Aparna Devi .S1,Hemamalini .P2, Veena .S3,Ms.
Swagata B Sarkar,Assistant Professor, Department of Electronics and InstrumentationEngineering, Sri Sairam Engineering College, Chennai. Abstract:Millions of tons offood are processed and packaged by individuals and machines. As such, thepossibility exists that food manufacturers and the suppliers will not catchevery object that does not belong in the product. When a person consumes a foodthat has a foreign object in it, he or she may suffer a physical or emotionalinjury. This paper describes a working prototype that non-destructivelyidentifies the presence of foreign object in food products. The infrared sensormodule consists of a source and detector which will detect the presence offoreign object and thereby sends the signal to the PIC16F877A microcontrollerwhich thereby indicates the defective edible and non-defective and edible foodproducts using LED indications.
Keywords:Food Quality, Foreign Object, Infrared Sensor Module, Non-destructive testing, PIC16F877Amicrocontroller.1. Introduction:The production of safefoods for consumption is not very easy nowadays due to the ever increasing fooddemands and is greatly prone to the contamination from the external environment.So, there are chances for presence of one or more foreign objects in food.These foreign objects may be hazardous to the consumers or even fatal; hencefood quality control is essential. In earlier days, mechanical separationmethods were used to separate foreign objects from food. However, there isstill no proper technology for food quality control.
This paper therebyintroduces a non-destructive detecting module to overcome the difficultiesbeing faced in the food quality processing using infrared principle.A review says that,when nearly eight lakhs food products were scanned, more than three thousandproducts has metallic contaminations in them either in the form of strips orwires and metal balls and hairclips of varying sizes usually in the range of millimeter1.Furthermore presence of living organisms which may be undesirable in thefood, detroit the quality of food.
Thus, to assure food quality a costeffective method is necessary.Most commonly usedtechnique for detecting foreign bodies in food is by generation of ultrasonicwaves. These waves get partially reflected on the surface of foreign body. Butthe major drawback of this technique is that it works well only in acousticmedium mainly water. Hence, this technique is largely suitable for fruits andvegetables only, due to the moisture content present on their surface 2.However, ultrasound works well for sponge and wood. But itneeds a correlation with infrared for cardboard and paper like substance 3.Moreover, environmental factors create a hindrance to ultrasonic waves bychanging its velocity adapting to the surroundings 4.
Hence, foreign objectdetection using infrared radiations proves to be more efficient and economical.2. Scheme2.1Prototype Design ParametersThe proposed system isdesigned for non-destructive foreign object detection in food products. Theprototype consists of a PIC microcontroller and an infrared sensing circuitwhich is a combination of photodiode and LED.
Following the interfacing of thesensor with the PIC microcontroller, some more additional functions can beperformed by enhancing the microcontroller operation for its effectivefunctioning in determination of the defective and non-defective food products.This prototype design can be used in the industries for quality assessment oftheir end products. 2.2Infrared Sensing CircuitAn infrared sensingcircuit consists of an infrared source and an infrared detector. The source isbasically a LED which provides the required infrared radiations. Theseradiations then reflect and fall on the detector, which is basically aphotodiode. Depending upon the amount the radiations it provides a thresholdvalue to the microcontroller circuit.
This threshold value differs for defectiveand non-defective products, which is due to the presence of foreign object inthe defective food products.Fig1.Simulationof a IR Sensor Module2.2.1Penetration Depth and Penetration PowerThe IR sensors areplaced at regular intervals on either sides of the sample to avoid missing anypart of the sample during analysis. The penetration depth of IR was found to be1 to 4mm and is suitable for foreign object detection. To achieve deeperpenetration, we use a near-infrared light ranging from 750-800nm which resultsin a higher penetration power.2.
3Interfacing PIC16F18877 to the infrared sensing circuitThe output from the IRsensor module is connected to (pin number 2) RA0 of the PIC16F877A which allowsPORTB to be configured as input with TRISB registers, and the output which willbe displayed on LED is connected to RD7, RD6, RD5 (pin number 30,29,28) (PORTD)respectively and RB0(pin number 33) and RB1(pin number 34) (PORTB) which aredefined as output pins. 2.4IdentificationThe microcontrolleroutput is displayed in the following manner. When no foreign object is detectedwithin the given food sample, the LED glows green. When there is presence of aforeign object within the sample, the LED changes color from green to red. Abuzzer is also included within this unit and the buzzer goes on when the LEDglows red.3.
Circuit DescriptionThe three pins from theinfrared sensing module are connected to the rest of the circuit. Of the twopins one is connected to the input supply of the module and the other to theGND. The third pin from the infrared module is output from the module whichacts as the control pin. This output from the module is connected via thecontrol pin as the sensor input to the PIC16F877A microcontroller.The control output fromthe infrared sensing circuit is connected to RA0 (pin number 2) of a PIC16F877Amicrocontroller and the microcontroller will regard it as digital input to readeither 1 or 0.The microcontroller can read only voltages as input (either Highor low) by configuring input pins as digital to read 1 or 0 from the sensor. Sincethe output from the module is digital we can disregard the use of ADC withinthe microcontroller by configuring ADCON0bits to 0.
ADON = 0. This output fromthe IR sensing module, will make the PIC16F877A to respond by a glowing led. Unstableresults may be obtained at the default, 1 MHZ oscillator hence themicrocontroller is tuned to 8MHZ and thus solving the problem, In PIC16F877Athe 8MHz frequency is obtained by configuring the OSCCON bit settings i.e.bysetting OSCCONbits .IRCF0 = 1.
Fig2.Simulation of the PIC Interfacing With IR ModuleThe non-defectiveproduct will be prestored as 1 in the microcontroller. So, this prestored valuewill be compared to the input obtained at the microcontroller and accordinglythe LED will glow indicating the product quality.
If the input at themicrocontroller is 1 then the green LED will glow or else the red LED will glowand also a buzzer will sound indicating the defective product.3.2Software simulationProteus is the softwareis used for circuit and PCB designing. A simple software simulation of thehardware circuit was made. It’s a very simple circuit which uses comparator andgiving indications in the form of LED.
When the potential onthe LDR was LOW then the LED was observed to be in the OFF state and onincrease in the potential then the LED turned ON. Interfacing this IR modulewith PIC microcontroller and programming the controller and the port configurationwas configured in the MPLAB IDE in Embedded C.4.Results and Conclusion The non-destructive modulefor foreign object detection taking into account ten food products was tested.The penetrating depth and power for these products were determined; accordinglythe initial threshold values were being set in the microcontroller. And thusthe defective products were being identified with LED indications due to thedifference in the potential values obtained.5.Future Work This project can beextended with a conveyor belt system operated by a stepper motor.
The beltsystem carries the food products and to this system the infrared sensingcircuitry with the microcontroller can be attached. After the detection offoreign object presence the food products can be collected separately to bediscarded.6.References1.
The Risk Analysis of Metallic Foreign Bodiesin Food Products by Joanna Trafialek, Slywia Kaczmarek, Wojciech Kolanowski 2. Existingautomated foreign body-detection systems in the food industry,De MontfortUniversity, Mechanical and manufacturing engineering, The Gateway Leicester,le1 9bh, United Kingdom3. Performance comparison of Infrared and Ultrasonic sensorsfor obstacles of different materials in vehicle/ robot navigation applicationsAdarsh S1, Mohamed Kaleemuddin S1, Dinesh Bose1, K I Ramachandran21Departmentof Electronics and Communications Engineering 2Centre for ComputationalEngineering and Networking (CEN) Amrita School of Engineering, CoimbatoreAmrita Vishwa Vidyapeetham, Amrita University, India 4.
Ultrasonic and Infrared Sensors Performance in aWireless Obstacle Detection System Baharuddin Mustapha1, Aladin Zayegh1, RezaulK. Begg21College of Engineering & Science, Victoria University, Australia.2Institute of Sport, Exercise and Active Living (ISEAL) and College of Sportand Exercise Science (SES), Victoria University, Australia.