**¹3(52), 2013**

**SUMMARIES**

research of operational characteristics of
crank-piston mechanism of applied in oil and gas pipe - lines pumps. **N.
Davitashvili, V. Bakhshaliev****, V. Abaishvili****. “**Problems
of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 5-25, (Engl.).

Is
stated a study of influence of operational characteristics (friction,
clearance, wear) of crank-piston mechanism with clearances on the laws of
motion, velocity, and acceleration of the crank, rocker and piston of
mechanism. With the application of computer technology is given an analysis of
the operational characteristics of ideal and real mechanisms with application
of differential equations of basic and additional motions of mechanism
(contact-contact, contact break, break-contact and break-break). The numerical
methods for solving the problem of dynamic analysis of mechanisms are
considered. The effect of operational characteristics on the motion of
kinematic pair’s elements on the change of reaction forces and the laws of
crank motion are revealed.

The
carried out studies gives the possibility with taking into account of friction
to determine and select (establish) the optimum clearance dimensions conducive
to reliable and durable operation of piston pump and their mechanisms. 11 ill. Bibl. 17.
Engl.; sum. in Russian.

dynamical analysis of crank-piston mechanism with
consideration of impacts in kinematic pairs with clearances. **N.
Davitashvili, V. Bakhshaliev, V. Abaishvili.
“**Problems
of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 26-44, (Engl.).

Is
stated the dynamic investigation of crank-piston mechanism with taking into
account of impacts in kinematic pairs with clearances. Are defined the
velocities of colliding masses of links before and after impact and restoring
coefficients. In order for assessment of changes in vectors components are
applied the following hypotheses: Newton, on absolute smoothness of colliding
links, on instantaneous and dry friction ratio. Is determined that with
increasing of restoring coefficient the values of reaction forces and numbers
of chain interruptions are decreasing. The changes in dependency of values of
clearances are revealed. The results for
selection of optimal clearances providing the reliable and durable operation of
a piston machines, as well as their mechanism are given. 11 ill. Bibl. 23.
Engl.; sum. in Russian.

DEFINITION OF
DEFORMATION RATE IN THE HELICAL
PIERSING OF BILLETS. **T. Natriashvili, S. Mebonia, M. Mikautadze.
“**Problems of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 45-48, (Engl.).

In
article** **the formulas for calculating
the rate of deformation in the helical piercing
of tube billets in the hollow on mills with barrel rolls is proposed. Analysis of the formulas show that the rate of deformation is dependent on
the geometric and kinematic parameters of the rolling process. 2 ill. Bibl. 3.
Engl.; sum. In Russian.

THE MATHEMATICAL MODELING OF PLASMA-ARC CUTTING
PROCESS.** A. Tvalchrelidze, ****P****. ****Kipiani****, ****K****. Tskhakaia.
“**Problems of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 49-54,
(Engl.).** **

Based
on the fundamental laws of conservation, there is
developed the mathematical model of stationary process of plasma-arc cutting in
a first approximation. On the basis of this model, there are carried the
computational experiments the results of which fit well with the known
experimental data. There is observed a
significant impact of screening action of liquid metal film on cutting process.
3 ill. Bibl. 4. Engl.; sum. in Russian.

GENERATION
OF ENERGY FROM EQUILIBRIUM ENVIRONMENT – THE ABILITY RELEVANCE AND PROSPECTS.**
A. Aptsiauri. “**Problems of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 55-59,
(Engl.).

In the
article is shown that if in the thermodynamic cycle is carried out the
heat-insulated process of apparent cooling, with heat absorption in energy of
perturbations, and the reverse process occurs in conditions of perturbation
synchronization, such thermodynamic cycle would continuously generate usable
energy from the heat. As an example, is stated that in water flow, at
occurrence of turbulence and cavitation, it appears possibility of useful energy
generation.* *1 ill. Bibl.
7. Engl.; sum. in Russian.

CONTROL OF 3-DOF PLANAR PARALLEL ROBOT. **Vo Dinh Tung, S. Kheylo, V. Glazunov. “**Problems
of Mechanics”. Tbilisi, 2013, ¹ 3(52), pp. 60-64, (Engl.).

This paper deals with control of 3-DOF planer parallel
robot. The control algorithm of parallel robot
satisfying partial decoupling between translation and orientation degrees of
freedom is synthesized. Simulation result of control algorithm in desired
trajectory of end-effector of robot is shown. Here parallel manipulator control algorithm while
intersecting singular zones is considered. 12 ill. Bibl. 5. Engl. sum.; in
Russian.

CONTROL OF
MOBILE ROBOT BY MEANS OF CELL PHONE. **V. Margvelashvili,
R. Partckhaladze, M. Ben Chaim. **“Problems
of Mechanics”, Tbilisi, 2013, ¹
3(52), pp. 65-67, (Engl.).

In
article the new method
of remote control of terrestrial robotic vehicles is suggested. The method is
based on a on the cell phone applications for the movement control problems. It
shown that all necessary control operations can be easily done by means of
simple pressing on the cell phone buttons, and that the circuit remote control
is quite simple and does not require the development of complex knots. Also the
suggested method provides the wide working range of control (it is as large as
the coverage area of a cellular communications provider) and elimination of
influence of the outer transmitters. Bibl.3. Engl.; sum. in Russian.