Modeling and simulation of machined surface layer microgeometry parameters

 The formation of the microtopography of the machined surface is one of the most critical factors in ensuring the effective operating properties of the product. These are indicators such as wear resistance, fatigue strength, provision of friction parameters of moving joints, etc. The most important reason for the formation of microroughness is vibration in the technological surface of the machine-tool-tool-tool-workpiece. This article is devoted to describing a new method of modelling the dynamic processes of machining.

The Modes of the Power Supply Scheme of Own Needs During Start-up of the Power Units With an Additional Working Transformer

The efficiency of operation of power units of powerful thermal and nuclear power plants is largely determined by the reliability of power supply systems for their own needs. The main requirements for such systems are maintaining the required voltage level on the busbars of the distribution charters of their own needs and reduction of the time of forced power outages. Ensuring these requirements by the Ukrainian energy sector is complicated by the fact that most of its power plants are operated for a long time, and their equipment is significantly worn out.

Research and simulation of the machining process of difficult-to-cut materials

Heat-resistant and high-alloy steels and alloys are difficult materials to machine. Optimizing the cutting parameters for such materials is a complex and multi-factorial technological process planning task. The paper describes the method of analysis of loading, thermodynamic and stress-strain state of a workpiece while cutting of typical representative of hard-to-cut materials (chromium-nickel alloy IN718) using finite element simulation. Influence of feed rate on cutting force and temperature in the zone of chip formation is given.

Universal mathematical model of asynchronous machine as an element microgrid in smart grid

An universal mathematical model of an induction machine (IM) has been constructed, taking into account the saturation of the main magnetic circuit of its magnetic core and the active power losses.  The proposed approach to IM modeling expands the abilities of MATLAB / Simulink environment for analysis of the electric power supply systems (microgrid in the smart grid) with the nonlinear elements and dynamic load in abnormal, asymmetric and fault regimes.

Modeling and control of an electromechanical system with a permanent magnet generator and a voltage source converter

In the paper simulation dynamic models for the analysis of characteristics and transients of electromechanical system using a permanent magnet electric generator (PMG) connected to a variable speed fixed pitch wind turbine (WT) and a voltage source converter (VSC) mathematical models are developed. The system supplies a direct current (dc) resistive load through a controlled switch.

Modelling and simulation of pneumatic system operation of mobile robot

Problem statement. Mobile robots are currently of significant interest among researchers and designers all over the world. One of the prospective drives of such robots is equipped by a pneumatically operated orthogonal system. The processes of development and improvement of orthogonal walking robots are significantly constrained because of the lack of an open-access comprehensive scientific and theoretical framework for calculating and designing of the energy-efficient and environmental-friendly pneumatic walking drives.

Design and operational peculiarities of four-degree-of-freedom double-legged robot with pneumatic drive and turning mechanism

Problem statement. Mobile robots are of significant interest among scientists and designers during the last several decades. One of the prospective drives of such robots is based on pneumatically operated walking (stepping) system with no use of electric, heat, magnetic or other types of energy. This allows the use of pneumatically-driven robots in the cases when the use of other energy sources is prohibited (e.g., in some gaseous or fluid mediums).

Implementation of Fpga-based Pseudo-random Words Generator

A hardware implementation of pseudo-random bit generator based on FPGA chips, which use the principle of reconfigurability that allows the modernization of their algorithms and on-line replacement of the internal structure (reconfiguration) in the process of functioning have been considered in the paper. Available DSP blocks embedded into the structure of FPGA chips allow efficient hardware implementation of the pseudorandom bit generator through the implementation of the basic operations of multiplication with accumulation on the gate level.

Structural and kinematic analysis of pantograph-type manipulator with three degrees of freedom

Problem statement. The processes of development and improvement of autonomous mobile robots are significantly constrained because of the lack of an open-access comprehensive scientific and theoretical framework for calculating and designing of autonomous mobile robotic systems Purpose. The main objective of the paper consists in carrying out kinematic analysis and motion simulation of pantograph-type manipulator with three degrees of freedom. Methodology.