the same time, a special knowledge base of agricultural machinery is constructed to analyze the test data of the virtual prototype. The results of practical application and software evaluation of third-party institutions show that the system improves the efficiency of intelligent design in key parts of agricultural machinery by approximately 20%, reduces the operation error rate of personnel by approximately 40% and the consumption of computer resources by approximately 30%, and greatly reduces the purchase cost of intelligent design systems to provide a reference for intelligent design to guide actual production.

Study on the Dynamic Cutting Mechanism of Green Pepper (Zanthoxylum armatum) Branches under Optimal Tool Parameters

In order to design a branch-cutting type green pepper harvesting device, we firstly study the whole process of straight knife green pepper cutting to reveal the cutting mechanism and provide theoretical guidance to the design. A finite element model was established for the cutting of pepper branches across the distance, and single-factor and multi-factor finite element simulation tests were conducted on the knife feed angle, tool edge angle, and knife feed speed of the working parts of the pepper cutting and harvesting device. The results of the experiment were analyzed by ANOVA, which showed the different degrees of importance of these factors, and the optimal parameters were obtained by response surface methodology (RSM). With the optimal parameters selected, the predicted maximum cutting force and cutting completion were 803.35 N and 98.58%, respectively, this satisfies the efficiency and economy requirements of agricultural machinery design. In addition, the cutting force of green pepper branches was analyzed and a theoretical mechanical model was developed to help us understand the variation of cutting force numerically. The stress–strain system, high-speed photography system and numerical prediction were innovatively combined to observe and measure the stress and other key state variables in the cutting process in detail, summarize their changing trend, and establish a time-based monitoring and comparison model. The above research results can provide a reference for the design of green pepper branch cutting and harvesting devices, such as direct guidance on the selection of working parameters, materials, etc., and guidance on the operation in actual work.

Effects of Moisture Content and Grain Type on Mechanical Properties of White Rice: Literature review and Experiment

The mechanical properties of agricultural grains are required in the design of agricultural processes and machinery. These properties are influenced by moisture content and grain type. This study aimed to determine the effect of moisture content and grain type on the mechanical properties of white rice. There are three different types of white rice, namely short-bold (Koshihikari), long-medium (IR 64), and very long-slender (Basmati) grains within three levels of moisture content of 9%, 14%, and 19% were used as the samples in the experiment. The experiment was designed into Completely Randomized Design, factorial 3 x 3. The dimension, internal friction angle, and rupture force of the grain samples were respectively measured using a digital calliper, direct shear cell apparatus, and compression test apparatus. It could be concluded that moisture content, grain type, and the interaction of these two factors significantly affected almost all parameters of the mechanical properties of white rice. Most of the relationships between the parameters of mechanical properties and moisture content could be expressed as linear equations.

Strength properties of the Bambara kernel (Vigna subterranean) as influenced by the moisture content and kernel size

The fracture resistance of food grains is an essential piece of information required for the optimum design and development of agricultural post-harvest machinery. In this study, the strength properties of two varieties of Bambara kernels (TVSU-1395 and TVSU-1353) were examined in terms of the mean rupture force, absorbed energy, and deformation as affected by the moisture content and kernel size. To achieve this, a quasi-compressive force was applied on the two varieties of Bambara kernels of varying moisture contents (5.43%, 7.24%, 9.01%, 11.54%, and 13.62% wb) and kernel sizes (small, medium, and large) in between the loading compartments of a universal Testometric device at a 20 mm/min loading rate. The experiments take ten treatments with 20 replications subjected factorially to a completely randomised design (CRD) into consideration. The results revealed that the force needed to initiate the kernel fracture increased with an increase in the kernel size and moisture content from 101.44 to 235.06 N and 74.69 to 190.49 N for TVSU-1395 and TVSU-1353, respectively; whereas the energy at the kernel fracture point increased in a range of 0.074 to 0.401 J and 0.062 to 0.141 J for TVSU-1395 and TVSU-1353, respectively. The kernel deformation increased with the moisture content and size from 0.654 to 3.746 mm. These infer that the large kernel size of the TVSU-1395 variety at a 5.4% moisture content had greater compressive strength than the TVSU-1353 variety. The kernel moisture and size exhibited a strong correlation (0.958 ≤ R<sup>2</sup> ≤ 0.997) with the strength parameters. The results of this study will help the food industry in designing energy-efficient post-harvest equipment for Bambara kernel processing. Further studies may consider the strength attributes of Bambara kernels at varying rates of loading, kernel orientations, and varieties to optimise the best process conditions for the post-harvest handling of different Bambara cultivars and develop labour-saving decorticating machines.

Research on Dynamic Load Characteristics of Advanced Variable Speed Drive System for Agricultural Machinery during Engagement

A wet clutch is the key component to realize power uninterrupted in agricultural machinery operation. To reduce impact of the system and improve engagement quality, this paper studies and establishes the dynamic load characteristics model of a wet clutch and analyzes three kinds of tractor working conditions. This paper proposes and adopts the method of combining ‘PLS analysis-Improved SA—Comparison of various models-Actual test data’. The results show that with the limit of 100 Nm, the relationship between dynamic load characteristics and oil pressure is opposite. Load is highly inversely correlated with dynamic load, and it has enough precision to build a power curve model only by load (MAPE is 4.5929%). Take a certain type of tractor for example, oil pressure should be maintained at a low level, plowing resistance should be greater than 1600 N and the mass of transportation should avoid 600~1800 kg. This study provides a direct basis for the control, design and performance improvement of agricultural machinery.

Experimental Study on the Mechanical Properties of Friction, Collision and Compression of Tiger Nut Tubers

The mechanical properties of agricultural materials can provide the basis for the design and optimisation of agricultural machinery. There are currently very few studies on the mechanical properties of tiger nut tubers, which is not conducive to the design and development of machinery for their harvesting and processing. To obtain the mechanical parameters of tiger nut tubers, this study investigated the effects of variety (Zhong Yousha 1 and Zhong Yousha 2), moisture content (8%, 16%, 24%, 32% and 40%), contact material (steel, aluminium, plexiglass and polyurethane), release height (170 mm, 220 mm, 270 mm and 320 mm), loading speed (5 mm/min, 10 mm/min, 15 mm/min and 20 mm/min), compression direction (vertical and horizontal) on the friction, collision and compression mechanical properties of the tubers. The results were as follows: Both moisture content and contact material had a significant effect (p < 0.01) on the sliding friction coefficient (0.405–0.652) of the tubers; both variety and moisture content had a significant effect (p < 0.01) on the angle of repose (27.96–36.09°); contact material, moisture content, release height and variety all had a significant effect (p < 0.01) on the collision recovery coefficient (0.376–0.672) of tubers; variety, loading speed, moisture content and compression direction all had significant effects (p < 0.01) on the damage force (87.54–214.48 N), deformation (1.25–6.12 mm) and damage energy (82.38–351.08 mJ) of the tubers; only moisture content and compression direction had significant effects (p < 0.01) on the apparent elastic modulus (12.17–120.88 MPa) of the tubers. The results of this study can provide a reference for the design and optimisation of machinery for the harvesting and processing of tiger nut tubers.

Research on Design of Intelligent Agricultural Harvester Based on QFD and AHP

In order to optimize the design of intelligent agricultural harvester, improve the backward situation of agricultural machinery design in western Guangdong, and explore new research methods to guide the design of modern agricultural harvester. Using QFD (Quality Function Deployment Principle), this paper analyzes the form and functional characteristics of the intelligent agricultural harvester, and from the aspects of optimizing the product appearance, product function, product quality and man-machine optimization of the intelligent agricultural harvester, establishes a house of quality matrix suitable for agricultural harvesters in western Guangdong. This paper analyzes the mapping relationship between the quality function and the design features of the intelligent agricultural harvester, determines the design feature factor framework and weight of the intelligent agricultural harvester, and obtains the importance values of the function features and design elements, so as to establish the priority of the design resources and function configuration optimization, and then guide the example design of the intelligent agricultural harvester. AHP (Analytic Hierarchy Process) is used to verify that the characteristic factors of QFD design are consistent with the user evaluation data, which proves that the design example scheme of intelligent agricultural harvester is feasible to some extent, and provides a new research idea for the design of the same type of agricultural harvesting equipment.

Prediction of cyclic durability and risk analysis of inconsistencies in the supporting structures of mobile vehicles

The reliability and safety of mobile vehicles is determined by their carrier system. Achieving a low probability of failure of structures and reducing the cost of equipment is possible by changing the traditional methods of predicting reliability and applying risk analysis, as well as using risk-based design. The aim of the work is to develop methods for predicting the cyclic durability of elements, fastening prefabricated load-bearing structures and analysis to achieve acceptable risks of mobile vehicles at the stages of risk-oriented design. The methods and standards were developed in order to provide methodological support of risk-based design. Those allow designers and engineers to use new methods of design and calculation of tractor and agricultural machinery. It is proposed to introduce into the existing notation system of design and technological documentation the identifiers for parameters as the priority indicators and to achieve when designing the probability of occurrence of each potential cause of failure up to a given level of risk, taking into account priority. The tool for achieving low failure probabilities is the construction of diagrams of cause-and-effect relationships of failures is the source of cause and effect based on the method of deduction and induction. A calculation and experimental method for predicting reliability, according to the criterion of cyclic durability of load-bearing structures and fasteners was developed. The technique is based on local modeling of damage initiation zones, taking into account the influence of design and technological factors of production, simulating the load mode of a mobile vehicle, its damage zones. The following are used for the calculation: finite element method, experimental load assessment, fatigue resistance characteristics of load-bearing elements, rivets and bolts, damage accumulation hypotheses. Risk analysis is carried out using the FMEA methodology. As a result of the risk analysis in a probabilistic formulation, a conclusion is made about the possible damage to the supplier the number of mobile vehicles that will not ensure the fulfillment of the stated requirements for a given resource and warranty mileage. Thus, data for assessing risks and making a decision on the advisability of redesigning equipment appear. The created methodological support for predicting cyclic durability and risk analysis for the implementation of risk-based design allows: to eliminate the uncompetitive level of product quality and production quality, as well as low efficiency and labor productivity; apply new design technologies, design and production preparation methods that reduce development time. The developed methods and means of the risk-based approach have been widely tested and are used in the practice of auto-tractor-agricultural machine building.