Mobile Power Units Research Articles

Conceptual directions for the development of driverless agricultural mobile power units

BACKGROUND: Currently, major global developers and manufacturers in the field of mobile agricultural machinery are working on the development of agricultural robotic systems. Particular attention is paid to the development of universal driverless mobile power units (MPU) capable of performing various technological operations autonomously, without human intervention. In the future, this makes it possible to exclude the operator from the MPU control process and to reconsider approaches to the issue of increasing the efficiency of technological operations. The existing trend of productivity improvement by increasing the main parameters of the unit, such as operating width, operating velocities, load capacity, etc., may change to an alternative path consisting in the use of numerous autonomous small-sized units comparable in performance (a swarm of agricultural robots). Thus, the use of driverless control systems makes it possible to use conceptually new approaches to the development of agricultural MPUs. In this regard, it becomes relevant to conduct the study aimed at identifying promising conceptual directions for the development of driverless MPUs and evaluating the efficiency of their application. AIM: Identification of conceptual directions for the development of driverless driverless MPUs and a theoretical assessment of the efficiency of their application. METHODS: The study object was the MPU transformation in the context of the development of driverless control systems. The study was based on scientific publications on the development of robotic agricultural tools, informational data of manufacturers of agricultural tractors and control systems for agricultural machinery. In the course of the study, such methods as information analysis, synthesis, methods of performance analysis of agricultural units and analysis of present cost of performing technological operations, adapted for driverless MPUs by the VIM, were used. RESULTS: The prospects for the introduction of driverless MPUs, the existing digital and intelligent control systems of MPUs and the main factors hindering their development are analyzed. A classification of agricultural MPUs according to automation levels is proposed. The main directions of development are identified and conceptual models of driverless MPUs are proposed: universal driverless MPUs (driverless tractors) with keeping the existing traction class and power classification, universal (multifunctional) low-power driverless MPUs of the only traction class, separate power modules capable of being combined into a single driverless unit based on the coupled agricultural machine. The method is proposed and the equivalent number of driverless MPUs of each conceptual model for each traction class is calculated. An assessment of the impact of the use of the proposed conceptual models of driverless MPUs on the arable unit performance and the present cost of arable operations has been carried out. CONCLUSIONS: Conceptual models for the advancing of driverless MPUs have been developed and comparative calculations of the efficiency of their application as part of arable units, helping to assess the possible prospects for their use, have been made.

Improving the Environmental Efficiency of a Mobile Power Plant with a Low-Emission Gas Generator

A mobile power unit is proposed to prepare for the processing of municipal solid waste using an environmentally friendly boiler unit developed by "Baltkotlomach" LLC. The design, principle and results of operation of an integrated combustion product purification system are presented. The conclusion was made that the developed power system meets environmental requirements and allows for efficient disposal of municipal solid waste.

О целесообразности использования сжиженного природного газа на рефрижераторных контейнерах с навесными дизель-генераторами

Objective: Analysis of the feasibility of using LNG as an alternative to diesel fuel in mobile power units used as a power source for refrigeration units of refrigerated containers. Methods: Natural gas has been compared to diesel fuel in terms of the economic characteristics; exergy analysis, systema111 tic approach, and synthesis have been used. Results: The economic feasibility of replacing diesel fuel with LNG for power units of refrigerated containers is determined; general issues of converting from diesel fuel to LNG were considered; possible ways of utilizing cold during regasification are proposed; emissions of harmful substances from the combustion of LNG and diesel fuel were compared. Practical importance: The study findings can be applied when converting mobile power units for various purposes from diesel fuel to LNG, as well as for in-depth analysis of individual problems of using LNG as a fue.

Justification of the requirements for an environmentally safety mobile power unit of class 1.4-2.0

The systematic analysis of world trends in the development of production and sale of agricultural tractors has shown that advertising and exhibition trends of overstating the power and saturation of tractors with automation elements for Russia are technologically outdated. It is proposed to consider increasing energy efficiency and ensuring their environmental safety in the full life cycle as the main indicators of the competitiveness of agricultural tractors in the world market.

Agricultural tractors of the fifth generation

The article deals with the problem of substantiation of mobile power units (MPU) – tractors for agriculture of the fifth generation. This issue is quite relevant. The main purpose of the work is to analyze agricultural tractors of the fifth generation. The authors formulated the main requirements for the ecological balance of the technogenic interaction of MPUs with production processes in agro-ecosystems of grain production in the zonal conditions of South-Russian arid agriculture. Proposals for the creation of new MPUs have been developed; the technological structures of machine aggregates based on the MPU of the fifth generation of classes 3, 5-6 and 8 that determined the technical schemes of the named MPU were determined. Analytical models for calculating the power characteristics of MPU of the named classes in deterministic and stochastic modes in relation to the most energy-intensive operations with definitions of the mathematical expectations of MTA’s power and performance. Also, an analysis of the MTAs effectiveness based on new MPUs upon criterion of the time spent on cultivating crop rotations on the examples of peasant farms and agricultural organizations (APC, CAE, etc.)

Analysis of methodological approaches and de-velopment of principles for describing properties characterizing the dynamics of the emission and spreading of toxic components of plants of the fuel and energy complex

The article gives a complete description of the pollutants properties and their behavior patterns based on studies considering the peculiarities of a continuous medium, on the one hand, and a set of discrete particles of different sizes, on the other. For that purpose, the authors used the theory of disperse systems, based on the classical concepts of colloidal and physical chemistry. The article presents the methodology developed by the authors to generalize, systemize and describe the properties and behaviour patterns of toxic components of exhaust gases from public and domestic power units, power plants, and exhaust gases from mobile power units for the dynamic conditions for their formation and spreading in the air basin of urban areas. It allows controlling the behavior of toxic components of exhaust gases in order to reduce air pollution and ensure the environmental safety in the builtup areas.

Theory of turn bodies of mountain tandem wheeled self-propelled chassis

The theory of turning of the adaptive bodies of mountain tandem-wheeled motor vehicle chassis intended as power units in small farms, is offered. A calculating formula for radius of turning is deduced for two variants: drive of all the six driving and steered wheels and without drive of front steered wheels. By the calculating formula are considered: lateral leading away of front steered wheels; re-distribution of the load on the wheels; hook resistance; coefficient of the differential gear black system; distance between centers of jointed in pairs tandem wheels constituting a counter-balanced suspension and other geometric, kinematic and dynamic parameters. The research results can be used in determining of exploitation indices of perspective mobile power units in the stage of their design.

Effectiveness of protection of mobile power unit cab from direct solar radiation

For normalization of microclimate in the cabs of mobile power units, it is necessary to introduce a particular technology of solar protection. The modern cabs have a high degree of light transmission, which enables intensive irradiation of operator on all sides. It results in a hyperthermia leading to the adverse health consequences for operator. The insolation flow also has impact on the electronic equipment, plastic parts and various elements of the cab. The applied means of protection, such as tinted glasses, films, covers and curtains, could not completely solve the problem. The study aim is the analysis of intensity of insolation, assessment of its value in form of quantitative characteristics, and search of the ways of its neutralization by acceptable technical means. One of the rational means limiting the impact of insolation flow is the use of blinds. The blinds designed according to the proposed scheme are able to limit significantly the direct solar flux, providing simultaneously an acceptable visibility during the movement of mobile power unit. This is achieved by the positioning of slats of blinds in the direction of sighting lines at different angles. The major efficiency characteristic of blinds is the transmission bandwidth of direct beams. It shows the design efficiency and allows to quantify the value of transmitted solar flux. For assessment, the geometric approach is proposed. The quantitative relationships received in the course of calculations are compared with experimental geometrical measurements, having a very close convergence of numerical results. The evaluation of blinds effectiveness is presented in form of the protection factor indicating the value of reduction of direct insolation. The proposed protection has a high efficiency and reduces the direct insolation by 1,75-170 times.

Unmanned mobile power unit for agricultural purposes

It is shown that the basis of robotic technologies in plant cultivation is an unmanned mobile power unit for agricultural purposes on wheeled or tracked platform with hybrid power plant, motion control and machine vision equipment. Description of software algorithm and schematic circuit diagram of motion control are given. It is noted that machine vision is an integral part of working organs, because much of the information about the state of plants (growth rate, maturity degree, disease) is received through visual contact, as well as through systems of motion control and precise positioning. This information allows the robotic working organs to find the technological solutions and implement the required operations, and the unmanned mobile power unit to move on process route. Another fundamental function of unmanned mobile power unit is positioning and motion control on required trajectory. A brief analysis of implementation of this function by means of satellite navigation or ground facilities of positioning including machine vision and target indication is given. Satellite navigation systems provide positioning and identification on large areas, but do not work indoors. Network wireless system of local positioning allows to control the location and motion of objects and reliably identify them both outside and inside the premises. Combined application of such systems allows to extend the motion control of vehicles and agricultural machines to areas not directly visible for satellites: covered yards, buildings. That creates additional opportunities for control of local movements of products and personnel in industrial and non-industrial premises of closed and open type.

Robotics technology and agrochemical support of plant cultivation

The article provides an overview of methods for monitoring of crop condition and variability (diversity) of soil fertility in the field. Two ways of their implementation having fundamental importance to robotic technologies are marked, namely the remote and at-ground ones. Remote methods for identification of diversity of soil fertility and crop condition are infrared spectrometry of crops by means of helicopters, quadcopters, drones and other low-altitude vehicles capable to shoot the condition of targets by means of attached camera, and also the radar-photometric remote sensing which allows to mark the field areas with different agrochemicals properties in real-time mode. Among the at-ground methods of agrochemical investigation of soils and crops special attention is payed to the mesh method of soil sampling with the use of automated samplers equipped with navigational devices, the usage of relation of soil fertility with its topography and the scanning of electrical conductivity of soil. The article presents a variant of identification of field contours of soil fertility during the automatic determination of productivity of crops (principally grain-crops) in harvesting process. A block diagram of implementation of this method is given. The obtained data is used for the construction of field productivity map, which allows to divide the areas (contours) on levels of productivity. A tracked chassis with hybrid power plant, motion control equipment and machine vision device is described. The chassis serves as the practical basis for development of robotic technologies in plant cultivation, including the fertilizer distributor that will become the base robotic unit in case of full robotization of agrochemical support of plant cultivation based on unmanned mobile power units.

Development prospects of robotic technologies in plant cultivation

It is shown that the basis of robotic technologies in plant cultivation is an unmanned mobile power unit for agricultural purposes on wheeled or tracked platform with hybrid power plant, motion control equipment and machine vision device. Technological operations are performed by technological robotic modules mounted on the platform.

Equipment for mobile power unit cab protection from insolation

The paper presents the analysis of equipment protecting the cab and operator of mobile power unit from high insolation. Special attention is payed to the combination of thermophysical properties of protection devices, including the capacities of reflection, thermal insulation and heat removal. A number of patented designs improving working conditions is proposed.

Mathematical models and methods for parameter optimization of air filter for mobile power units’ cabs

Mathematical models allowing to optimize the main characteristics of air supply system of mobile power units’ cabs are given.

Improvement of suspension system of mobile power units

Original designs of pneumatic-tyre movers and vehicle suspension are proposed. Their use will permit to increase reliability, operation durability, ride comfort, and cross-country capability of machine and tractor unit; to improve operator work conditions; to decrease vertical vibration and dynamic loads on supporting surface as well as soil compaction.

Parameterization of extra-low pressure tires for chemicalization mobile vehicles

Results of theoretical researches concerning parameter optimization of extra-low pressure tires for mobile power units are given. Optimal value of diameter and width of tire for chemicalization vehicles operating on grounds of low bearing value, were determined.

PRINCIPLES OF EFFICIENCY ESTIMATION TECHNIQUE OF MACHINE-PROCESS UNITS BASED ON THE FIFTH-GENERATION MOBILE UTILITIES

The problem of a comparative evaluation of a new technique design under developing the engineering solution and documentation is set. The created fifth-generation mobile power unit (MPU) is compared to the modern machine-process units based on a modern tractor identical in a draught class. The problem is solved through a numerically-analytical method with the parameter synthesis of the multipurpose machine-process units. The problem solution is reduced to detailed calculations in both variants. A nine-field grain zonal rotation rich in green sowing is considered. The analysis has shown that the created MPU with a variable-speed tram drive, two hinged systems unified in load-carrying capacity, and two power-takeoff shafts, will provide unit cost reduction actually caused by the design at a minimum 500 Rub./ha. MPU specifications are as follows: 50 kN class, 220 kW capacity, 9000…9500 kg weight. The essential novelty that distinguishes a new MPU from the standard tractors is provided through the usage of complex multipurpose operations.

Agricultural machine-building industry: urgent tasks

The production organization issue for five urgent technical means of engineering industry enterprises in Russian Federation is considered. The new economic assessment procedure of constructive, engineering and technological solutions is given, that can be used at designing of multipurpose machine and tractor unit based on mobile power unit of 5th generation.

A New Grain Harvesting System for Single-Pass Grain Harvest, Biomass Collection, Crop Residue Sizing, and Grain Segregation

A cereal grain harvesting system is introduced that combines existing technologies in a unique way to improve cereal grain harvest performance, increase profitability, and efficiently collect biomass. The harvesting system is comprised of three machines: one to reap grain, harvest biomass, and size crop residue for no-till seeding; a second to thresh and winnow the grain; and a third to separate the grain by quality for added value. This study describes the new harvesting system and the development of one of the system's major components: the reaper/flail harvester. The reaper/flail harvester consists of a mobile power unit, a stripper header to harvest the crop, and a flail to chop the standing residue into small pieces. A prototype harvester was fabricated and tested to determine system design criteria and performance characteristics in terms of machine power requirements, quantity of biomass collected, and bulk density of the material harvested. Trials were conducted in seven wheat (Triticum aestivum L.) fields in Oregon during 2005 and 2006 that ranged in yield from 3.3 to 6.4 t ha-1. Harvester performance was evaluated at various travel speeds, straw chop heights, and with different types of wheat. Flail power requirements were highly linearly correlated with quantity and rate of biomass chopped (R2 = 0.91). The maximum reaping power requirement was 2.7 kW m-1, only slightly higher than the no-load power requirement of 1.9 kW m-1. Power requirements for reaping, conveying, and flailing ranged from a low of 5.0 to a high of 13.5 kW m-1 depending on travel speed, crop yield, biomass concentration, and chop height. Values were linearly correlated with the combined grain, chaff, and biomass feed rate (t h-1) with an R2 of 0.88. Total machine power requirements for a harvester with a 7.3 m header would be about 175 kW, including 75 kW for propulsion, losses, and reserve. Chaff yield in the grain/chaff (graff) mixture harvested exceeded 2 t ha-1 in six of the seven trials. With chaff valued at $23 t-1, collecting 2 t ha-1 of chaff would increase farm revenues by $46 ha-1. Realistic graff densities of awned wheat were less than 1/11 that of clean grain, and new, efficient material handling systems would need to be developed to have harvesting capacities comparable to that of a conventional combine-based system. Awnless wheat had graff densities that averaged about 1/5 that of clean grain. Equipment is commercially available to handle this volume of material and have harvesting field capacities comparable to that of a conventional combine-based system.

04/00695 On the nature, capability and reversibility of hydrogen storage in novel carbon nanomaterials for mobile power units: Nechaev, Y. S. and Alexeeva, O. K. International Journal of Hydrogen Energy, 2003, 28, (12), 1433–1443

04/00695 On the nature, capability and reversibility of hydrogen storage in novel carbon nanomaterials for mobile power units: Nechaev, Y. S. and Alexeeva, O. K. International Journal of Hydrogen Energy, 2003, 28, (12), 1433–1443

On the nature, capability and reversibility of hydrogen storage in novel carbon nanomaterials for mobile power units

On the basis of the thermodynamic analysis of most representative recent data on hydrogen storage in graphite and novel carbon-based nanomaterials of sp 2 hybridization, the open questions have been studied of the nature, capability and reversibility of such storage, particularly, for mobile power units. For an interpretation of the thermodynamic and kinetic (diffusion) characteristics obtained in such a way, the known results have been used of ‘ab initio’ molecular orbital study of adsorption of atomic hydrogen on graphite and carbon nanostructures.