PORTABLE & AUTOMATED RICE CLEANER SYSTEM USING IMAGE PROCESSING AND PNEUMATIC CONTROL.

Abstract

ABSTRACT Rice Cleaner System using Image Processing and Pneumatic Control Portable and Automated Rice Cleaning System is proposed to enhance rice segregation. The system is designed with a compact and portable structure, ideal for handling smaller quantities of rice. It employs mechanical sieving for initial segregation, followed by a more precise process using a Pneumatic system and Image Processing technique. The machine contains three chambers: the first two chambers perform mechanical sieving through two sieves of different sizes, effectively removing larger impurities from the rice grains. This rice is then collected in the third chamber, which consists of an image processing unit and pneumatic system. A camera captures images of the rice, and an image processing algorithm detects the coordinates of finer impurities. Controlled bursts of air by the pneumatic system are then directed at these impurities, separating them from the rice. The entire process is automated and synchronized by a microprocessor.

Specification

FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
COMPLETE SPECIFICATION
(Section 10)
Portable & Automated Rice Cleaner System using Image Processing and Pneumatic Control
Applicant(s)
(1) GANDHI Raj
Nationality: Indian
Address: Sardar Patel Institute of Technology Munshi Nagar, Bhavans Campus Andheri West, MUMBAI 400058
(2) KHUNEAbhijit
Nationality: Indian
Address: Sardar Patel Institute of Technology Munshi Nagar, Bhavans Campus Andheri West, MUMBAI 400058
(3) AROLKAR Vaishnavi
Nationality: Indian
Address: Sardar Patel Institute of Technology Munshi Nagar, Bhavans Campus Andheri West, MUMBAI 400058
(4) CHIMURKAR Priya
Nationality: Indian
Address: Sardar Patel Institute of Technology Munshi Nagar, Bhavans Campus Andheri West, MUMBAI 400058
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in which it is to be performed

Portable & Automated Rice Cleaner System using Image Processing and Pneumatic Control
1. FIELD OF THE INVENTION:
This invention relates to Electronic engineering, Mechanical engineering, Automation, Image processing. Our approach is sorting the rice for dust and size followed by image processing for detecting impurities and then cleaning it using an air gun.
2. OBJECTIVE OF INVENTION:
There are four main objectives of the invention, first being, Sorting the rice mechanically & then detecting the impurities in the sorted rice using image processing. For this, we have developed and implemented a design which imitates the actual conventional process of Sieving (for removing dust particles and sorting it according to the grain size). And then passing the sorted rice through a back-lit conveyer belt with a camera module over it for image processing. Image processing marks the impurities in the image and these coordinates are then fed to air gun for further process.
Second objective of the invention is designing and implementing a pneumatic system which will be used for generating quick & controlled bursts of air. This is achieved by using relays & pneumatic valves connected to a microprocessor.
Third objective being portability of the machine. We have designed and implemented a chassis with 3 chambers stacked vertically made from Iron. Also, we have added wheels at the lower end of the chassis for easy locomotion.
Fourth objective is Automation. The whole process of sorting to cleaning is automated using microprocessor, by synchronization of the processes.
3. BACKGROUND OF THE INVENTION:
a) Under the National Food Security Act (NFSA), food-grains are provided at subsidized rates via ration shops, also called Public Distribution Systems, to over 80 crore beneficiaries. We consume almost 100 million metric tonnes of rice every year. The quality of rice available in ration shops is not at par compared to polished rice. So, we use different methods to clean and segregate the rice. Most of the households & even small-scale, medium-scale businesses (ex. Food stalls) which consumes or utilizes this rice, use traditional method (manual sieving) for cleaning the rice.
Traditional method involves a lot of manual work for cleaning and sorting. This task is done by mostly women in households of a range of ages (usually older ages). Doing it for a long time may lead to certain health issues such as eye-strain, backache and even headache. It is also inefficient as it is prone to human error which may lead to quality issues in small-scale, medium-scale businesses. These businesses require large number of quantities to be cleaned compared to households. So, the traditional method proves inefficient as it takes a lot of time to clean it manually, which may delay the further processes and consequently decrease the sales/profits.
(b) Today, there are many machines available in the market which uses the latest technologies. But these machines prove inefficient for small scale businesses where the amount of rice to be cleaned is in Kilograms, while these machines clean tonnes of rice in just few hours. Also, these are very expensive, heavy and immovable (big in size).

(c) The polished rice available in the market is expensive compared to the rice at ration shops. Due to this gap, small-scale, medium-scale businesses tend to use the ration rice for their products instead as this increases the profit margin.
4. BRIEF DESCRIPTION OF THE DRAWINGS:
Figure 1 provides flowchart of the system
Figure 2 provides Image processing results
Figure 3 provides details about parts of sieving mechanism
Figure 4 provides details about parts of image processing & pneumatic system
5. DETAILED DESCRIPTION OF THE DRAWINGS:
Figure 1: System Flowchart - Describes the process of the whole system
Figure 2: Image processing results - Shows the before and after result of image processing algorithm developed
Figure 3: Parts of Sieving mechanism
301: Larger sized Sieve - used to remove large sized impurities
302: Smaller sized Sieve - used to remove smaller sized impurities
303: Rectangular plate - for collecting rice coming from smaller sized sieve
304: Passage connecting second and bottom-most chamber - for passing the rice to bottom-most
chamber
305: Bottom-most chamber - Used for cleaning using image processing and pneumatic system
306: Second Chamber - used for smaller sized sieve mechanism
307: Top-most Chamber - used for larger sized sieve mechanism
Figure 4: Parts of Bottom-most chamber
401: Ultrasonic Distance sensor - for measuring the distance till conveyor belt
402: Camera - for capturing images of rice on the conveyor belt
403: Air gun - for shooting bursts of air
404: Robotic arm - for aiming the air gun
405: White back-lit conveyor belt - for moving the rice ahead for processing
406: Removable container for clean rice - for collecting clean rice
407: Removable container for impurities - to collect impurities shot by air gun
408: Air tank - for storing compressed air
409: Air-Compressor

6. DESCRIPTION OF THE INVENTION:
The system comprises of five major components: an iron machine structure, an electronic sieve mechanism, an image processing unit for detecting finer impurities, a pneumatic system designed to remove detected finer impurities and lastly, an Algorithm to automate and synchronize the whole process.
First, the portable machine structure consists of a cuboidal iron chassis which accommodates all the components of the machine - Sieves, camera, white back-lit conveyor belt, pneumatic system (compressor, air gun, relays, power supplies, pneumatic valves), ultrasonic distance sensor & microprocessor. It has wheels under it, which makes it easier to move. It consists of 3 hollow cuboidal chambers stacked vertically on top of each other. Top most chamber contains a larger size sieve, the second chamber contains a smaller size sieve with a rectangular plate below it, and the bottom most chamber contains a white back-lit conveyor belt, removable containers for rice (below conveyor belt) and impurities (alongside conveyor belt), camera, robotic arm and the pneumatic system. The second and the bottom-most chamber is connected by a common passage for the rice to be passed on the conveyor belt collected on the rectangular plate in the second chamber. [Figure
3]
Second, an electronic sieve mechanism. The topmost chamber & the second chamber of the machine chassis is designed such that it has rails made over the larger length edges (of the chamber's base) for the wheels and a mold for the DC motor (with a long shaft). The bases of these chambers are tilted at an elevation. Two light rectangular frameworks (made from Fiber) for the sieve, are designed such that a small rectangular strip and wheels can be attached to them & are of the same dimensions of chamber's base. Wheels are connected to both the larger length edges (of the framework).
Two rectangular iron strips are made with holes on both the ends. Both the strips are attached to the frameworks such that, one end of the strip is fixed at the middle of a smaller length edge (of a framework) such that it can rotate about this axis and the other end of the strip is left for the shaft of the DC motor. The sieves are attached to the frameworks and frameworks are then mounted in the chamber with fixing the wheels on the rails of the chamber. Now, the shaft of the DC motor is fixed to the strip such that, when the shaft starts moving, the strip reciprocates the circular motion of the shaft and the framework starts moving to and fro. The to and fro motion creates vibration which resembles the traditional method of sieving. Rails on the edges helps avoiding the frameworks being dislocated due to vibration. Additionally, the second chamber contains a solid rectangular plate (elevated at the same angle) situated right below the sieve, for the rice to be collected at the conveyor belt in the bottom-most chamber through the passage.
Sieving mechanism starts in the topmost chamber. The sieve starts vibrating when the rice is put in for the processing. Rice grains start moving down through the holes of the larger vibrating sieve to the smaller sieve. The large sized impurities remain in the sieve and move to the end of the sieve due to elevation & vibration. Impurities are collected at the end of the sieve. In the second chamber, the sieving of the rice grains starts simultaneously. Rice grains fall through this sieve on the rectangular plate and move down to the bottom-most chamber. Impurities are collected to the end of the sieve similarly like the top chamber. This chamber has smaller sized sieve and acts as a double check for the impurities to be segregated. Both the sieves, also remove the dust particles due to the vibrational motion.
Third, the Image processing Algorithm. The bottom-most chamber is completely covered from all the sides for the chamber to be dark, to avoid ambient lighting condition. The chamber consists of 4 parts, i.e., a white back-lit conveyor belt, a camera, a robotic arm and an ultrasonic distance sensor.

The rice grains segregated using the electronic sieve mechanism are passed onto the white back-lit conveyor belt, for performing image processing by the camera. The conveyor belt moves in patches of particular length (i.e. it stops for capturing the images and cleaning of a particular length of the belt). The camera is placed above the conveyor belt which captures images of the rice grains for that particular length (in RGB format) and sends them to the microprocessor. The algorithm works on the principle that light passes through the rice grains and it doesn't pass through the impurities. An ultrasonic sensor is also placed beside the camera for calculating the distance between the sensor and the conveyor belt. The value of distance between sensor and the conveyor belt is fed to the microprocessor (max_dist).
In the algorithm, gray scaling of the image happens first followed by thresholding. The value of thresholding is determined by the lighting conditions in the chamber. Thresholding detects the impurities in black color. After thresholding, contouring is applied. Contours are drawn around the black spots and the center of the contour (taking top-left pixel as the origin from where, 'x' increases to the right and *y' increases to the bottom) is calculated. Pixel to Real world unit (cm) is calculated beforehand and the value is fed to the microprocessor. The Algorithm then calculates the distance between the center of contour and Origin in the Real-world unit and returns it for further processing. [Figure 2]
In case there are no impurities detected (i.e. number of contours is '0'), there are 2 implications: (1) Rice is all clean. (2) The conveyor belt is empty (All the rice is finished cleaning). Therefore, the distance must be checked in order to understand the scenario. Distance is measured by the sensor. If, the distance measured by the sensor is less than 'max_dist', means that there is rice present on the conveyor belt and it is clean already. The conveyor belt is moved for the next patch. Else, if the distance measured is equal to 'max_dist', means that there is no rice present on the conveyor belt and the machine is stopped.
Fourth, a Pneumatic system. The system consists of a cylindrical compressed air tank (2 liters), compressor, pneumatic solenoid valves, Single Pole Single Throw (SPST) relay modules, digital pressure gauge, nozzle, power supplies (for compressor and valves). One end of the compressed air tank is connected to the compressor through a pneumatic solenoid valve in between. Similarly, the other end of the air tank is connected to the air gun. A digital Pressure gauge is installed in the air tank for measuring the pressure in the tank and sending this value to the microprocessor for decision making. Air gun is made up of a pneumatic valve whose inlet is connected to the tank and a pointed nozzle attached to the outlet of the valve.
The air compressor, pneumatic valves (including air gun) are connected to relay modules (to control the activation of valves/compressor) in such a way that - negative terminals of the power supply and the valves/compressor are connected together; positive terminal of the power supply is connected to the Common (COM) terminal; positive terminal of the valves/compressor are connected to Normally Open (NO) terminal of the relay. The relays are then connected to the microprocessor. Now, when the relay is activated by the processor, the compressor/valve gets activated due to completion of the connection. Two threshold pressure values (Upper & Lower) are set in the microprocessor for the compressor to be turned ON or OFF accordingly. Upper value is calculated by considering volume of the tank and Lower is measured by trial and error.
All the valves are closed initially. The working of the Pneumatic system starts with the measurement of the air pressure in the tank by the gauge. The measured value is then sent to the microprocessor. If the measured pressure is greater than the Lower threshold pressure value, the process of cleaning the grains through air gun starts. Else, the process of increasing the air pressure in the tank starts.

The first step of increasing air pressure involves activation of the relays of valve (connected to the compressor) first and then the compressor. The valve gets opened and the compressor is started, filling the air tank. Also, a continuous feed of air pressure values of the tank is sent from the gauge to the microprocessor. The compressor is kept ON until the pressure value meets the Upper threshold value. Once the pressure is equal to or greater than the Upper threshold value, the compressor is turned OFF by deactivating its relay. The valve is also closed similarly. Now, the air tank is ready to use for cleaning the rice grains.
Air gun is attached to a robotic arm which is mounted to one side of conveyor belt. It will fire controlled bursts of air in the direction towards the container for impurities (located alongside conveyor belt opposite to the air gun). The cleaning of finer impurities starts with the robotic arm aiming the gun towards the impurities one by one according to the given coordinates (from image processing). Air gun is activated through the activation of the relay connected to its pneumatic valve. For controlled bursts of air, the relay is activated for a very short amount of time. The pressurized air passes through a pointed nozzle attached to the air gun which in turn helps to clean smaller sized impurities from the rice grains. The impurities are deposited in the container for impurities. Activation of the air gun relay is counted in the microprocessor. The pressure of the tank is checked after every burst and the compressor is started if the pressure gets low than Lower threshold value (by stopping the current process of cleaning by air gun). This process repeats until all the rice is cleaned. After the count matches the number of count of impurities, conveyor belt moves ahead for the next patch (as the conveyor belt is at halt since the image processing is started), the cleaned rice gets deposited in the container of rice and cleaning of next patch starts. Also, after cleaning process of rice is done, the container of impurities can be removed and cleaned. [Figure 4]
Fifth, an algorithm for synchronizing & automating all the processes. All the process from electronic sieving of the rice to the detection of impurities and cleaning of the rice by image processing and pneumatic system is automated by the algorithm taking into account all the timely requirements. [Figure 1]

7. SUMMARY OF INVENTION
• The invention comprises a rice segregation and cleaner machine featuring an integrated system of vibratory sieves and air blowers.
• The vibratory sieves are designed to remove large size debris and dust, while the air blowers remove finer impurities.
• This dual-action mechanism improves the quality of cleaned rice and increases processing speed.
• The machine is equipped with adjustable settings, allowing operators to customize the cleaning process for different rice varieties.
• It will replicate the rice mills and processing plants system, significantly improving operational efficiency for those small-scale business and directly improving product quality & can also be used at homes.

CLAIMS Portable & Automated Rice Cleaner System using Image Processing and Pneumatic Control
We Claim,
1.
(a) A portable machine structure
(b) An electronic sieve mechanism
(c) An image processing algorithm for rice grain
(d) A pneumatic system for further cleaning the impurities in rice
(e) An algorithm for synchronizing & automating all the processes

2. A portable machine structure mentioned in claim 1(a), where in, it accommodates all the machine components and is movable.
3. An electronic sieve mechanism mentioned in claim 1(b), where sorting of different sizes of rice and removal of dust particles takes place.
4. An image processing algorithm for rice mentioned in claim 1(c), by which finer impurities in the rice are detected using thresholding and contouring.
5. A pneumatic system for further cleaning the impurities in rice mentioned in claim 1(c), through which detected impurities are then removed through controlled bursts of air which are produced by the pneumatic system.
6. An algorithm for synchronizing & automating all the processes mentioned in claim 1, by which the whole process of cleaning of rice is automated (using microprocessor).

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