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gineering, control engineering, and information sciences (Figure 5). Mechatronics character-
izes a general trend of increasing automation. Previous products have treated the mechanical
and electronic design as separate entities. Fusion of these systems in design will lead to de-
creased costs in design and manufacturing and increased functionality. In effect mechatronics
becomes the implementation of systems engineering principles resulting in the efficient de-
sign of electro-mechanical systems.




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Figure 5. Mechatronics systems combine mechanical, electrical and computing tech-
nologies to create equivalent functionality (Zhang, 2003)

SYSTEMS APPROACH TO MANUFACTURING
Due to current agricultural equipment complexity, some agricultural manufacturers are
adopting systems engineering methods to reduce the costs of machinery and mitigate the risks
involved in the design and manufacture of ever more complex machinery. The systems ap-
proach proceeds with design synthesis and system validation while considering the complete
problem and product life cycle including disposal. In short, a systems approach considers
both the business and the technical needs of all stakeholders with the goal of providing a qual-
ity product that meets the user needs.
The systems approach has three major components as shown in Figure 6:




Figure 6. Systems approach to manufacturing (Reid, Schueller and Norris, 2003)

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ISBN 5-88890-033-8. Экология и сельскохозяйственная техника. СПб, 2005.


“Requirements Management” consists of requirements capture and allocation. Re-
quirements capture involves capturing and using stakeholder requirements to yield product
specifications while requirements allocation involves developing systems architecture possi-
bilities and systematic requirements traceability. The modular components of a system or
sub-system are defined by form, fit, function and input/ output definitions
“Top Down Design and Simulation” and “Bottom Up Design and Simulation” used in
the design process will improve product quality while eliminating prototypes, reduce product
delivery cycle time, and optimize machine performance. “Bottom Up Simulation and Analy-
sis” which involves simulation and analysis starting from the component level and working
upward. Examples include the finite element analysis of wheels and three-dimensional dy-
namic simulation of a tractor. Rapid prototyping, virtual simulation, and design for assembly
and manufacture are possible methods that may be involved. “Top Down Synthesis and Simu-
lation” involves product development (synthesis) from upper level requirements. For exam-
ple, fleet system simulation and optimization, synthesis of machine systems, to synthesis of
kinematics. An additional aspect of this process is the design of modular system architec-
tures.
Harms (2003) described the concept of simultaneous (or concurrent) engineering.
Without early and simultaneous involvement of all departments, specialists, suppliers and po-
tential external consultants, one can no longer develop ever more complex agricultural ma-
chines. In that case “simultaneous” means to be faster to the market, because all manufactur-
ers can contribute their expertise earlier, and also have the opportunity to use the expertise of
the various specialists as early as possible. Thus, the product quality and the market use is im-
proved simultaneously. In former times and with small machines, one could afford to have
machines designed and looked after by one specialist. Today this is no longer feasible due to
the fact that machines have become too complex. For various conditions in different markets
it is important to cooperate with a very high flexibility in the field of design, production, pur-
chasing, controlling and marketing.
In all parts of the industry there is great pressure on the development departments, Ta-
ble 5.
Table 5.
Pressure on the development department.(Harms, 2003)

Pressure on Time Pressure on Costs Pressure on Quality
short product life time increasing complexity realization of customers
request

quicker in the market outsourcing flexibility of development
process

accelerate development overhead expenses integration of special know-
process how


development process must be production expenses innovative concepts for new
shorter than product products
life time


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“Simultaneous (or Concurrent) Engineering“, is a process wherein products and pro-
duction equipment are developed simultaneously by interdisciplinary teams and sub-suppliers
are involved as early as possible. The main advantages of the SE-method are a much shorter
development period, lower development cost and earlier market presence.

AGRICULTURAL MECHANIZATION POLICIES:
Almost 30 years ago, Stout and Downing (1976) wrote about the need for a coherent
mechanization policy. They pointed out that in most countries development plans provide ba-
sic policy guidelines for agricultural development; but the component of these plans concern-
ing mechanization policy is generally weak or non-existent. This is a serious failing, for it is
increasingly recognized that mechanization profoundly influences factors such as the volume
and quality of production; the productivity of both land and labor; the cost of production; the
level of employment; migration of agricultural wage earners and farmers; land ownership pat-
terns; the development of mechanical skills and of manufacturing and service-related indus-
try; and foreign exchange. These are all very important factors for the national economy of
any country and each requires careful and deliberate consideration.
All governments should therefore work out a coherent and consistent set of aims and
approaches, which in aggregate constitute an agricultural mechanization policy, and should
make sure that the role of mechanization is understood by all.
Adequate mechanization policy involves much more than production and employment
considerations; in addition it includes objectives concerning consumer prices, land tenure,
conservation and energy. Some of the basic questions concerning mechanization it will at-
tempt to resolve are: Is tractor mechanization to be promoted? What operations should be fur-
ther mechanized? Where (i.e. to what particular crops, areas or production bottlenecks) should
mechanization be applied? What levels of mechanization (i.e. hand tools, animal-draft or trac-
torization) should be applied? What is the best way to promote the desired mechanization?
The major components of a mechanization policy may be broadly categorized as tech-
nical, on the one hand, and economic and social on the other. Before examining the various
technical considerations that should guide a mechanization policy, it must be emphasized that
a successful agricultural program, with or without mechanization, must include measures to
ensure the availability and proper use of modern inputs such as high yielding varieties, fertil-
izers, improved water control systems and crop protection chemicals as well as labor, draft
animals, hand tools, and engine powered machines.

TRAINING AND EDUCATION
One of the first priorities is to provide training and education for users of mechanical
equipment, whether hand operated, animal drawn, or motorized. Training facilities are needed
for mechanics, technicians and engineers, those who will design equipment, work as exten-
sion officers, conduct mechanization research and supervise mechanization programs.

MANUFACTURING, DISTRIBUTION, SERVICE AND REPAIR
Development of a local farm equipment industry provides alternative employment, re-
duces dependence on imports, saves foreign exchange and facilitates the supply of spare parts
and service. Adequate supplies of spare part are essential for the smooth and efficient opera-
tion of a mechanization program.




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IMPORTS AND JOINT VENTURES
Equipment designed for use in Europe and North America often has to be modified
and strengthened or even completely redesigned to ensure mechanical reliability and to fit in
with local agricultural practices. Joint ventures where international companies collaborate
with local manufacturers have become commonplace in recent years. Examples include Deere
and company’s joining with China’s state owned Tianjin Tractor Manufacturing Company
and CNH joining with the Shanghai Tractor and Internal Combustion Engine Corporation.

FUEL SUPPLIES
Engine powered equipment requires a steady, dependable supply of fuel, which is an
essential task of a mechanization policy to ensure, especially in times of shortages and higher
prices.

RESEARCH
Appropriate research on agricultural mechanization systems should be encouraged and
funded at existing national and regional institutions. These may be universities, institutes for
agricultural research, machinery testing centers or other agencies. Research can be strength-
ened by better financing, better qualified staff, better facilities, better communication between
agencies and disciplines, and integration with general agricultural research.

CREDIT
Since most farmers in less developed countries have accumulated very little capital,
any move to higher-level mechanization will require a supply of credit to small manufacturers
and farmers.

STORAGE, TRANSPORTATION, POST-HARVEST PROCESSING AND MARKETING
The goal of increased production assumes the existence of a market. Storage, trans-
portation and Post-harvest processing are important links between the farm and the market.

MECHANIZATION POLICY COMMITTEE
A special co-ordinating committee (or working group) should be appointed and made
responsible for drawing up a detailed mechanization policy and program to accelerate the de-
velopment and efficient application of equipment for agricultural production and post harvest
handling and processing. It activities might include:
1. a broad program of research to define the role of agricultural mechanization in
each country,
2. prioritizing mechanical research and development projects,
3. testing and functional evaluation as well as reliability and durability,
4. operating demonstration farms in cooperation with extension specialists,
5. collaborating with manufacturers,
6. provide extension services
7. economic and social considerations, effect on employment,
8. calculation of cost/benefit ratios

AGRICULTURAL/MECHANICAL ENGINEERING EDUCATION
Education and research has been discussed in the previous section, but another aspect
needs to be mentioned. In North America, Europe and other countries as well, the Power and
Machinery (mechanization) programs in many agricultural engineering departments have
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been severely reduced almost to the point of elimination. Many agricultural engineering de-
partments have added the word biological, or biosystems to the department name and some
have removed the word—agriculture. The idea is that the machinery manufacturers can pro-
vide all the needed engineering expertise. But where will the machinery companies find that
mechanical expertise? Certainly not in most of the agricultural engineering programs in US
universities. The same is true in many European universities. And FAO has recently down-
graded its mechanizations services. IRRI has nearly eliminated its once mighty mechaniza-
tion research program.
A recent article in the widely read US magazine, Successful Farming, decries this
move away from practical applications of agricultural engineering and mechanization. It cites
the example of a well-known practical agricultural mechanization specialist, Dr. Graeme
Quick, who was recently allowed to retire from Iowa State University and return to his home
in Australia. The author of this article, Dave Mowitz, asks where will we find the practical
engineers specializing in agricultural mechanization in the future? He writes, “Never mind
that agriculture is still the number one occupation in many states (in the US and around the
world) as well as the largest single industry in the country (US). Yet it seems that university
administrators are turning up their collective noses at production agriculture. At times they act
embarrassed to deal with the day-to-day aspects of farming and ranching.” (Mowitz, 2004)
My message to you---don’t let this situation develop in China or in other countries
where agriculture is so important to the national economy.

ENGINEERS---PART OF THE INTERDISCIPLINARY TEAM
Engineering has the potential to contribute to a wide variety of options to help increase
production and productivity and thereby reduce poverty and increase food security and safety.
All too often, however, we have missed opportunities by working on micro-studies in isola-
tion and interpreting our role too narrowly. We haven’t communicated our achievements ef-
fectively in terms that the public, policy makers, and other disciplines can appreciate. We are
very good at what we do, but too many of us are content to focus on micro-studies; that is,
problems with well defined boundaries that lend themselves to quantitative analysis. Many of
us are uncomfortable when faced with broad issues that may be poorly defined and often un-
bounded; problems such as poverty, illiteracy, unequal income distribution, and food security
and safety. We prefer to withdraw to our labs and develop and validate mathematical models
that have clearly defined, finite boundaries. We can then present our results with confidence
based on mathematical principles, the laws of physics, thermodynamics and so on. And this
type of work is important. We should be justifiably proud of our talents and accomplishments.
But the technical and mathematical aspect is only part of the picture; sometimes the easy part.
The fundamental objective of engineering should be to help people, so we must strive to be a
part of interdisciplinary teams that include social, economic and even political dimensions.
So my challenge to you is to look at the big picture---think globally and multidiscipli-
nary. Look for ways for industry and university/government engineers to work with other
specialists to solve bigger problems. Ask—what are the major agricultural-related problems
in the world today? And how can we contribute to solutions? We have already talked about a
systems approach for solving mechanical design problems, but now we are thinking about
working within a multidisciplinary environment. In this way engineering can have a direct
impact through research and development as well as an indirect impact by being a catalyst for
increasing the impact of other disciplines. By adopting a demand-led systems approach that
considers all stakeholders involved in the production to consumption chain, intervention
points can be better identified and targeted and R&D can be better focused to achieve outputs
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ISBN 5-88890-033-8. Экология и сельскохозяйственная техника. СПб, 2005.


appropriate for each target group. Combined with a problem-solving orientation rather than a
technology focus, hardware development becomes a tool and not an end in itself. To capture
the opportunities that a systems approach offers will require engineers to work more closely
with target groups in a more multidisciplinary environment. As such, it may be necessary to
develop or tap into a wider set of skills (such as economics, operations research, ergonomics,
business management, agronomy, etc.). Problem solving, not technology generation, must be
the focus.
Some big problems that agricultural engineers can address include feeding an expand-
ing world population, improving income distribution so everyone will have the purchasing
power to afford a balanced and nutritious diet (food security), natural resource conservation
and efficient management (soil, water, energy, etc.), maintaining the environment (preventing
soil degradation, maintaining water and air quality, etc.), maintaining food safety, and creat-
ing a safer workplace. Mechanization must be considered in the context of this broader set of
issues.
I also challenge you to become more involved with public policy issues and to let ad-
ministrators and policy makers know about the benefits of your work to society and to ensure
that agricultural engineering (mechanization) is on the national and local research priorities
list. No one person can do these things alone—it is up to all of us to broaden our horizons,
think and talk more about the impact of our work on humans; and thereby strengthen our pro-
fession and increase our service to humanity (Stout, 1997).

REFERENCE
AEM. 2004. “U.S. Ag Flash Reports.” Association of Equipment Manufacturers.
http://www.aem.org/Trends/USAg/ Accessed 25 September 2004.
Clarke, L. and C. Bishop. 2002. Farm Power—Present and Future Possibilities in De-
veloping Countries. Agricultural Engineering International: the CIGR Journal of Scientific
Research and Development. Vol. IV. Invited Overview Paper. Presented at the ASAE Interna-
tional Meeting/CIGR World Congress. July 30. Chicago. 19 pp. cigr-ejournal.tamu.edu
Firodia, A., R. Bacher, and K. Renius. 1999. Transfer of Technologies from Devel-
oped to Developing Countries: Experiences and Results in Asia and the Far East. The Case of
India. Proceedngs of the 10th Meeting of the Club of Bologna, Nov 14-15. pp 117-127.
Harms, H-H. 2003. Possibilities to Reduce Manufacturing Costs of Tractors and Agri-
cultural Equipment. Agricultural Engineering International: the CIGR Journal of Scientific
Research and Development. Vol. VI. Invited Overview Paper. Presented at the Club of Bolo-
gna meeting. Nov 16. 9 pp. cigr-ejournal.tamu.edu
Krutz, Gary W. and John K. Schueller. 2000. Advanced Engineering: Future Direc-
tions for the Agricultural and Biological Engineering Profession. Journal of Agricultural En-
gineering Research. 76: 251-265.
Mowitz, D. 2004. Practical Engineering at Risk. Successful Farming. September.
Reid, J., J. Schueller, and W. Norris. 2003. Reducing the Manufacturing and Manage-
ment Costs of Tractors and Farm Machinery. Agricultural Engineering International: the
CIGR Journal of Scientific Research and Development. Vol. V. Invited Overview Paper. Pre-
sented at the Club of Bologna meeting. Nov 16. 12 pp. cigr-ejournal.tamu.edu
Renius, K. 1989. The Industrial Process of Implementing Innovative Ideas to Farm
Machinery. Proc. 1st meeting of the Club of Bologna. Bologna, Italy. Pp. 57-66.
Renius, K. 2002. Global Tractor Development: Product Families and Technology
Levels. Proceedings Actual Tasks on Agricultural Engineering Symposium. Opatija, Croatia.
March 12-15. p 87-95.
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Schueller, John K. and Bill A. Stout. 1995. Agricultural Trends and their Effects on
Technological Needs for Farm Equipment in the 21st Century. Proc. Club of Bologna. Bolo-
gna, Italy. November 6-8. pp. 65-76.
Schueller, J.K. and T.M.P. Wall. 1986. Tractorisation and the Tractor Industry in In-
dia. ASAE Paper No. 86-5002.
Stout, B. 1997. Challenges and Opportunities for Agricultural Engineers. Resource
Magazine. American Society of Agricultural Engineers. Sept. p 19.
Stout, B. and C. Downing. 1974. Selective Employment of Labor and Machines for
Agricultural Production. Monograph No. 3. Institute of International Agriculture. Michigan
State University. East Lansing, Michigan. USA. 23 pp.
Stout, B. and C. Downing. 1974a. Selective Mechanization: a Hope for Farmers in
Developing Countries. Agricultural Mechanization in Asia. Summer. p. 13-17.
Stout, B. and C. Downing. 1975. Counterpull. FAO CERES. Jan-Feb. p. 43-46
Stout, B. and C. Downing. 1976. Agricultural Mechanization Policy. International La-
bor Review. 113(2): 171-187.
Stout, B. and B. Cheze (Ed). 1999. Plant Production Engineering. CIGR Handbook
Vol III. American Society of Agricultural Engineers. 632 pp.
Zhou, X., R. Dong, S. Li, G. Peng, L. Zhang, J. Hou, J. Xiao and B. Zhu. 2003. Agri-
cultural Engineering in China. Agricultural Engineering International: the CIGR Journal of
Scientific Research and Development. Vol. V. Invited Overview Paper. 11 pp. cigr-
ejournal.tamu.edu


Билл Стаут,
Факультет биологической и сельскохозяйственной инженерии
Техасский сельскохозяйственный и машиностроительный университет, США
Карл Рениус
Факультет машиностроения, Мюнхенский технический университет, Германия
Джон Шулер
Факультет машиностроения, Университет штата Флорида, США

ПРОИЗВОДСТВО СЕЛЬСКОХОЗЯЙСТВЕННОЙ ТЕХНИКИ
И ЕГО АКТИВИЗАЦИЯ В МЕНЕЕ РАЗВИТЫХ СТРАНАХ

Резюме

Механизированное сельское хозяйство – это реальность! Ручные орудия, маши-
ны, приводимые в движение тяговыми животными, и трактора применяются в каждой
стране. Сельскохозяйственные инженеры и инженеры-механики востребованы для кон-
струирования эффективного оборудования или для выбора соответствующего размера
и типа машин для местных условий.
Глобальное производство сельскохозяйственной техники обсуждается наряду с
созданием совместных предприятий и другими совместными усилиями с производите-
лями.
Представлены некоторые принципы глобального развития тракторостроения.
Определены пять технических уровней в зависимости от мощности двигателя, типа
трансмиссии, гидравлических и электронных систем и т.д.


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Включен раздел о снижении производственных затрат с особым акцентом на
системный подход, сближающий многие виды специальных знаний для ускорения ин-
женерно-технического прогресса и снижения затрат.
Подчеркивается критическая необходимость в высокообразованных инженерах-
практиках и механиках сельского хозяйства. Этот тип высококвалифицированных кад-
ров потерян во многих университетах США и других странах мира. Не допустите, что-
бы это случилось в России!
Наконец, обсуждается необходимость участия сельскохозяйственных инжене-
ров-механиков в качестве ключевых фигур в междисциплинарных коллективах. Очень
часто мы концентрируем слишком много внимания на микро-исследованиях и не видим
общей картины – то есть ключевых проблем, которые стоят перед сельским хозяйст-
вом, таких, как задача накормить все возрастающее население планеты, совершенство-
вание распределениях доходов, чтобы все люди имели покупательную возможность
позволить себе сбалансированные и питательные продукты, сохранение и использова-
ние природных ресурсов, охрана окружающей среды, включая качество воздушной и
водной среды, и так далее. Механизация сельского хозяйства должна рассматриваться в
контексте этих широких проблем.

Получено 12.04.2005.



Д.С. Стребков, академик Россельхозакадемии, д-р техн. наук, профессор
Всероссийский научно-исследовательский институт
электрификации сельского хозяйства (ВИЭСХ), Москва

СОЛНЕЧНАЯ ЭНЕРГЕТИКА: СОСТОЯНИЕ И БУДУЩЕЕ РАЗВИТИЕ

Рассмотрены важнейшие факторы, материалы и технологии, определяющие роль
солнечной энергии в будущем производстве энергии. Ключевые факторы включают
эффективность преобразования солнечной энергии не менее 20%, возможность произ-
водства электроэнергии 24 часа в сутки, 50 лет срок службы энергетической системы,
цену 1000 американских долларов за киловатт пиковой мощности, доступность и низ-
кая цена материалов для солнечной электростанции и экологическая безопасность про-
изводства и работы солнечной электростанции.
Новые принципы преобразования солнечной энергии, новые технологии солнеч-
ного кремния, производства солнечных элементов, герметизации солнечных модулей,
использование стационарных солнечных концентраторов и новых методов передачи
электрической энергии для глобальной солнечной энергосистемы обеспечат к концу
столетия 60 -90% долю солнечной энергии в мировом производстве энергии.

ВВЕДЕНИЕ
Ресурсы солнечной энергии огромны и доступны каждой стране. Количество
солнечной энергии, поступающей на территорию России за неделю, превышает энер-
гию всех российских запасов нефти, газа, угля и урана. В России и Европе доля солнеч-
ной энергии в виде биомассы и гидроэнергии составляет 6% в общем производстве
энергии, в развивающихся странах 80% [1]. По терминологии, принятой в ООН, все

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