Figure 2.6 – Вlock diagram of the mechanism 192

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CHAPTER 3. INTEGRATION IN 
MECHATRON MODULES
3.1 Models of mechatronic modules
The design of the mechatronic module begins with the construction of 
its functional model, which is obtained after the functional analysis of the 
technical assignment data. First of all, the designer should highlight the main 
functions, which in the end should be implemented by the module in relation 
to external objects. Such functions can be: the speed of the output link, the 
amount of torque or force on it, the transmission of a certain type of signal 
to external devices that interact with the module during its operation, etc. At 
this stage, the system can be represented in the form of a «black box» with 
a set of inputs, outputs and external disturbing influences. Then internal 
functional transformations are introduced into the functional model of the 
mechatronic module, which allow transforming a set of input actions into 
output with a given set of parameters. At this design stage, it is important to 
decide which additional feedbacks are necessary for the high-quality operation 
of the mechatronic module, i.e. to assess its current internal state and adjust the 
functional movement of the output link.
Thus, the functional model of the mechatronic module should give a 
complete idea of the transformation of the motion program specified by the 
computer control device into a purposeful controlled movement of the output 
link interacting with the objects of the external environment.
The functional model is usually represented as a circuit consisting of blocks 
of rectangular shape and arrows connecting these blocks. In this case, the 
blocks indicate the transformations themselves, and the arrows specify their 
sequence. We shall compose functional models of different types of mecha-
tronic modules. The functional model of the motion module is shown in Fig. 
3.1, of the mechanic mode of motion in Fig. 3.2 and the intelligent mechatronic 
module in Fig. 3.3
Figure 3.1

193
Figure 3.2
Figure 3.3
After compiling the functional model, the designer decides which hardware 
can effectively implement the resulting functional model, i.e. conduct a fun-
ctional-structural analysis. The result of this work is the structural model of the 
mechatronic module.
This model is shown graphically as well as the functional model in the 
form of rectangular blocks and arrows. Only in this case, the building blocks 
represent individual hardware parts of the mechatronic module, i.e. the devices 
that make up its structure, and the arrows represent interblock communications. 
For electromechanical mechatronic modules, the blocks can be:
• computer control unit (CCU) of motion, the functional task of which 
is information transformation (digital signal processing, digital control, 
calculation of control actions, data exchange with peripheral devices);
• digital-to-analog converter (DAC), which realizes the function of 
information-electric converter;

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• power converter (PC) is usually consisting of a power amplifier, pulse 
width modulator (PWM) and a three-phase inverter (for asynchronous 
motors), amplifies the electrical signal;
• controlled electric motor (CEM) (alternating or direct current), which is 
an electrical element, performs the conversion of electrical energy into 
mechanical transforms electrical energy into mechanical;
• mechanical converter (MC), realizes a given controlled motion and 
interacts with external objects. In the drive modules, such converters 
are used as motion transducers, reducers, variators, or directly use the 
operating element (for example, in mechatronic motor-spindle modules);
• feed back device (FBD), which is used to monitor current voltages and 
currents in the power converter, as well as control functions (for example, 
for organizing the torque control loop developed by the module);
• information devices (ID) are feedback sensors (FBS) and electronic units 
for processing and converting signals used to determine the position and 
speed of the output link of the mechatronic module.
To connect the blocks use interfaces that are represented as circles with 
the inscription alongside them, I1, I2 ... They have a different physical nature, 
which depends on the type of structural blocks they connect.
The structural model should give a complete idea of what elements the 
mechatronic module consists of and what links between them.
Depending on the physical nature of the input and output variables, the 
interface blocks can be either mechanical (example, couplings), and electronic. 
Their design, manufacturing and commissioning create serious problems for 
developers. Therefore, in the mechatronic modules they tend to reduce them 
and, ideally, to complete destruction. This can be achieved with a high degree 
of integration of elements of the mechatronic module at the stage of its design.
Comparing the functional and structural models of the mechatronic module, 
it can be seen that the total number of basic and interface blocks in the struc-
ture of the model significantly exceeds the number of necessary functional 
transformations, i.e. there is structural redundancy. 
The presence of redundant blocks leads to a decrease in the reliability and 
accuracy of the mechatronic module, the deterioration of its mass-dimensions. 
Therefore, it is necessary to strive to reduce the number of structural blocks 
in the structure of the mechatronic module, to implement the specified fun-
ctional transformations with a minimum number of structural and structural 
elements, combining two or more elements into single multifunctional modules, 
redistributing the functional load from the hardware blocks to the intellectual 
(electronic and computer) components. However, it is not always possible to 
select the structural model of the mechatronic module from its functional 

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model unambiguously. In the actual design process, the designer faces an 
important task of working out several possible options for structural realization 
of the model and choosing the best solution. After carrying out the functional 
structural analysis and selection of the structural model of the mechatronic 
module, its structural and constructive analysis is conducted to create a con-
structive model.
Structural-constructive analysis is to select the types and number of basic 
and additional, if it is necessary, structural elements entered into the composi-
tion of the mechatronic module to ensure its high performance, reliability, 
durability, accuracy, etc.
The main structural elements of the mechatronic module can be: a device, 
computer control, digital-to-analog converter, a controller, power converter, 
motor, a mechanical transducer, sensors, feedback sensors, feedback device etc. 
for more additional mechanical elements included in the mechanical converter, 
mechatronic module: braking, safety, leftovers, damping device, guides, etc.
They allow, for example, to stop the output link in the right place, to protect 
the mechatronic module from overload, to choose backlash, etc. 
As the result is a constructive model of mechatronic module, which gives a 
complete picture of the number, type, arrangement, and interaction of the main 
and additional structural elements in the mechatronic module. 

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