DESIGN, ANALYSIS AND DEVELOPMENT OF LOW COST MODIFIED PEDAL POWERED MAIZE DESHELLER

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1 Proceeding of NCRIET-2015 & Indian J.Sci.Res. 12(1): , 2015 ISSN: (Print) ISSN: (Online) DESIGN, ANALYSIS AND DEVELOPMENT OF LOW COST MODIFIED PEDAL POWERED MAIZE DESHELLER M. RAJASHEKAR a1 AND S. MOHANKUMAR b a Research Scholar, Mech. Engg. Department, SDMCET, Dharwad, VTU, Belgaum, India b Principal, SDMCET, Dharwad, VTU, Belgaum, India ABSTRACT Majority rural areas of developing countries, the maize corns are removed from the cob by hand. Existing alternatives to deshelling maize by hand are often unaffordable or difficult to obtain for subsistence farmers. Deshelling of maize is done by beating or by nibbling the cobs with fingers. Deshelling by beating causes injury to the grains whereas nibbling with hands involves long time and drudgery. Hence a Low cost Pedal powered Maize Sheller is designed and developed with easily and readily available scrap parts in day to day life. It generates power through human pedalling and with the drive mechanism, converts the pedalling motion into required rotary motion of the drum. Its innovation lies in its simple design, use of inexpensive parts, very low repairing and maintenance cost, affordability to poor farmer and it does not affect the environment. First all the components are designed and assembled using CATIA V5 software. Simulating product designs in the virtual world, where design flaws can be discovered and rectified in a timely manner before the design goes into production, can increase the quality of the design, eliminate costly recalls later, and increase the reputation of the company and product. The power from pedal was transmitted to the driving shaft bevel gear and then to bevel gear of vertical shaft which contains sprocket, chain drive of the Deshelling unit. 3D model of Maize Desheller was imported in.stp format to ANSYS software and conducted the kinematic and static stress analysis. The developed Pedal powered Maize Sheller was tested in field as well as operations at load for short durations. The analysis of data collected during the short duration test revealed that the machine is stable and strong and its speed of operation 100 rpm was quite satisfactory. The Deshelling capacity of the machine was kg/hr with Deshelling efficiency of % and cleaning efficiency of 97.64%. The breakage percentage was 0.03 which is well within the prescribed limit for such machines. The labor requirement was reduced by % using this machine. KEYWORDS: CATIA CAD model, Pedal power, Bicycle chain, Bevel gear Low cost, stress analysis, FEA, Maize Desheller In countries like South America, Central America, parts of South East Asia and India, the maize covers an area of 6.5 million hectors producing 6 million tonnes of maize per annum. An estimated 550 million small-holder farmers in the world lack access to mechanized agricultural technology. Maize can be preserved for a long period. It also finds a large application in a number ways like manufacture of alcohol, corn starch, corn syrup etc. Maize is becoming the third major crop of the country after rice and wheat. Deshelling of the maize cob are done mostly by the farm women in the country [Singh, S. P, 2006].The possibility of maize cultivation during winter increases the yield. The erratic rainfall pattern of south west monsoon affects timely field operation in the Khariff season. Lower photo respiration losses and night temperature favours maize cultivation crop efficiently in rabbi season. The Deshelling of corns from the corns are rigidly held in a symmetric manner along the length and circumference of the Cob. Now these difficulties are much reduced as different methods of Deshelling are available. Generally harvesting of maize crop is being done manually with traditional hand tool sickle. After harvesting, cobs are plucked manually by hand and cobs are dried in sunshine to reduce moisture content to 15-21%.Industrial maize Desheller are prohibitively expensive, with a cost range of Rs.75, ,000. Small-scale hand-cranked or pedalpowered maize shellers cost range of Rs.15, ,000, which is still more than many families can afford. While industrial shellers are highly productive, their energy infrastructure requirements can render them unusable in rural villages. Furthermore, mechanized equipment and stationary pedal-powered devices are difficult to transport to the users. As a consequence, farmers may be required to travel long distances to process their crops or the technology may not be able to reach the communities who need it most. Joseph S Lombardo [Joseph S Lombardo, 1996] has presented collaborative virtual prototyping as an application of advanced 1 Corresponding author

2 information technology for the design, modeling, analysis, simulation, manufacturing, testing and logistics to support the life cycle development of a product. Manjunath & Mohan Kumar have clearly discussed about Virtual Prototyping an aid to the development of a Multifunctional Robot[Mohan Kumar S, 2008]. Rajashekar & Mohan Kumar shown that how Virtual Prototype Modelling and Analysis can be used in developing Low cost Hand operated Maize Desheller [Rajashekar M, 2015] In general machinery fabrication industries, CAD technology has been very widely applied to various fields. But Farm machinery still remains an the primary stage, which based on hand work such as objects, models and drawings and samples to complete the whole process of Farm machinery body design method without using the modern CAD design software tools. At present, foreign farm machinery companies have started to use CAD modern technology, while problems such as not precise enough, long design cycle still exist in domestic agricultural machinery companies. METHODS AND MATERIALS Moisture content seriously affects the shelling ability of maize corn. An average moisture content of 14% to 18% for maize that was to be deshelled was reported by [Fashina, A.B, 1994]. Another factor that affect the thresh ability of maize in a mechanized system is the size of the maize cob. The mechanical shellers need to be adjusted to the various sizes of cobs. According to [Joshi, H.C, 1981] the various sizes of maize cob ranges from 50mm to 85mm depending on variety. This Desheller consists of base frame, seat, two deshelling blade units, power transmission unit with bevel gears, chain sprocket and outlet with two PVC elbow. The base frame was made of mild steel square hollow tube for providing support to all other machine components. The GI tube of 75mm diameter was selected based on 15 to 20% larger then maximum diameter of maize cobs. In order to deshell the cob one end of the cob as inserted into GI pipe the inner surface of the pipe was welded by deshelling blades longitudinally 3 rows which helps to detach maze corns the height of the blade was designed depend on the length of the maize corns plus 5% extra length. The maize cob were inserted one by one to both Sheller blades by one operator and other is required for pedalling., the shearing action of the blades welded inside the pipe surface, the corn were separated from the cobs and then collected through the outlet 76mm PVC elbow fitted at the bottom of the pipe frame. Both the workers could be interchanged during operation to increase the productivity and continuity in operation. The 3-dimensional solid model of the Desheller is established by using CATIA V5 software and imported into ANSYS [Rajashekar M, 2014].Then Material properties are assigned to each component motion constraints are added to the model. To simulate the model motions are added at each joint. In order to achieve the desired planning results, motion planning of each joint motor and the corresponding expression or data points of spline interpolation must be given. [Devnani, R.S]. The simulation has to be carried out for 0-30 sec. To simulate the model motion is applied at each joint. Then measure the forces at each and every joint of the rigid model of Desheller machine. Figure 1: CATIA CAD model of Maize Desheller Figure 2: Orthographic view of Pipe Desheller with sprocket

3 Figure 3: CATIA CAD model of Base frame Design Considerations We know that human has applied energy through the use of arms, hands,legs and back. A person can generate four times more power by pedaling than by hand cranking. At the rate of 200 watts, continuous pedaling can be done for only short periods, about 10 minutes. However, pedaling at half this power 100watts can be sustained for around 60 minutes. Figure 5: Imported ANSYS Model (.step format) Table 1: Physical Properties of Maiz Corn MAIZE COB SIZE,mm Fields Medium Minimum D1 D2 L D1 D2 L (1) (2) (3) Table 2: Properties of Structural Steel The uniqueness of this design is that it works on a different principle of deshelling. The earlier mentioned design by [1], worked on the principle of impact force, while this design works on the principle of abrasion; an application of force tangentially on a surface. Force required to deshell the maize is F = mω 2 r - (1) corn, Where F = force required to Deshell maize m = mass of deshelling unit, ω = angular velocity of shaft. - (2) ω =2πN/60, Where N = 100 rpm Figure 4: Orthographic view of Assembled Desheller Power Transmission Unit The chain and sprockets of ordinary bicycle was used for transmission of power. The bigger sprocket connected with two pedals acts as

4 driver and drives one smaller sprocket via chain. The power from pedal was transmitted to the driving shaft bevel gear and then to bevel gear of vertical shaft which contains sprocket, chain drive of the Deshelling unit. The peddling can be easily done by operator by sitting on seat and power gets transmitted to deshelling units. The diameter and number of teeth on driver and driven sprockets were 177.8mm and 44 and 76.2mm and 18. Figure 8: Meshed FEA model of Maize Desheller Table 4: Mesh Properties of Maiz Desheller Figure 6: a) CAD model b) Actual Maize cob Figure 7: Stress Analysis using ANSYS Workbench Table 3: Physical Properties of Maiz Desheller Figure 9: Equivalent Elastic strain Maize Desheller Figure 20: Von-misses stress Desheller unit

5 Figure 13: Normal Stress Maize Desheller Figure 42: Total Deformation at transmission shaft and handle Figure 53: Variation of Power output with pedalling rate Figure 64: Fabricated Modified Maize Desheller RESULTS AND DISCUSSION A solid geometry of Maize Desheller were developed in CATIA software and exported as (.STP) file to the ANSYS software. The next important steps are meshing and applying loading and boundary conditions in the pre-processor so that simulation can be run to get a solution and generate results in the post-processor. The minimum and maximum developed stress in the fastened area of the base frame and deshelling blade was indicated in the plots varying from colours from blue to red respectively. The colour indicated from blue to red is the minimum and maximum value for all the deflection and stresses on the blade respectively were shown in Figure It was observed that, the maximum and minimum principal stresses for base frame were found to be e8Pa and 1.872e7Pa respectively with a total deformation of 5.723e-2 mm. The stress values were within the limits of the yield stress of the material. Table 3: Performance Total Deshelling Considering Removal of Seeds Considering of Damages Total Deshelling 98% 99% 98.05% 98.1% 99.5% 98.60% 97.8% 99.2% 98.01% The Pedaling force of 200N in the Sheller represents a 48.82% increase in deshelling potential compared to that of the cob master machine. The torque of 12.36N-m compared to 18Nm at 100rpm

6 represents a 31.33% reduction in energy input also reflected by 20.59% reduction in crank Force energy input. The total cost of fabrication of the design s prototype is affordable to a group of rural farmers or even individual farmers compared to the cumulative costs of service hiring or purchase of industrial shellers. The Desheller can help to substantially reduce the human labor involved in Deshelling at an affordable cost and also reduces the time used for operation on small farms. CONCLUSIONS The analysis of kinematic behaviour of the Sheller unit with a shaft mounted on bearings with bevel gears. The use of computer method allowed reflects a real behaviour of Maize Desheller. The output of hand deshelling by men, hand tubular shelling, pedal operated three blade Deshelling and four blade technique were 10 to 15kg per hour, 20 to 24kg per hour [9], 75 to 85 kg per hour and 100 to 110kg per hour respectively. Hand Deshelling was found lowest output capacity due to tiredness and drudgery of labour among all deshellers output capacity of modified pedal powered maize Desheller was 8 to 9 times more than bare hand Deshelling and 3 to 4 times hand operated shelling. This is due to ease of operation and comfortness. The Deshelling capacity of the machine was kg/hr with Deshelling efficiency of % and cleaning efficiency of 97.64%. The breakage percentage was 0.03 which is well within the prescribed limit for such machines. The labor requirement was reduced by % using this machine. ACKNOWLEDGMENT We express our first and fore most panamas to his Holiness Ma. Gha. Cha. Channabasava Pattadevaru, Dr.Bheemanna Khandre Founder President, Er.Eshwar Khandre president SVE Society. The authors acknowledge with heart full thanks to professor, MCE, Hassan Dr.S.Mohankumar who made this Endeavour possible and also express our gratitude and indebtedness to SDMCET Dharwad Research centre and his holiness of Poojya Dr. D. Veerendra Heggade, president SDME Society for providing us an opportunity to undergo research work successfully. REFERENCES Fashina, A.B. and Abdulahi, H. (1994). Performance evaluation of a locally developed direct-power-take off driven maize thresher. Journal of Agricultural Technology, NBTE, Vol. 2(1), 1-5. Joshi, H.C. (1981). Design and selection of thresher parameters and components. Journal of Agricultural Mech. In Asia, Africa and Latin America; Vol. 12(2), J.N. Nwakairea, B.O. Ugwuishiwub, Ohagwuc, Design, Construction & Performance Analysis of A Maize Thresher for Rural Dweller Nigerian Journal of Technology Vol. 30, No. 2, pp49-54 June Devnani, R.S. Farm implements developed under 1CAR coordinated scheme during Agricultural Engineering Today, 6(4): 40. Singh S P; Singh Pratap Pedal powered Maize Dehusker-Sheller for Farm Women. Agricultural Engineering Today 34 (1): Singh, S. P., Gite, L P and Agarwal, N Improved farm tools and equipment for women workers for increased productivity and reduced drudgery. Gender, Technology and Development, 10 (2): Joseph S Lombardo, Edward Mihalak, and Scott R. Osborne, Collaborative Virtual Prototyping, Johns Hopkins APL Technical Digest, Vol. 17, No. 3, 1996, pp Mohan Kumar S. and Manjunath K., Virtual Prototyping An Approach to the Conceptual Design for a Jointed Arm Robot, National Conference under TEQIP on Emerging Trends in Mechanical Engineering (ETIME-2008) held during 28th 29th August, 2008 at B.M.S. College of Engineering, Bangalore, Karnataka, pp.58. Rajashekar M, Virtual Prototype Modelling and Analysis of Low cost Hand operated Maize Desheller Indian Journal of Scientific Research, Vol. 11, May 2015, pp

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