This chapter provide the overview of the research
topic related to comparison of Programmable Logic Controller (PLC) with
Arduino, Sorting Machine and Conveyor System.
Arduino is an open source microcontroller. It
introduced in 2005 and it was designed to provide an inexpensive and easy way
for hobbyists, students and professionals to create devices that can interact
with environment using sensors and actuators. Arduino can be easily programmed,
erased and reprogrammed at any instant of time. Arduino as an open source
computing platform for use to construct and program electronic devices. By
attaching with various Arduino shields it can perform receive and sending
information over the internet. Arduino IDE (Integrated Development Environment)
is the software to develop code while Arduino hardware know as Arduino
development board. Simplified integrated platform provided by the Arduino IDE
to run on regular personal computer and allows users to write programs for
Arduino using C or C++.
2.1.3 A labelled diagram of an Arduino Board and an IDE
Co-founder of Arduino, Massimo Banzi has state why
Arduino are different from other controller. The important reasons for this
1) Active User Community:
A group of people using a similar product can hold posted message conversations
and share their experiences or solve the problems of the other users in the
communities with their own experiences 1.
“If you start charging for
everything, everything dies very quickly.” says Banzi, Arduino Cofounder.
2) Growth of Arduino:
Arduino was developed with intent to provide an economical and trouble-free way
for hobbyists, students and professionals to build devices that interact with
their situation using sensors and actuators. This makes it perfect for
newcomers to get started quickly 1.
3) Inexpensive Hardware:
Since Arduino is an open source platform the software is not purchased and only
the cost of buying the board or its parts is incurred, thus making it very
cheap. The hardware designs are also available online for free from its
official website 1.
4) Arduino Board as a Programmer:
To make Arduino board function easy and also making it available everywhere
these boards come with a USB cable for power requirements as well as
functioning as a programmer 1.
5) Multi-platform Environment:
The Arduino IDE is capable of running on a number of platforms including
Microsoft, Linux and Mac OS X making the user community even larger 1.
Programmable Logic Controller
Programmable Logic Controller (PLC) is a special form
of microprocessor-based controller. It builds in with a programmable memory to
store instruction to implement functions such as timing, sequencing, logic,
counting arithmetic as shown in the figure 2.2.1.
2.2.1 Programmable Logic Controller
Industry PLCs can be consider as special computer. It can be operating at any
open area due to it was vibrations, temperature, humidity and noise prove. PLCs
can operate as analog or digital controller systems. It contains a hardware and
software systems which used for single Input/ Output or multi Inputs/Outputs
functional components of PLCs are processing unit, power supply unit,
input/output interface section, communications interface and the programming
devices. The basic arrangement of PLC hardware component was shown in the
2.1.2 shown the PLC system
device, desktop console and a computer is a programming devices for PLC. Hand-held
programming devices will normally contain enough memory to allow the unit to
retain programs. Desktop consoles are likely to have a visual display unit with
a fully keyboard and screen display. A personal computer are widely configured
as program development work-stations.
Comparison of Arduino and PLC
Logic Controller (PLC) has been and still is the basic controller or component
of the industrial especially in automation world. With advancement of
technology Arduino become very famous and handy electronic development facility
due to it was an open source controller. It has possibilities of to be used as
Aniruddh Mali’s journal, there are two method make an Arduino as Programmable
Logic Controller. First one is to write a program using KOP language (ladder).
To do that, one should use two more applications in addition to Arduino IDE
i.e. LDmicro that is the editor and compiler of ladder code; second consists of
a web page that will help to creating the code for the ‘ladder.h’ library; for
simplicity’s sake, in this guide one will consider only the DIGITAL I / O with
no special features. The second method is to use plcLIB (a library that can
suitably modified to take advantage of the IO shield coupled with Arduino UNO)
so that user can edit the project code with a language similar to AWL
(instructions: IF, AND, OR) having the control on timers and other functions.
Arduino vs PLC for industrial control 2 by Doug Reneker
has state that Raspberry Pi is miniaturized Linux-based single-board PC so
Arduino is more like a PLC. A closed-loop control of flow generated by a pump
prototype been carry out by PLC and an Arduino to see the different of this two
A sensor measures flow and send data to the Arduino,
which adjusts a control valve actuator to maintain the setpoint. This project
use Proportional–Integral–Derivative as the control algorithm which is most
basic industrial analog automation functions.
Proportional Integral been uses by the Arduino so it
doesn’t need derivative loop to read the signal from the flow meter and adjust
the valve to reach and maintain the setpoint. Arduino has both discrete and
analog Input or Output but the selection is limited. The analog input is 0-5V
and the analog outputs are pulse-width modulation (PWM). This let the Arduino
is suitable for regulating the speed of motor or for modulating a temperature
control loop. In industry most of the analog instrument and actuators are designed
for 4m-20mA current loops this mean that certain modification and design need
be taken to let the Arduino can run on 2-4mA current loop.
Figure 4: This flowmeter
and valve represent typical industrial equipment often used to control flow.
Figure 4 shown the flowmeter and valve represent
typical industrial equipment often used to control flow an Arduino prototype
shield been created to mount on top of the main board to convert the 4-20mA
signal to 1.5V.
Figure 5: The signal converter board.
Figure 5 shown the signal converter boards is in the
middle of the Arduino shield stack. The purpose of this board is to converts
the two current loop inputs and changes the PWM output to a current loop for
control the valve.
Figure 6: Pulse Width Modulation converter
Pulse Width Modulation is good for controlling a motor
or heating element but it must be convert to a voltage or current loop to drive
most other devices. An electrically been used to isolate the 4-20mA current
loop output by using two-channel optoisolator to allow more flexibility in
connecting with other current loop devices. This was solved by powering the
circuit from the current loop itself by using a voltage-reference integrated
circuit. As we know the output of Arduino PWM will run at 500Hz. So a Low-pass
filter shown at Figure 6 will be used to removes the 500Hz signal and its
harmonics this will resulting in a dc signal proportional to the PWM duty
cycle. To provide sufficient attenuation of the 500Hz component a second-order
Sallen-Key active filter was designed with a cuttoff frequency of 7Hz. An
operational amplifier been used to convert the low-pass filter output to
current. The resulting isolated output requires a maximum of 10V from the
4-20mA current loop for power, this will result it works well in a 24V system
and this was sufficient room to fit all the signal converting circuits on the
In this experiment the author been use standard 24Vdc
power supply to powering the flowmeter and control valve the voltage also been
step down by a simple linear regulator to 12Vdc to power the Arduino. The
flowmeter, control valve and most of PLCs are operate at 24VDC from the power
supply but Arduino will only operate on 12Vdc this mean that Arduino need an
extra regulator to operate.
The second experiment been carried out by Author to
shown the different of Arduino and PLC. In this demonstration a low-end PLC.
The PLC has one analog input and one analog output, both of it configurable for
4-20mA current loop operation, analog with several discrete outputs and inputs.
The PLC was connected to the PC with an Ethernet cable and powered up with
24Vdc due to the programming access to the PLC is from an external Windows PC
via Ethernet. PLC’s input and output were configured for 4-20mA via the PLC’s
programming software so the current loop interface is not needed. PLC offers a
sophisticated PID instruction so it allowing the various loop parameters to be
set for manual or automatic control of the loop. A simple control loop was
created by connecting the analog output back to the analog input, again using
the milliammeter. Associating the PID instruction with the scaled analog input
and output allowed the PLC to learn the PID function without handling several
gallons of water. The flow sensor was connected straightforward with 24Vdc
supply so this will provide excitation for the flow sensor current loop. Do-more Designer software been use to adjust
the proportional and integral coefficients of the PID function to achieve
stable flow through this system. Do-more Designer software provide self-scaling
plots of both the process variable and the control variables, allowing clear,
real-time monitoring of system performance.
This both prototype shown that PLC offers a wide
variety of the common support functions often needed in an industrial
application but with some modification Arduino also can perform the same
History of Conveyor Belt
In the 19th century primitive conveyor been
used. In 1892, Thomas robin is the first person invented conveyor for product
and coal transporting. Steel conveyor been invented and started production in
1901 by Sandvik. Follow by 1905 Richard Sutcliffe invented first conveyor for
use in coal mines. Henry Ford established conveyor-belt in 1913 on assembly
lines at Ford Motor companies at Highland Park, Michigan factory while at 1970,
the company ‘intralox’ register the first patent for all plastic, modular
According to Henry Ford, there principle of assembly
the tools and the men in the sequence of the operation so that each component
part shall travel the least possible distance while in the process of
work slides or some other form of carrier so that when a workman completes his
operation, he drops the part always in the same place—which place must always
be the most convenient place to his hand—and if possible have gravity carry the
part to the next workman for his operation.
sliding assembling lines by which the parts to be assembled are delivered at
convenient distances. A conveying system is an automated system of conveying
something from one area to another. It utilizes mechanical energy, often via a
system of belts and pulleys, thereby avoiding the necessity of human or animal
labour while simultaneously achieving highly predictable, repeatable speeds and
performance levels. Conveying systems may be designed to transport solids or
liquids and may move massive materials, lightweight materials, or anything in
and Development of Automated Conveyer System for Material Transporting and
Based on Abhishek Kumar & Dr. Lokendra Pal Singh
paper, there was three-part need to be considered which is System Design,
System Architecture and Sensing Strategies.
The design is important to make sure
the system is operating systematically. Robot been used in this paper to
differentiate the weight and the position of different places depends on the
weight of the objects. The robot was designed with the capability to picking up
object form the conveyor line.
An infrared sensor been placed to one
end of the conveyor belt to detect the present of object before it was picked
up to another end of the conveyor line by a gripper which is connected to the
end of two-link arm. Proportional Integral Derivate Controller at the joins
angles been used to control the double desired arm on this project. The desired arm angles values are calculated
using the Infrared Sensor value to figure out the desired gripper position.
The location of the object location,
a way to sense joint angles of the arm and a way to measure the weight of
object to picked up are the three main parts for this sensing system. To figure
out where the block is located along the width of the conveyor line, a GP2DI2
Sharp IR sensor been use.
Loading, moving and unloading of materials on
manufacturing process been take place by the conveyor belt. A belt conveyor
consists of an endless and flexible belt of high strength with two end pulleys
(driver and driven) at fixed positions supported ‘by rollers is used by the
inventor to make this project operate more fluently.
Type of Sorting Machine
Sorting Machine been invented to solve specific
problem on production line or increase the productivity. There was many type of
sorting machine been invented to solve all condition that needed in industry. In
this part I will review various type of sorting machine that published on
journal by some expert.
Sorting and Stamping Machine
sorting and stamping machine designed for automatic sorting and stamping of
letter 6. The time saving on inspection and reduce the effort of worker been
considered by the author in this paper. Both mechanical and programming part
are combined to make this sorting machine working successfully.
7: The layout of Material Sorting and Stamping Machine
Figure 7 shown the layout of material stamping sorting
and stamping machine. Conveyer belt driven by the 12V DV motor for material
transferring. Webcam and stamping machine been attached above the conveyer belt
while the Infrared Sensor attached at the side of it. The purpose of the
Infrared Sensor is to stop the conveyor belt for a moment so that the camera can
take part to capture the image of the pin code and at the same time the
stamping can be done. The camera will work with MATLAB code to perform the
image recognition process. Each Pin code is assigned a value based on the
sub-divisional zone of the letter belongs. If the Pin code at the letter not
match with the database of the MATLAB, this considered that the pin code
belongs to other regions. The target device is programmed to read the
transmitted data and control the motors attached to it to sort the letters.
Arduino controls the rotation of the servomotor and connected to the sorter by
giving a required pulse width modulated (PWM) signal so that the servo will rotates
to the particular angle and the conveyor belt drops the letter into the box
located at that particular angle. Once the data is received from MATLAB, the
controllers generate a pulse signal to rotate the motor present below the
rotating plate to align to the particular angle. For each value received the
sorter positions to the assigned value.
Sorting Machine using Conveyor Belt
A sorting machine is more practical and economical
method of automation 7. This machine been invented to sort product on the
manufacture in industry.
Figure 8: The layout of the Automatic Sorting Machine
This sorting machine controlled by PLC with a conveyor
system for material handling and transporting. Sorting object will be taken by
two of the pushing mechanism. The layout of this sorting machine shown at
Figure 8, with this simple design this machine also can perform a very powerful
sorting operation. This Automatic Sorting machine can sort three different size
of object with reviewed the construction details of this paper, this sorting
machine consists of a conveyor belt which is driven by an electric motor. Mild
steel frame with fabricated by angles and channels been use to mount the
conveyor belt. Two journal bearing and two drum pulleys are bolted at the two
end of the frame which is the belt runs. Intermediate shafts been fabricated to
act as sub frame to reduce the speed of the electric motor. Belt pulley
assemblies being use to perform the two stage of speed reduction. Sheet metal
used to avoid idling, it acts as a scrubber and to reduce the dust on the belt.
Sensor to detect the present of object been mounted on the side of the conveyor
belt. The pushing mechanism with consists of simple piston crank are mounted on
the frame for the sorting purpose. Lastly, the provision is made for automatic
switching off the conveyor belt 7.
Sorting and Stacking Automation with PLC
Industry production normally generate same type of
product with little variation of colour, weight, shape and size this make the
sorting machine play an important part in this field 8. Prof Dhaval Tailor
8 proposed this prototype to solve sort and stacking at the industry
production area. The prototype will focus on the removal of impure objects and
stacking of the boxes in the stand. This whole process is done automatically
with the help of PLC 9.
Figure 9: The complete structure of Object Sorting and
Stacking Automation with PLC
This sorting machine designed with two conveyor belt
which is box belt and product belt. The sorting machine is operating as the
flow chart shown above. When the boxes are put on the box belt the Infrared Sensor
1 will sense the present of the boxes and giving the signal to start the box belt
for the transporting purpose. Once the boxes reached the second Infrared Sensor,
this sensor will be giving another signal to PLC to stop the box belt on this
moment the product belt will turn on and identify it as box in place. A main
sensor been used to detect the defect of the product, if any defect found the
product will be pushed into recycle bin. If there was no defect product the
product belt will continue moves forward. Another Infrared sensor will mouth at
the end of the product belt to sense count the number of product falling into
the box and as predefined number reaches box moves forward and is packed. Lastly
the lift will place the box at the desired place in stand once the box reaches