Constructive redundancy C
S
shows how much of the total number of
elements in the mechatronic module are additional structural elements. It is
determined by the dependence:
Where
N
D
is the number of additional structural elements in the mechatronic
module;
N
0
is number of basic functional constructive elements in the mecha-
tronic module.
In a structural block there can be several elements that perform the same
functional transformation. For example, several different motion transducers
(transmissions) can be used simultaneously to obtain the required gear ratio.
From the point of view of the structure, only one functional motion converter
is sufficient in the block, the others are redundant, serving to change any of its
parameters (for example, transferring motion between elements that are remote
from one another, providing the necessary gear ratio, etc.). Therefore, they can
be attributed to additional structural elements.
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CHAPTER 4. BASICS OF DESIGNING OF
MECHATRONIC MODULES
4.1 General provisions of designing
Designing is a logical thought process where intuition, creativity, art, the
ability to work purposefully creatively, linking the achievements of science,
accumulated experience, forecasting prospects, production possibilities are
combined; this is one of the empirical-intuitive forms of creative activity, which
is difficult to study, formalize, and algorithmize; this is a long, time-consuming
process that requires a large material cost, which can be carried out at a high
technical level, if the designer takes possession of the design methodology,
will accumulate a large and industry-specific design experience; this is a set of
works aimed at finding, researching, calculating and developing design docu-
mentation for the design object [2].
In this tutorial, the mechatronic module is the object of construction. The
aim of the designing is to create a mechatronic module that meets the cus-
tomer’s requirements.
The task of designing is to develop a mechatronic module that ensures opti-
mal performance of the functional movement of the output link.
The need for construction arises after describing a certain set of consumer
properties that must an object of designing possess. These properties are the
input of the designing process, the output is the design documentation, accor-
ding to which you can make an object that satisfies these properties.
Designing involves three main strategies: analysis, synthesis and evaluation,
i.e. «the dismemberment of the problem into pieces», «joining the parts in a
new way» and «studying the consequences from the practical introduction of
a new product.» These stages can be repeated many times during construction,
each subsequent cycle differs from the previous one by greater detail and less
generality.
One of the main tasks in designing mechatronic modules is to increase
the efficiency of the design process. The construction of modern modules is
based on the transfer functional load from mechanical devices to intellectual
(electronic, computer and information) components. Such an approach in the
designing called mechatronic.
It dictates new requirements for elements of different physical nature that
are part of mechatronic modules, which, in its turn, leads to the development of
new technologies and design solutions.
The concept of integrated design allows achieving qualitatively new
characteristics of mechatronic modulesfor the synergetic integration of various
elements in a single body on the basis of modern scientific and technical know-
209
ledge in the field of design, manufacturing techniques and module control. At
the same time, it is necessary not only to unite individual parts into the system
using standard connections, but to make constructive links in the mechatronic
module inseparable and interpenetrating, and also to ensure the conversion
of information about the program of the module’s output to its purposeful
movement.
Integration of elements of different physical nature in mechatronic modules
allows to move to a higher qualitative level of performance of the main technical
indicators – speed and accuracy of movement of the output link, as well as to
ensure the compactness of the structure and its ability to quickly reconfigure.
What does interfere with herein a designer?
• force of habit (new problems are solved by old methods);
• narrowly practical approach (instead of a thorough consideration, the
designer immediately takes up the task);
• lack of flexibility of thinking (a paper clipcanbe usedonthe directsetting,as
wellasa hook and hole punch);
• excessive specialization (it is necessaryto extend the knowledge in diffe-
rent areas);
• fear of criticism;
• influence of opinion of authorities.
Some provisions for the construction of mechatronic module [10]:
• the development of the project goes from general to specific, and not vice
versa. This is due to the terms of reference;
• new technical solutions appear as a result of a gradual approach to the
goal;
• the most rational solution is achieved as a result of the development of a
large number of options and their in-depth analysis;
• in searching for a solution, the requirement of correctness of functioning
prevails over other requirements (structural organization, constructive
solution, efficiency);
• design parameters of elements of the mechatronic module are determined
as a result of engineering calculations;
• the design of the mechatronic module is performed taking into account
the possibility and laboriousness of its manufacture, operation and repair;
• the process of designing from the origin of the idea to the drawing up
of working drawings is carried out taking into account the so-called
«trifles» (for example, whether it is necessary to provide for details cham-
fers, which to choose the landing, etc.).
• the economic evaluation of the designing the mechatronic module can be
made only after the appearance of its variant meeting the requirements of
functioning.
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