Acknowledgement

The students wish to express their heartfelt thanks and gratitude to all the people who

extend their thoughts and time and efforts in the realization and completion of the project.

To their friends and relatives, who in one way or another unselfishly extended their

lenient hands, time motivation and efforts in directing them to work hard and strive more to

develop the system.

To their adviser, Engr. Wilson R. Duldulao for his extraordinary guidance and

encouragement.

To their beloved parents and guardians, who have and provide a lot of the needs

especially moral and financial support towards the success of the project.

To the Almighty God, for His infinite Grace which helped them through their challenges.

For the Fortitude and Wisdom in the completion of the project.

Introduction

A DC motor is any of a class of electrical machine that converts directly direct current

Electrical power into Mechanical power. The most common types rely on the forces produced by

magnetic fields. Nearly all types of DC motors have some internal mechanism, either

electromechanical or electronic to periodically change the direction of current flow in part of the

motor. Most types produce rotary motion; a linear directly produces force and motion in a

straight line.

DC motors were the first type widely used, since they could be powered from existing

direct-current lighting power distribution systems. A DC motor’s speed can be controlled over a

wide range, using either a variable supply voltage or by changing the strength of the current in

the field windings.

Small DC motors are used in tools, toys and appliances. The universal motor can operate

on direct current but it is lightweight motor used for portable power tools and appliances. Larger

DC motors are used in propulsion of electric vehicles, elevator and hosts or in drives for steel

rolling mills. The advent of power electronics has made replacement of DC motors with AC

motors possible in many applications.

In establishing in efficient switching circuit, relays are one of the most efficient choice. A

relay is an electromagnetic switch operated by a relatively small electric current that can turn on

or off a much larger electric current. The heart of a relay is an electromagnet. A relay is some

kind of electronic lever, switch it on with a tiny current and it switches on another appliance

using a much bigger current. This is useful because many sensors are incredibly sensitive pieces

of electronic equipment and produce only small electric currents. But often, they are needed to

drive bigger pieces of apparatus that use bigger currents. Relays bridge the gap, making the

system produce only small electric currents to activate larger ones.

Meanwhile in sensor technology, a Photosensor and LDR are very common. AN infrared

(IR) Sensor is used to detect obstacles in front of the robot or to differentiate between colors

depending on the configuration of the sensor.

An IR Sensor consists of an Emitter, Detector and Associated Circuitry. This circuit

required to make an IR Sensor consists of two parts; The Emitter circuit and the receiver circuit.

The Emitter is simply an IR Light Emitting Diode and the detector and associated

circuitry is simply and IR Photodiode which is sensitive to IR Light of the same wavelength as

that emitted by the IR LED. When the IR light falls on the Photodiode, its resistance and

correspondingly its output voltage, change in proportion to the magnitude of the IR Light

Received. This is the underlying principle of working of the IR Sensor. IR Sensors are also used

to distinguish between black and white surfaces.

A transmission medium is required for infrared transmission which can be comprised of a

vacuum, the atmosphere or an optical fiber.

Importance of DC Motors

The main reason is the motor’s variable speed behavior. When the voltage applied to the

armature of a DC Motor increases, the motor’s speed increases correspondingly.

Another reason is the DC Motor can develop full torque from zero up to its base speed.

This constant torque characteristic allows the DC motor to be used as conveyor belts, elevators,

cranes, extrudes and mixers, amongst others. The full torque from zero speed is useful when the

application needs to be stopped when full loaded and got moving again.

Principles and Operation of DC Motors

A simple DC Motor have stationary sets of magnets in the stator and an armature with

one more winding of insulated wire wrapped around a soft iron core that concentrates the

magnetic field. The windings usually have multiple turns around the core and in large motors

there can be several parallel current paths. The ends of the wire winding are connected to a

Commutator. The Commutator allows each armature coil to be energized in turn and connects

the rotating coils with the external power supply through brushes. Brushless DC Motors have

electronics that switch the DC Current to each coil ON and OFF and have no brushes.

The total amount of current sent to the coil, the coil’s size and what it’s wrapped around

dictate the strength of the electromagnetic field.

The sequence of turning a particular coil on or off dictates what direction the Effective

Electromagnetic Fields are connected or pointed. By turning ON and OFF coils in sequence a

rotating magnetic field can be created. These rotating magnetic fields interact with the magnetic

fields of the magnets in the stationary part of the motor (Stator) to create a force on the armature

which causes it to rotate. In some DC motor designs the stator fields use Electromagnets to

create their magnetic fields which allow greater control over the motor at high power levels, DC

motors are almost always cooled using forced air.

Objectives

1. To design and construct a system for the students to use to their respective experiments.

2. Describe the variable outputs of the direct current motor using a transducer.

3. Recognize the basic principle, setup, properties of the DC motor, ICs, Relays and

Sensors.

4. Determine the different uses of the system or module.

5. Present data that satisfies the principles and properties of the DC Motor module.

6. Present applications using the principle of DC Motor.

Materials

A. DC Motor Driver Components

R1,R6

R2, R3, R4, R5

RF

C1, C2

C3

C4

IC1

IC2

IC3

IC4

T1

T2

POTENTIOMETER

MOTOR

1K Ω Resistor

2.2K Ω Resistor

220K Ω Resistor

0.01 µF

520 µF

0.1 µF

LM555N

UA741P

HD74HC00P

L293D

2H3906

2N222

10K

B. Relay Switch Components

DPOT Relay 12V

C. Sensor Components

R1, R2, R4

R3 Potentiometer

IC1

IR1 D1

IR2 LED

1K Ω Resistor

10 K Ω Resistor

LM324

Manual

Parts

1. DC Motor

2. Main Switch

3. Start

4. Stop

5. Revers

6. Speed

7. Infrared Sensor

Steps

1. Connect the Power Plug.

2. Turn on the Main Switch.

3. Press the Start Button to start the motor.

4. Adjust the Speed knob to maximize or minimize the rotation of the motor.

5. Reverse the rotation of the motor by pressing the forward or reverse button.

Observation

The DC Motor was quite a challenging motor to begin with. The researchers first strted to

research on the configurations of the IC’s they used and conducted experiments with the circuit

to develop a more efficient output of positive voltages.

In their experiments, they observed that some of the switching circuits are not compatible

with the DC Driver Motor, which made them decide to use another approach with a relay circuit.

Regarding with the sensor, they tried the Light Dependent Resistor technology using the

laser as a transmitter. The only drawback of this technology is the capacity of the LASER to

transmit light to be detected by the LDR is insufficient, thus making the output less likely to

produce large voltage drops.

The LDR was then replaced whit the help of the suggestion of Engr. Wilson Duldulao to

replace the LDR with Infrared. The Infrared sensor became more reliable than the LDR.

Conclusion

The DC Motor is one of the most important motors that is ever invented. It sparked a

great revolution in the whole industry and even changed the course of history. It made translating

mechanical force to electrical force possible. It is because of the DC Motor that green energy is

possible. We couldn’t imagine the world where in we are in without motors.

DC Motors are made for speed. Its general purpose is to convert Electrical force to

mechanical force which in return will be used in different applications. In the experiment we saw

how simple a DC Motor is yet how complex it is. The simple idea of a motor powered by the

simplest form of current which is DC, Yet can be transformed into different applications just by

connecting it to different circuits. The reliability of the Motor was beyond compare. It does what

you expect it to do almost all of the time.

The DC Motor being the ancestor of all known motors is here to stay. It won’t be

obsolete anytime soon because of its speed, reliability and its profound simplicity.