Stepper Motors

With high speed of technology development, Plasma CNC machine plays an important role in industry, as it can cut any metal using only compressed air ignited at high voltage and high frequency. The cut is fast, clean and highly accurate. This report shows how plasma CNC machine was built step by step. Plasma CNC machine contains several parts: plasma unit, controller circuit, CNC table and software. Plasma unit generates the plasma torch which can cut the metals. Controller circuit controls the stepper motors using microstepping method. This method has high accuracy control. CNC table design and analysis was performed by Autodesk Inventor software. CNC table contains three axes Y-axis, X-axis, Z-axis which move using rods and rails as linear motion system. It is strong and stable. Plasma trace Software was used to convert images to G-code that will be loaded to MACH3 software and mach3 will send commands to controller circuit by parallel port to move the axes. The plasma CNC machine was tested and gave good results with high accuracy.

Resumen Este documento reporta los procesos que se desarrollaron para la creación de un registrador concéntrico. La práctica incluye el uso de motores a pasos como los actuadores principales, así como el empleamiento de la tarjeta de desarrollo Arduino UNO para el control del instrumento completo. En este reporte se incluye información acerca de la metodología utilizada, se plantea la problemática, se especifica el funcionamiento de los componentes del sistema y se presentan los resultados mediante capturas del propio registrador.

This research paper describes the automated toll
collection system for toll gate based on RFID technology. Most
of the toll collection systems commonly used in Myanmar is
manual transaction. Nowadays, streams of traffic are increased
and toll gate on highways are congested. It will cause the traffic
jam and waste time. The objective of this journal paper is to
transform manual transaction to automated toll collection with
the help of RFID technology. There are three portions in toll
collection system. They are RFID system, balance deduction
system in host computer and toll  gate control system. For the
RFID system, 13.56 MHz passive RFID reader and tag pairs are
used.

The need for a robotic arm is increasing in areas such as food industries, consumer goods manufacturing industries,
plastic goods manufacturing industries and electronics industries. However, it is still more concentrated in automotive
industries. For a robotic arm to perform human tasks, it not only needs to have the arm like form but also features like accurate
motion, proper communication and even intelligence. Although the usage of robotic arm is a difficult task for a layman i.e. only
a learned person can operate it. Through our project, we propose its usage for household applications, for students to do
simulations, etc. Using our robotic arm prototype people can do household chores and learn its operations and working day by
day. Also students can learn its programming and kinematics and also upgrade accordingly. It has numerous software and
hardware interactions and expansion interfaces in order to maximize the student’s freedom to create. Through building, students
can learn how a robotic arm and its mechanics work.

Este trabajo presenta los resultados de reparar un equipo didáctico CNC obsoleto e inoperante, bajo la idea de utilizar materiales de bajo costo y un software actual, ofreciendo la opción de comunicarse a través de un puerto que sea de uso generalizado como en su tiempo lo fue el puerto paralelo. Comenzando un poco de historia y conceptos de los sistemas CNC para demostrar la importancia de conocer y saber operarlos, el papel de la electrónica e informática en la mejora de estos equipos, la descripción del problema, métodos y materiales, análisis de resultados, así como conclusiones y trabajos futuros.

Mathematical models for step motors have been in existence for several years. In this paper, a technique for modeling the effects of the drive circuit is presented. The Kuo-Singh model for the permanent magnet step motor, with flux linkages as state variables, is generalized to allow independent control of the motor phase resistances which allows for improved modeling of the non-linear characteristics of typical drive circuits, such as chopper drives.

This study deals with mid-frequency resonance (MFR) in the variable-reluctance (VR) step motor. If an incremental position encoder is used to provide feedback to control the switch angle of the motor, MFR is eliminated. The present study shows that a similar result is possible using velocity information extracted from the current waveforms of the motor for use as feedback.

This paper presents MOSFET based analog to digital converter which is simple in design, has high resolution, and conversion rate better than dual slope ADC. It has no DAC which will limit the performance, no error in conversion, can operate for wide range of inputs and never become unstable. One of the industrial applications, where the proposed high resolution MOSFET ADC can be used is, for the positioning of control valves in a multi channel data acquisition and control system (DACS), using stepper motors as actuators of control valves. It is observed that in a DACS having ten control valves, 0.02% of positional accuracy of control valves can be achieved with the data update period of 250ms and with stepper motors of maximum pulse rate 20 Kpulses per sec. and minimum pulse width of 2.5 µsec. The reported accuracy so far by other authors is 0.2%, with update period of 255 ms and with 8 bit DAC. The accuracy in the proposed configuration is limited by the available precision stepper motor and not by the MOSFET based ADC.