CHAPTER 2 LITERATURE REVIEW 2.1Introduction This chapter provide the overview of the researchtopic related to comparison of Programmable Logic Controller (PLC) withArduino, Sorting Machine and Conveyor System. 2.2ArduinoArduino is an open source microcontroller.
Itintroduced in 2005 and it was designed to provide an inexpensive and easy wayfor hobbyists, students and professionals to create devices that can interactwith environment using sensors and actuators. Arduino can be easily programmed,erased and reprogrammed at any instant of time. Arduino as an open sourcecomputing platform for use to construct and program electronic devices.
Byattaching with various Arduino shields it can perform receive and sendinginformation over the internet. Arduino IDE (Integrated Development Environment)is the software to develop code while Arduino hardware know as Arduinodevelopment board. Simplified integrated platform provided by the Arduino IDEto run on regular personal computer and allows users to write programs forArduino using C or C++.Figure2.1.3 A labelled diagram of an Arduino Board and an IDECo-founder of Arduino, Massimo Banzi has state whyArduino are different from other controller.
The important reasons for thisquestion is:1) Active User Community:A group of people using a similar product can hold posted message conversationsand share their experiences or solve the problems of the other users in thecommunities with their own experiences 1. “If you start charging foreverything, everything dies very quickly.” says Banzi, Arduino Cofounder.2) Growth of Arduino:Arduino was developed with intent to provide an economical and trouble-free wayfor hobbyists, students and professionals to build devices that interact withtheir situation using sensors and actuators.
This makes it perfect fornewcomers to get started quickly 1.3) Inexpensive Hardware:Since Arduino is an open source platform the software is not purchased and onlythe cost of buying the board or its parts is incurred, thus making it verycheap. The hardware designs are also available online for free from itsofficial website 1.4) Arduino Board as a Programmer:To make Arduino board function easy and also making it available everywherethese boards come with a USB cable for power requirements as well asfunctioning as a programmer 1.
5) Multi-platform Environment:The Arduino IDE is capable of running on a number of platforms includingMicrosoft, Linux and Mac OS X making the user community even larger 1. 2.2Programmable Logic ControllerProgrammable Logic Controller (PLC) is a special formof microprocessor-based controller. It builds in with a programmable memory tostore instruction to implement functions such as timing, sequencing, logic,counting arithmetic as shown in the figure 2.
2.1. Figure2.2.1 Programmable Logic Controller InIndustry PLCs can be consider as special computer.
It can be operating at anyopen area due to it was vibrations, temperature, humidity and noise prove. PLCscan operate as analog or digital controller systems. It contains a hardware andsoftware systems which used for single Input/ Output or multi Inputs/Outputsmodular systems. The basicfunctional components of PLCs are processing unit, power supply unit,input/output interface section, communications interface and the programmingdevices. The basic arrangement of PLC hardware component was shown in theFigure 2.1.
2.Figure2.1.2 shown the PLC system Hand-helddevice, desktop console and a computer is a programming devices for PLC. Hand-heldprogramming devices will normally contain enough memory to allow the unit toretain programs. Desktop consoles are likely to have a visual display unit witha fully keyboard and screen display. A personal computer are widely configuredas program development work-stations. 2.
3Comparison of Arduino and PLC ProgrammableLogic Controller (PLC) has been and still is the basic controller or componentof the industrial especially in automation world. With advancement oftechnology Arduino become very famous and handy electronic development facilitydue to it was an open source controller. It has possibilities of to be used asPLCs. 1 Based onAniruddh Mali’s journal, there are two method make an Arduino as ProgrammableLogic 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 IDEi.e. LDmicro that is the editor and compiler of ladder code; second consists ofa web page that will help to creating the code for the ‘ladder.h’ library; forsimplicity’s sake, in this guide one will consider only the DIGITAL I / O withno special features.
The second method is to use plcLIB (a library that cansuitably 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 Renekerhas state that Raspberry Pi is miniaturized Linux-based single-board PC soArduino is more like a PLC. A closed-loop control of flow generated by a pumpprototype been carry out by PLC and an Arduino to see the different of this twocontroller. A sensor measures flow and send data to the Arduino,which adjusts a control valve actuator to maintain the setpoint. This projectuse Proportional–Integral–Derivative as the control algorithm which is mostbasic industrial analog automation functions.Proportional Integral been uses by the Arduino so itdoesn’t need derivative loop to read the signal from the flow meter and adjustthe valve to reach and maintain the setpoint. Arduino has both discrete andanalog Input or Output but the selection is limited.
The analog input is 0-5Vand the analog outputs are pulse-width modulation (PWM). This let the Arduinois suitable for regulating the speed of motor or for modulating a temperaturecontrol loop. In industry most of the analog instrument and actuators are designedfor 4m-20mA current loops this mean that certain modification and design needbe taken to let the Arduino can run on 2-4mA current loop. Figure 4: This flowmeterand valve represent typical industrial equipment often used to control flow.Figure 4 shown the flowmeter and valve representtypical industrial equipment often used to control flow an Arduino prototypeshield been created to mount on top of the main board to convert the 4-20mAsignal to 1.5V.
Figure 5: The signal converter board. Figure 5 shown the signal converter boards is in themiddle of the Arduino shield stack. The purpose of this board is to convertsthe two current loop inputs and changes the PWM output to a current loop forcontrol the valve.Figure 6: Pulse Width Modulation converterPulse Width Modulation is good for controlling a motoror heating element but it must be convert to a voltage or current loop to drivemost other devices. An electrically been used to isolate the 4-20mA currentloop output by using two-channel optoisolator to allow more flexibility inconnecting with other current loop devices. This was solved by powering thecircuit from the current loop itself by using a voltage-reference integratedcircuit. As we know the output of Arduino PWM will run at 500Hz.
So a Low-passfilter shown at Figure 6 will be used to removes the 500Hz signal and itsharmonics this will resulting in a dc signal proportional to the PWM dutycycle. To provide sufficient attenuation of the 500Hz component a second-orderSallen-Key active filter was designed with a cuttoff frequency of 7Hz. Anoperational amplifier been used to convert the low-pass filter output tocurrent. The resulting isolated output requires a maximum of 10V from the4-20mA current loop for power, this will result it works well in a 24V systemand this was sufficient room to fit all the signal converting circuits on thesame shield. In this experiment the author been use standard 24Vdcpower supply to powering the flowmeter and control valve the voltage also beenstep down by a simple linear regulator to 12Vdc to power the Arduino. Theflowmeter, control valve and most of PLCs are operate at 24VDC from the powersupply but Arduino will only operate on 12Vdc this mean that Arduino need anextra regulator to operate.
The second experiment been carried out by Author toshown 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 for4-20mA current loop operation, analog with several discrete outputs and inputs.The PLC was connected to the PC with an Ethernet cable and powered up with24Vdc due to the programming access to the PLC is from an external Windows PCvia Ethernet. PLC’s input and output were configured for 4-20mA via the PLC’sprogramming software so the current loop interface is not needed. PLC offers asophisticated PID instruction so it allowing the various loop parameters to beset for manual or automatic control of the loop. A simple control loop wascreated by connecting the analog output back to the analog input, again usingthe milliammeter.
Associating the PID instruction with the scaled analog inputand output allowed the PLC to learn the PID function without handling severalgallons of water. The flow sensor was connected straightforward with 24Vdcsupply so this will provide excitation for the flow sensor current loop. Do-more Designer software been use to adjustthe proportional and integral coefficients of the PID function to achievestable flow through this system. Do-more Designer software provide self-scalingplots 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 widevariety of the common support functions often needed in an industrialapplication but with some modification Arduino also can perform the samefunction. BriefHistory of Conveyor BeltIn the 19th century primitive conveyor beenused. In 1892, Thomas robin is the first person invented conveyor for productand coal transporting. Steel conveyor been invented and started production in1901 by Sandvik.
Follow by 1905 Richard Sutcliffe invented first conveyor foruse in coal mines. Henry Ford established conveyor-belt in 1913 on assemblylines at Ford Motor companies at Highland Park, Michigan factory while at 1970,the company ‘intralox’ register the first patent for all plastic, modularbelting. 4,5.According to Henry Ford, there principle of assemblywhich are:1. Placethe tools and the men in the sequence of the operation so that each componentpart shall travel the least possible distance while in the process offinishing.2. Usework slides or some other form of carrier so that when a workman completes hisoperation, he drops the part always in the same place—which place must alwaysbe the most convenient place to his hand—and if possible have gravity carry thepart to the next workman for his operation.
3. Usesliding assembling lines by which the parts to be assembled are delivered atconvenient distances. A conveying system is an automated system of conveyingsomething from one area to another. It utilizes mechanical energy, often via asystem of belts and pulleys, thereby avoiding the necessity of human or animallabour while simultaneously achieving highly predictable, repeatable speeds andperformance levels. Conveying systems may be designed to transport solids orliquids and may move massive materials, lightweight materials, or anything inbetween. Designand Development of Automated Conveyer System for Material Transporting andHandlingBased on Abhishek Kumar & Dr. Lokendra Pal Singhpaper, there was three-part need to be considered which is System Design,System Architecture and Sensing Strategies.
1. SystemDesignThe design is important to make surethe system is operating systematically. Robot been used in this paper todifferentiate the weight and the position of different places depends on theweight of the objects. The robot was designed with the capability to picking upobject form the conveyor line. 2.
SystemArchitectureAn infrared sensor been placed to oneend of the conveyor belt to detect the present of object before it was pickedup to another end of the conveyor line by a gripper which is connected to theend of two-link arm. Proportional Integral Derivate Controller at the joinsangles been used to control the double desired arm on this project. The desired arm angles values are calculatedusing the Infrared Sensor value to figure out the desired gripper position. 3. SensingStrategiesThe location of the object location,a way to sense joint angles of the arm and a way to measure the weight ofobject to picked up are the three main parts for this sensing system. To figureout where the block is located along the width of the conveyor line, a GP2DI2Sharp IR sensor been use.Loading, moving and unloading of materials onmanufacturing process been take place by the conveyor belt.
A belt conveyorconsists 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 theinventor to make this project operate more fluently. VariousType of Sorting MachineSorting Machine been invented to solve specificproblem on production line or increase the productivity. There was many type ofsorting machine been invented to solve all condition that needed in industry. Inthis part I will review various type of sorting machine that published onjournal by some expert.MaterialSorting and Stamping Machine Materialsorting and stamping machine designed for automatic sorting and stamping ofletter 6. The time saving on inspection and reduce the effort of worker beenconsidered by the author in this paper. Both mechanical and programming partare combined to make this sorting machine working successfully.
Figure7: The layout of Material Sorting and Stamping MachineFigure 7 shown the layout of material stamping sortingand stamping machine. Conveyer belt driven by the 12V DV motor for materialtransferring. Webcam and stamping machine been attached above the conveyer beltwhile the Infrared Sensor attached at the side of it. The purpose of theInfrared Sensor is to stop the conveyor belt for a moment so that the camera cantake part to capture the image of the pin code and at the same time thestamping can be done. The camera will work with MATLAB code to perform theimage recognition process. Each Pin code is assigned a value based on thesub-divisional zone of the letter belongs. If the Pin code at the letter notmatch with the database of the MATLAB, this considered that the pin codebelongs to other regions.
The target device is programmed to read thetransmitted data and control the motors attached to it to sort the letters.TheArduino controls the rotation of the servomotor and connected to the sorter bygiving a required pulse width modulated (PWM) signal so that the servo will rotatesto the particular angle and the conveyor belt drops the letter into the boxlocated at that particular angle. Once the data is received from MATLAB, thecontrollers generate a pulse signal to rotate the motor present below therotating plate to align to the particular angle. For each value received thesorter positions to the assigned value. AutomaticSorting Machine using Conveyor BeltA sorting machine is more practical and economicalmethod of automation 7. This machine been invented to sort product on themanufacture in industry. Figure 8: The layout of the Automatic Sorting MachineThis sorting machine controlled by PLC with a conveyorsystem for material handling and transporting. Sorting object will be taken bytwo of the pushing mechanism.
The layout of this sorting machine shown atFigure 8, with this simple design this machine also can perform a very powerfulsorting operation. This Automatic Sorting machine can sort three different sizeof object with reviewed the construction details of this paper, this sortingmachine consists of a conveyor belt which is driven by an electric motor. Mildsteel frame with fabricated by angles and channels been use to mount theconveyor belt.
Two journal bearing and two drum pulleys are bolted at the twoend of the frame which is the belt runs. Intermediate shafts been fabricated toact as sub frame to reduce the speed of the electric motor. Belt pulleyassemblies being use to perform the two stage of speed reduction. Sheet metalused 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 conveyorbelt. The pushing mechanism with consists of simple piston crank are mounted onthe frame for the sorting purpose.
Lastly, the provision is made for automaticswitching off the conveyor belt 7. ObjectSorting and Stacking Automation with PLCIndustry production normally generate same type ofproduct with little variation of colour, weight, shape and size this make thesorting machine play an important part in this field 8. Prof Dhaval Tailor8 proposed this prototype to solve sort and stacking at the industryproduction area. The prototype will focus on the removal of impure objects andstacking of the boxes in the stand. This whole process is done automaticallywith the help of PLC 9.
Figure 9: The complete structure of Object Sorting andStacking Automation with PLC This sorting machine designed with two conveyor beltwhich is box belt and product belt. The sorting machine is operating as theflow chart shown above. When the boxes are put on the box belt the Infrared Sensor1 will sense the present of the boxes and giving the signal to start the box beltfor 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 thismoment the product belt will turn on and identify it as box in place. A mainsensor been used to detect the defect of the product, if any defect found theproduct will be pushed into recycle bin.
If there was no defect product theproduct belt will continue moves forward. Another Infrared sensor will mouth atthe end of the product belt to sense count the number of product falling intothe box and as predefined number reaches box moves forward and is packed. Lastlythe lift will place the box at the desired place in stand once the box reachesstacking platform.