Posts

Showing posts from June, 2018

Varijabilni frekvencijski generator pravougaonog signala sa impulsno širinskom modulacijom

Image
UVOD
VF drajver je varijabilni frekvencijski generator pravougaonog signala sa impulsno širinskom modulacijom. Jedna od primena je regulacija obrtnog momenta i brzine DC motora, što je i bio cilj izrade VF drajvera. Članak prikazuje praktičnu realizaciju, uz prateće video klipove koji prikazuju način funkcionisanja i probleme koji se rešavaju VF drajverima. VF drajver je baziran na Texas Instruments TL074 operacionom pojačavaču, te shodno tome članak opisuje način odabira odgovarajućeg operacionog pojačavača kako bi se ispunili frekvencijski zahtevi.
Podešavajući VF drajver potreba i primena
Pre nego što započnemo raspravu na temu VF drajver-a ili ti VF kontrolera (VF – variable frequency, prevod: promenljiva frekvencija) treba postaviti pitanja: šta je VF drajver, koja je potreba za istim i za šta se primenjuje? VF drajver je generator pravougaonog signala uz primenu impulsno širinske modulacije (ili PWM modulacija), sa mogućnošću podešavanja frekvencijskog opsega na skalama označenim u…

A finite state automat - Injecting behavior into the system, Part II

Image
Injecting behavior into the system
Introduction In the last issue of the magazine, we introduced the idea/method of injection system behavior of the finite automat system and defined three basic components which consist of: generic finite automat, state definition and transition matrix. In this issue, we continue with the topic, whereby we will be introduced to different aspects of application, principles, code portability and practical problems in implementation. Principles and concepts Programmable autonomous vehicles (in the text below PAV) are one section of of application, but the method can be used for different purposes. Let's return first to the high level of PAV architecture, the reason for this will be clear soon. PAV is made up of: control units (in our case 8051 microcontroller, although generally this can be any digital computer), power amplifier (device driver), actuator (DC motors in our case) and set of sensors that make feedback back to control unit (InfoElektronika …

A finite state automat - Injecting behavior into the system, Part I

Image
Injecting behavior into the system Introduction A finite state automat as a general model for describing the behavior of the system has wide application. One of the fields of application is shown in the last issue of the magazine (# 112) and refers to the description of the behavior of a programmable autonomous vehicle. However, the presented software solutions have certain drawbacks - each new task entails reprogramming. Injection System Behavior is the method/idea to describe the behavior of the system at an abstract level using the generic structure of the finite automat, eliminating reprogramming.  Injecting behavior into the system In the previous two issue of the magazines (InfoElektronika # 111 and # 112) are displayed two different tasks, two different software solutions, executed by a programmable autonomous vehicle (hereinafter referred to as PAV): avoiding the obstacle and defined movement of the black path. Both tasks are modeled by a automat with a finite state number (herein…