In this
part, we will discuss more about the components that are used in Development of
Integrated Crops Management System (DICM). The main components for this project
such as IR sensor, solenoid DC motor, DC gear motor, arduino and buzzer. This
part is to enhance the knowledge of the student about the project.
Infra red sensor (IR
sensor)
This sensor can be used
for most indoor applications where no important ambient light is present. For
simplicity, this sensor doesn't provide ambient light immunity, but a more
complicated, ambient light ignoring sensor should be discussed in a coming
article. However, this sensor can be used to measure the speed of object
moving at a very high speed, like in industry or in tachometers. In such
applications, ambient light ignoring sensor, which rely on sending 40 kHz
pulsed signals cannot be used because there are time gaps between the pulses
where the sensor is 'blind'...
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The solution
proposed doesn't contain any special components, like photo-diodes,
photo-transistors, or IR receiver ICs, only a couple if IR-LEDs, an Op amp, a
transistor and a couple of resistors. In need, as the title says, a standard IR
led is used for the purpose of detection. Due to that fact, the circuit is
extremely simple, and any novice electronics hobbyist can easily understand and
build it.
Figure
1: An infra red sensor
Solenoid DC motor
The Solenoids
Solenoids are actuators capable of linear motion. They can be
electromechanical (AC/DC), hydraulic, or pneumatic driven and all operating on
the same basic principles. Give it energy and it will produce a linear force.
They are great for pushing buttons, hitting keys on a piano, valve operators,
and even for jumping robots. DC solenoids operate on the same basic principles
as a DC motor
Figure 2: Solenoid DC motor
How solenoids
work
Inside a solenoid is motor wire coiled in a special way. When
an electric current was send through this wire (energized), a magnetic field is created. The inner shaft of a
solenoid is a piston like cylinder made of iron or steel, called the plunger or slug (equivalent to
an armature). The magnetic field then applies a force to this
plunger, either attracting or repelling it. When the magnetic field is turned
off, a spring then returns the plunger to its original state.
Figure 3: Inside of solenoid motor Figure 4: Effect of solenoid
motor
DC gear motor
A gear motor
is a type of electrical motor. Like all electrical motors, it uses the
magnetism induced by an electrical current to rotate a rotor that is connected
to a shaft. The energy transferred from the rotor to the shaft is then used to
power a connected device. In a gear motor, the energy output is used to turn a
series of gears in an integrated gear train.
Function
In a gear
motor, the magnetic current which can be produced by either permanent magnets
or electromagnets turns gears that are either in a gear reduction unit or in an
integrated gear box. A second shaft is connected to these gears. The result is
that the gears greatly increase the amount of torque the motor is capable of
producing while simultaneously slowing down the motor's output speed. The motor
will not need to draw as much current to function and will move more slowly,
but will provide greater torque.
Uses of gear motor
Gear motors
are commonly used in conveyor-belt drives, home appliances, in handicap and
platform lifts, medical and laboratory equipment, machine tools, packaging
machinery and printing presses. A special type of gear motor, the servo motor,
provides more power in a compact, precise fashion, and is used when a motor
with a rapid, accurate response is needed.
Figure
5: DC gear motor
