Mechatronic systems in automation engineering

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To perform technological processes on the RTC, it is possible to include 
a roller conveyor and a pallet feed mechanism with workpieces, as well as a 
rotary table with latches. Technological equipment of RTC is provided with 
pneumatic power supply at a pressure of 0.5 MPa. As a working body, a special 
pneumatic head (produced by Nokia, Finland) is used, which is fixed to the 
external flange of the torque-sensitive sensor (Figure 6.5).
Figure
 6.5 – Robotic technological complex of machining based on the robot PM-01:
1 – manipulator «PUMA-560»; 2 – control device «Sphere-36»; 3 – working body; 
4 – computer upper level control; 5 – force-torque device sensitization; 
6 – technological table.
Figure 6.6 – The working body of the robot with a force transducer

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The main technical characteristics of the pneumatic head: power 160 W, 
the speed of the output shaft 28000 min
-1
, weight 1.5 kg. Electromechanical 
manipulator «PUMA-560» of anthropomorphic type has 6 rotational degrees of 
mobility. Load capacity of the robot is 2.5 kg, positioning accuracy is 0.1 mm. 
The control device «Sphere» is intended for position and contour control 
of the manipulator’s movements. The system is multi-processor and two-level: 
it contains a central processor and six processor drives.The modules of the 
device have unified internal communication buses (Q-BUS type) and a standard 
communication interface with technological equipment.
The device force-torque implementation (DFTI) consists of two functional 
modules: the force sensor and processing unit of force information. The force 
sensor designed in the form of flat cruciform plates, on the edges of which are 
glued strain gauges.
The sensor design provides for the measurement of three components of the 
force vector acting on the robot body: a force perpendicular to the force sensor 
flange (Fz) and two moments in the flange plane (Mx and My). As sensitive 
elements, we use foil strain gages of the type KF 5P1-3200-A12. The sensor is 
made of an aluminum alloy D16-T, which has a high Young’s modulus and a 
low specific gravity.
The processing unit of the force-moment information is intended for conver-
ting signals from the amplifier into three information signals about vector of 
forces acting on the working body. The unit is made in the form of a separate 
board and installed in the body of the strain gauge.
Technical characteristics of the device of a torque-sensitive sensing:
– number of measured components of the force vector – 3 (axial load up 
to 50 N, transverse forces along the X and Y axes to 25 N on the arm 
0.12 m);
– a range of output signals for inputting into the computer from –5 V to +5 
V, for inputting into the «Sphere-36» from 0 to + 5 V; 
– the error of the output signal is not more than 2% of the nominal value.
When controlling the robot in machining operations, the main function 
of the computer is to process the signals from the torque-sensing sensor and 
generate motion correction signals. If the force and torque sensor contains an 
integrated microprocessor, then the organization of information exchange with 
the computer is not difficult. Otherwise, you must use a multifunction adapter 
(MA), which reconciles the analog and digital signals with the system bus of 
the computer.
The adapter contains the following functional nodes: analog-a-digital 
converter with an input switch, a digital-to-analog converter, a parallel input-
output device, and a timer. The serial set of the control device «Sphere-36» 

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does not have the ability to enter and process analog information; therefore, on 
the basis of the standard analog input module (AIM) of this control cabinet, an 
analog input controller was implemented from the torque sensor.
Six channels of the AIМ serve for inputting signals from potentiometric 
sensors located in the degrees of mobility of the manipulator. The remaining 
two ADC channels, which are used in normal mode for system testing, are 
switched to communication with external signal generators. Communication 
between the «Sphere» control device and the computer is provided by special 
drivers. 
The programming of movements of the technological robot is carried out 
with the help of a specially developed complex for the preparation of control 
programs (Figure 6.7).
Figure 6.7 – System of automated programming of technological robot movements

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Thus, this robot technology complex machining realizes the modern concept 
of building production systems such as CAD/CAM, when computer-aided 
design of the product and its automatic manufacturing in a single system and 
the user’s task consists only in preparing the initial computer model of the part.
This approach has the following main advantages:
– reduces the changeover time of the robot in comparison with the training 
mode; 
– uses a single programming environment, if it is possible to program seve-
ral robots at one working place;
– provide preliminary validation logic of the robot, analyzing its behavior 
in disaster and emergency situations; 
– the human operator is derived from a potentially hazardous working 
area;
– the system of robot programming integration with databases CAP; 
CAPR;
– through the use of high-level languages makes possible the preparation 
of structured programs, optimizing movements of the robot according to 
different criteria.
The composition of the developed system of the automated programming 
includes four main components: geometric modeling subsystem, simulation 
subsystem of the dynamic system, the robot is working on-a tool-a workflow 
engine programming and optimization of trajectories for robot technology, the 
database technology. 
To start the programme must be bound coordinate system by setting the 
mode of distance learning reference point in the robot’s workspace. Then there 
is the automatic execution of functional movements, while the cutting force is 
maintained at a predetermined level by regulating a contour of the speed of the 
working body.

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