Abstract
A microcontroller-Based Versatile Stepper Motor System/Trainer
has been designed and implemented in this project. The
developed prototype was built with readily available components
including the AT89C51 Microcontroller which runs the control
software and provides a flexible interface to the stepper motor
drive. The control system is capable of driving the stepper motor
clockwise or counterclockwise in full steps or in half steps
according to the need of the stepper motor driven application.
The angular displacement for the stepper motor shaft is 50 per
full-step and 2.50 per half-step but this varies according to the
design of each stepper motor. This prototype can be used to
demonstrate the features of a stepper motor that recommends it
for use in incremental motion control where precision and
positioning accuracy are of paramount importance. Examples of
such applications include its use in conveyor belts in
pharmaceutical industries, bottling companies, printers, and
INTRODUCTION
1.1 Background of the Study
Microcontroller based stepper motor control is an electronic
device which transfers control to an attached object and drives
it towards a particular direction in stipulated steps as specified
by the microcontroller, depending on control input signals from
the controller, the stepper motor can be caused to exhibit
various effects through specified mode of operation. It is
applied in electromechanical devices were precise or specific
angular movement is being addressed.
The project aim is to witness the application of stepper motor
on devices attached to it, there by experimenting the
movement with the help yielded by this motor. With the aid of
control input buttons, specific directive signals are being set up
to activate the stepper motor which now transfer control to
objects/device attached.
The experiments portrayed by this project are achieved using
the control software found in the microcontroller.
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1.2 Objective of the Project
The Objectives of this project are as follows,
? To design and implement a stepper motor controller
by programming the microcontroller with sequence
of actions to carry out as at when due
? To design and implement a stepper motor drive or
power circuit
? To design and develop stepper motor base
experiments to serve as laboratory work for students
of tertiary institution
? To interface the stepper motor controller to the
stepper motor drive using opto isolators to protect
digital circuits from power circuits
? To test the system by performing all the designed
experiments with it.
1.3 Justification of Project
The conventional motor (AC/DC) spin continuously, with the AC
motor having two parts which are the outside stationary stator
and an insider rotor while the stepper motor moves one step at
a time, if we command a stepper motor to move some specific
number of steps, it rotates incrementally that many number of
steps and stops. Because of this basic nature of a stepper
motor, it is widely used in low cost open loop position control
system. Open loop control means no feedback information on
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about the position is needed. This eliminates the need for
expensive sensing and feedback devices such as optical
encoders. In this project, the position is known simply by
keeping track of the number of input step pulses. This fact
simply entail that the aim of this project was actualized.
1.4 Scope of the Project
This project covers the theoretical and analytic concept behind
motors, its origin and advancements made in the technology.
The design of an electronic circuit that will help achieve the
desired objective will be shown in details.
Also discussed are the various components that will be
implemented in the circuit, the pin layout, the wiring
schematics and the complete schematics and packaging of the
project.
Moreover, the desired objectives were compared with the
actual outcome based on a set of test data, to determine how
satisfactory the project is, cost analysis shall also be taken into
consideration by looking at how much it takes to develop one
system. From this cost evaluation, one can then simulate cost
of mass producing the system. The problem encountered
during the development of the project and the steps taken to
overcome them shall be listed.
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1.5 Block Diagram Overview of the Project
Figure 1.1 represented the sequence followed in developing the
project.
Fig 1.1 Block Diagram of the Project
1.6 Project Report Organisation
This project report is organized into chapters and sections.
There are six chapters in all. Chapter one introduces the
project topics, and talks about the background, desired
objectives and justification of the project amongst other things.
Introduction
Design Implementation, testing and integration
Summary and conclusion
Literature review
System design
System analysis
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An overview of the previous works done in the use of
conventional motors and a full details about the use of stepper
motor with respect to various experiments are the subject of
chapter two. Chapter three gives an in-depth analysis of the
system and gives details on all the components used in
designing and building this project.
Chapter four covers the design specification,
hardware/software tradeoffs, the various interface including
output interface, input interface, control interface and power
supply.
Chapter five is all about the implementation of the design
generated in chapter four. It includes detailed pin layouts of
components and wiring schematics as well as the control
software implementation system packaging, testing and
integration, performance evaluation and cost analysis are also
treated in this chapter.
Finally, chapter six covers problem encountered during design
and implementation, the steps taken to overcome them,
summary of the project, and also suggestions for improvement
on the project