- Email: [email protected]
Finite Element Analysis for Stress Distribution of Hand Tool Harvester
Available online at www.sciencedirect.com
ScienceDirect Procedia Engineering 68 (2013) 219 – 224
Malaysian International Tribology Conference 2013, (MITC2013)
Finite Element Analysis for Stress Distribution of Hand Tool Harvester M.A.H.A. Ssomada, R.M. Hudzaria*, M.N.A. Noordinb, S.M. Sapuanc, N. Norhayatia, A.J. Soranb b
a Faculty of Agriculture and Biotechnology, Universiti Sultan Zainal Abidin (UniSZA), 20400 KualaTerengganu, Terengganu, Malaysia. Faculty of Innovative Design and Technology, Universiti Sultan Zainal Abidin (UniSZA), 20400 KualaTerengganu, Terengganu, Malaysia. c Faculty of Engineering, Universiti Putra Malaysia (UPM),43400, Serdang,Selangor, Malaysia
Abstract This paper introduced the essential development of an innovative hand tool harvester since harvesting the tuber of Dioscorea hispida is tedious and difficult while the existing hand tool is heavy. The information of optimum force required from field experiment is used to model the simulation and practicability in Computer Aided Design (CAD) environment system. Several tests of maximum/minimum stress and displacement on different material of hand tool were simulated by uploading the material characteristic on simulation program embedded in Solidworks software. Three materials which were commonly available in market namely Plain Carbon Steel, Aluminium Alloy and Cast Carbon Steel were chosen. This modeling software is very helpful to manage the model and simulate the workability of the designed equipment through stress and displacement mode analysis. The comparison between the tools that are based on the acquired land and tuber weight factor were also noted via Solidworks simulation. The end result of the simulation is based on visualization of analysis in Solidworks while producing the hand tool for designing and fabrication from lighter and stronger material.
© TheAuthors. Authors.Published Published Elsevier © 2013 2013 The byby Elsevier Ltd.Ltd. Selection and under responsibility of The Tribology Society (MYTRIBOS), Department of Mechanical The Malaysian Tribology Society (MYTRIBOS), Department Selection andpeer-review peer-review under responsibility of Malaysian Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia of Mechanical Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia. Keywords: Innovative hand tool harvester; finite element; stress distribution; solidworks simulation; measurement monitoring ____________________________________________________________________________________________________________________
1. Introduction Dioscorea hispida is one of the Discorea spp (Yam) species and characterize as a climbing plants with glamorous leaves and twining stems, which helix readily around the stem. Dioscorea hispida is commonly found in secondary forest and grow under shaded areas or near streams which is known by the local or vernacular names such as Ubi Gadong [1]. Dioscorea hispida which entitle Ubi Gadong in Malaysia one of the most economically important agriculture in yam species, which serves as a fast food for a millions of people in tropical and subtropical countries [2 - 4]. Figure 1 shows the tuber of Dioscorea hispida. This plant is classified as a wild creeping and climbing plant which can grow up to 20 meters in height [2]. * Corresponding author. Tel.+6 09 668 8527; fax: +609 666 0244. E-mail address: [email protected]
1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of The Malaysian Tribology Society (MYTRIBOS), Department of Mechanical Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia doi:10.1016/j.proeng.2013.12.171
220
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224
Fig. 1. The tubers and stem for Dioscorea hispida during field harvesting.
2. Methodology Reverse engineering concept was applied where it initially involved extraction of the design layout of the machine, development of schematic drawing and wireframe model, design modification in computer aided design (CAD) environment, design simulation and finally is the complete drawing for fabrication purposes [4,5]. Conceptual designs of the tools were developed and these designs are important in product development [6-8]. Therefore, a new tool fixture equipped with digital force gauge device to gripped it stem is required. The finite element method (FEM) is a numerical technique for finding approximate solutions to partial differential equations (PDE) and their systems, as well as integral equations. In simple terms, FEM is a method for dividing up a very complicated problem into small elements that can be solved in relation to each other. Its practical application often known as finite element analysis (FEA) [10]. The main features of FEA method are the entire solution domain is divided into small finite segments (hence the name finite element) and over each element the behaviour is described by the displacement of the elements and the material law. All elements are assembled together and the requirement of continuity and equilibrium are satisfied between neighbouring elements while provided that the boundary conditions of the actual problem a satisfied a unique solution can be obtained to the overall system of hour algebra equation [11]. Stress is generally defined as the average for (F) per unit area (A).The solution matrix is sparsely populated. 3. Result and Discussion Table 1 shows the mechanical properties of selected materials that were tested for finite element analysis. First are Aluminum Alloy (201.0-T7 Insulated Mold Casting), second Cast Carbon Steel and third Plain Carbon Steel. All mechanical properties are uploaded from database of solidwork simulation express. It’s were purposely to determine the highest strength of selected material for hand tool. From table 1 the lightest material is Aluminum Alloy (201.0T7 casting mold Insulated ss) with value of 3.14054kg while the volume is 0.00112162m3. The heaviest material is Cast Carbon Steel (SN) with value of 12.0077 kg with volume of 0.00153945 m3. Table 1. Material, mass, volume and density of design for innovative hand tool
Material 1.Aluminium Alloy (Insulated Mold Casting ) 2.Cast Carbon Steel 3.Plain Carbon Steel
Mass 3.14054 kg 12.0077 kg 8.74864 kg
Volume
Density 3
0.00112162 m
3
0.00112162 m 0.00112162 m3
2800 Kg/m3 10706 Kg/m3 7800 Kg/m3
3.1 Simulation Result on Mechanical Properties Hand tool is designed and modeled in solidworks modeling software. Four materials are used to simulate its mechanical properties as shown in Table 2. Figure 2, 3 and 4 are shown the stress distribution on designed hand tool for material of Aluminum Alloy, Cast Carbon Steel and Plain Carbon Steel respectively.
221
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224 Table 2. The material properties of hand tool harvester material
Property Name Elastic modulus Poisson's ratio Shear modulus Mass density Tensile strength Yield strength Thermal expansion coefficient Thermal conductivity Specific heat Hardening factor (0.01.0; 0.0=isotropic; 1.0=kinematic)
Aluminium Alloy Insulated Mold Casting
Plain Carbon Steel
Cast Carbon Steel
210000000000 0.28 79000000000 7800 399830000 220590000
200000000000 0.32 76000000000 7800 482550000 248170000
71000000000 0.33 23000000000 2800 345000000 344000000
0.000013
0.000012
0.000019
/Kelvin
43 440
30 500
121 963
W/(m.K) J/(kg.K)
NA
NA
0.85
NA
Units N/m^2 NA N/m^2 kg/m^3 N/m^2 N/m^2
Fig. 2 show the Aluminium Alloy (201.0-T7 Insulated Mold Casting (a) stress (max & Min) and (b) Factor of Safety (F.O.S), Fig. 3 show the Cast carbon steel (a)stress (max & Min) (b) Factor of Safety (F.O.S) and Fig. 4 show the Plain Carbon Steel (a) stress (max & Min) (b) Factor of Safety (F.O.S).Factor of Safety (F.O.S) of 5 is used in all simulation process of material. It purposely just to show that with this F.O.S, the critical stress point affected on hand tool is removed and meant that it was conceptually safe to use in real application. As shown in Fig. 2 (a), the stress point for material Aluminium Alloy (201.0-T7 Insulated Mold Casting), showing critical value of 210105520.0 N/m2. Fig. 2 (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed.
(2a)
(2b)
Fig. 2. Alluminium Alloy (201.0-T7 Insulated Mold Casting) (a) Stress (max at below & min at top) (b) Factor of safety (F.O.S).
As shown in Fig 3. (a), the stress point for material Cast carbon steel, showing critical value of 210105520.0 N/m2.Fig 3. (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed.
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(3a)
(3b) Fig. 3. Cast carbon steel (a) Stress (b) Factor of safety (F.O.S).
As shown in Fig. 4. (a), the stress point for material Plain Carbon Steel, showing critical value of 210537168.0 N/m2. Fig. 4 (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed. As in conclusion, the lowest stress point on bend type harvester shows that Aluminum Alloy (Insulated Mold Casting) is suitable to be used for fabrication of this hand tool. The Factor of Safety (F.O.S) with value of 5 shows that critical value of stress is removed in all type of material.
(4a)
(4b)
Fig. 4. Plain carbon steel (a) Stress (b) Factor of safety (F.O.S).
223
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224
The easiness and practicability to develop a hand tool is the priority to overcome the application of manual harvesting for the farmer at the remote areas.The ergonomic and strangeness criteria of hand tool design and material are selected for benchmarking of research analysis. From the result, the Alluminium Alloy is selected due to lightness in weight of material while the stress force distribution effected during harvesting process is lowest as shown in Fig 2. The simulation result in CAD modeling software was visually compared with actual field test. The stress point was not affected during field test since the straight hand tool made of mild steel and cast iron are strong enough for pulling up the Dioscorea hispida tuber. The actual force required for harvesting process varies and need to be measured intensively since the type of soil and the age of tubers will effect on its difficultness. It was found that the force requirement for harvesting Dioscorea hispida tuber has a direct relation with its weight. [10,11]. The displacement factor that make of the bend type design of hand tool having results of the user/farmer less require to push the tool to a flat position on the surface of the ground and this was what actually happened during the field test. To reduce the displacement part, is where the idea comes for a bend hand tool harvester. The design of a bend type was further analyzed using Solidworks software in which the simulation program is very useful in the designing stage before deriving at the correct fabrication and efficiency of the final product [10]. At this experiments three type of hand tools designs are analysed, there are; bend, fulcrum and straight design. The easiness and practicability to develop a hand tool is the priority to overcome the application of manual harvesting for the farmer at the remote areas. To determine the efficiency on predicting the force requirement for harvesting the Dioscorea hispida tuber, the Regression analysis tool package form Microsoft Excel is used and the output summary is shown in Table 3. Levine mentioned that all three criteria below must be followed to determine the regression efficiency of the multiple regression must be above than 0.8 while the significance statistic must be lower than 0.05 and the t-statistic must be is larger than 1.96 and 1.64 for alpha 0.05 and 0.10 respectively [12]. Table 3. Statistical summary output for relationship of force harvesting with weight of Dioscorea hispida
Regression Statistics Multiple R R Square Adjusted R Square Standard Error Observations ANOVA(analysis of variance)
0.86 0.74 0.73 183.71 19.00
Df Regression Residual Total
Intercept X Variable 1
SS
1.00 17.00 18.00
1641545.45 573769.29 2215314.74
Coefficients
Standard Error
-230.59 721.77
113.52 103.49
MS
F
1641545.45 33751.13
48.64
t Stat
P-value
-2.03 6.97
0.06 0.00
Significance F 2.24E06
Lower 95% -470.09 503.42
Upper 95% 8.90 940.12
From table 3, the multiple Regression value is 0.86 while the significance statistics (significance F) is lower than 0.05 which indicate 2.24E-06. The absolute value of t-statistic (t-stat) is 6.97 which are larger than 1.96 and 1.64 for alpha 0.05 and 0.10 respectively. This proved that using second polynomial regression equation, the maximum force that used for simulation in finite analysis is acceptable and accuracy. The Dioscorea hispida tubers are harvested from three different area whereas at Kampung Kudat, Kampung Bukit Diman and Ladang UniSZA Gong Badak Terengganu, Malaysia. The soil type for this experiment area is sandy clay loam which represents 30% clay, 10% silt and 60% sand while from the regression formula, which expressed relationship between force for harvesting and
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weight of tuber in sandy clay loam area, is; Y=615.17x2 - 468.24x + 241.28 with R2= 0.86 where; Y is force for harvesting Dioscorea hispida tuber (in Newton), X is weight of Dioscorea hispida tuber (in kilogram) and R2 is regression squared. 5.0 Conclusions An innovative hand tool harvester is important to replace the traditional method of harvesting the tuber of Dioscorea hispida in remote areas. The mobility and weight issues are raised for replacing such traditional method during harvesting the tuber of Dioscorea hispida from remote areas. The solid modeling software is useful for designing, modeling and simulating the workability of the designed equipment in CAD environment system. The finite element simulation program embedded in solid modeling software is helpful for designing and modeling stage. The simulation analysis will enable the designer to choose the strongest material and model for the fabrication stage. The concept of easy handling and user friendly are the priority areas addressed in Dioscorea hispida research conducted at UniSZA. The application of technology in area of composite material and automation could be further explored in designing this hand tool harvester. Finally the product could be made commercially available. Acknowledgements The authors are thankful to Unit Perancangan Ekonomi Negeri (UPEN), Terengganu, Malaysia for sponsoring the agriculture mechanization research for Dioscorea Hispida. The authors with to thank Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia and Universiti Putra Malaysia for their supports. Greatest thank to the Al Mighty ALLAH who provided health and strength to do this research. References [1] Nashriyah M, Nornasuha Y, Salmah T, Norhayati N and Mohd.Rohaizad .2010.Dioscorea Hispida Dennst. (Dioscoreaceae): An Overview. Buletin UniSZA, No. 4, ISSN 2180-0235 [2] Hahn, S.K. 1995. Yams:Dioscorea spp. (Dioscorea). In: J. Smartt and N.W. Simmonds (Eds), Evolution of crop plants,. Longman Scientific and technical, UK, pp:112-120. [3] Udensi E.A., Oselebe H.O., and Iweala O.O .2008.”The Investigation of Chemical Composition and Functional Properties of Water Yam (Dioscorea alata): Effect of Varietal Differences”. Pakistan Journal of Nutrition, 7(2):pp. 324-344. [4] Mohd.Hudzari Hj Razali, Hasbullah Hj Muhammad, Noordin Asimi Mohd and Wan Ishak Wan Ismail .2011.”A Review on Farm Mechanization and Analysis Aspect for Dioscorea Hispida”. Journal of Crop Science, 2(1): pp. 21-26. [5] Darius El Pebrian and Azmi Yahya. 2003.”Design and Development of a Prototype Trailed Type Oil palm Seedling Transplanter.” Journal Oil Palm Research, 15(1):pp.32-40. [6] Sarah, K.B .2008.The Architectural designer and Their Digital Media. PhD Thesis, Royal Melbourne Institute of Technology (RMIT) University. [7] Sapuan S.M., M.R. Osman and Y. Nukman.2006.”State of the-art of the concurrent engineering technique in automotive industry”. Journal of Engineering Design. 17(2):pp.143 - 157. [8] Sapuan S.M., M.A. Maleque, M. Hameedullah, M.N. Suddin and N. Ismail.2005.”A note on the conceptual design of polymeric composite automotive bumper system”, Journal of Materials Processing Technology. 159(2):pp.145 - 151. [9] Sapuan S.M., S.S.S. Imihezri, S. Sulaiman, M. Hamdan and E.S. Zainudin.2007. “Comparison of simulated and actual product of polymer composite automotive clutch pedal”. International Journal of Mechanical and Materials Engineering, 2(1): pp. 29 – 39. [10] Hudzari R.M., S.M. Sapuan, N.A Noordin, M.Hasbullah, M.A.H.A Ssomad and R.Syazili (2012), “Simulation and Practicability Analysis Of Innovative Hand Tool Harvester”, Scientific, Research and Essays. 7(19): pp. 1864-1871. [11] M.A.H.A Ssomad, R.M. Hudzari, M.N.A Noordin, S.J. Abdullah, S.M Sapuan and S.Hassan (2013) Simulation and Analysis of Force Requirement for harvesting Dioscorea hispida tubers, Advance Research Material Vol. 626: pp. 459-463. [12] Levine D.M., Ramsey P.P and R.K. Smidt (2001), Applied Statistics for Engineers and Scientist Using Microsoft Excel, Prentice Hall.
ScienceDirect Procedia Engineering 68 (2013) 219 – 224
Malaysian International Tribology Conference 2013, (MITC2013)
Finite Element Analysis for Stress Distribution of Hand Tool Harvester M.A.H.A. Ssomada, R.M. Hudzaria*, M.N.A. Noordinb, S.M. Sapuanc, N. Norhayatia, A.J. Soranb b
a Faculty of Agriculture and Biotechnology, Universiti Sultan Zainal Abidin (UniSZA), 20400 KualaTerengganu, Terengganu, Malaysia. Faculty of Innovative Design and Technology, Universiti Sultan Zainal Abidin (UniSZA), 20400 KualaTerengganu, Terengganu, Malaysia. c Faculty of Engineering, Universiti Putra Malaysia (UPM),43400, Serdang,Selangor, Malaysia
Abstract This paper introduced the essential development of an innovative hand tool harvester since harvesting the tuber of Dioscorea hispida is tedious and difficult while the existing hand tool is heavy. The information of optimum force required from field experiment is used to model the simulation and practicability in Computer Aided Design (CAD) environment system. Several tests of maximum/minimum stress and displacement on different material of hand tool were simulated by uploading the material characteristic on simulation program embedded in Solidworks software. Three materials which were commonly available in market namely Plain Carbon Steel, Aluminium Alloy and Cast Carbon Steel were chosen. This modeling software is very helpful to manage the model and simulate the workability of the designed equipment through stress and displacement mode analysis. The comparison between the tools that are based on the acquired land and tuber weight factor were also noted via Solidworks simulation. The end result of the simulation is based on visualization of analysis in Solidworks while producing the hand tool for designing and fabrication from lighter and stronger material.
© TheAuthors. Authors.Published Published Elsevier © 2013 2013 The byby Elsevier Ltd.Ltd. Selection and under responsibility of The Tribology Society (MYTRIBOS), Department of Mechanical The Malaysian Tribology Society (MYTRIBOS), Department Selection andpeer-review peer-review under responsibility of Malaysian Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia of Mechanical Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia. Keywords: Innovative hand tool harvester; finite element; stress distribution; solidworks simulation; measurement monitoring ____________________________________________________________________________________________________________________
1. Introduction Dioscorea hispida is one of the Discorea spp (Yam) species and characterize as a climbing plants with glamorous leaves and twining stems, which helix readily around the stem. Dioscorea hispida is commonly found in secondary forest and grow under shaded areas or near streams which is known by the local or vernacular names such as Ubi Gadong [1]. Dioscorea hispida which entitle Ubi Gadong in Malaysia one of the most economically important agriculture in yam species, which serves as a fast food for a millions of people in tropical and subtropical countries [2 - 4]. Figure 1 shows the tuber of Dioscorea hispida. This plant is classified as a wild creeping and climbing plant which can grow up to 20 meters in height [2]. * Corresponding author. Tel.+6 09 668 8527; fax: +609 666 0244. E-mail address: [email protected]
1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of The Malaysian Tribology Society (MYTRIBOS), Department of Mechanical Engineering, Universiti Malaya, 50603 Kuala Lumpur, Malaysia doi:10.1016/j.proeng.2013.12.171
220
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224
Fig. 1. The tubers and stem for Dioscorea hispida during field harvesting.
2. Methodology Reverse engineering concept was applied where it initially involved extraction of the design layout of the machine, development of schematic drawing and wireframe model, design modification in computer aided design (CAD) environment, design simulation and finally is the complete drawing for fabrication purposes [4,5]. Conceptual designs of the tools were developed and these designs are important in product development [6-8]. Therefore, a new tool fixture equipped with digital force gauge device to gripped it stem is required. The finite element method (FEM) is a numerical technique for finding approximate solutions to partial differential equations (PDE) and their systems, as well as integral equations. In simple terms, FEM is a method for dividing up a very complicated problem into small elements that can be solved in relation to each other. Its practical application often known as finite element analysis (FEA) [10]. The main features of FEA method are the entire solution domain is divided into small finite segments (hence the name finite element) and over each element the behaviour is described by the displacement of the elements and the material law. All elements are assembled together and the requirement of continuity and equilibrium are satisfied between neighbouring elements while provided that the boundary conditions of the actual problem a satisfied a unique solution can be obtained to the overall system of hour algebra equation [11]. Stress is generally defined as the average for (F) per unit area (A).The solution matrix is sparsely populated. 3. Result and Discussion Table 1 shows the mechanical properties of selected materials that were tested for finite element analysis. First are Aluminum Alloy (201.0-T7 Insulated Mold Casting), second Cast Carbon Steel and third Plain Carbon Steel. All mechanical properties are uploaded from database of solidwork simulation express. It’s were purposely to determine the highest strength of selected material for hand tool. From table 1 the lightest material is Aluminum Alloy (201.0T7 casting mold Insulated ss) with value of 3.14054kg while the volume is 0.00112162m3. The heaviest material is Cast Carbon Steel (SN) with value of 12.0077 kg with volume of 0.00153945 m3. Table 1. Material, mass, volume and density of design for innovative hand tool
Material 1.Aluminium Alloy (Insulated Mold Casting ) 2.Cast Carbon Steel 3.Plain Carbon Steel
Mass 3.14054 kg 12.0077 kg 8.74864 kg
Volume
Density 3
0.00112162 m
3
0.00112162 m 0.00112162 m3
2800 Kg/m3 10706 Kg/m3 7800 Kg/m3
3.1 Simulation Result on Mechanical Properties Hand tool is designed and modeled in solidworks modeling software. Four materials are used to simulate its mechanical properties as shown in Table 2. Figure 2, 3 and 4 are shown the stress distribution on designed hand tool for material of Aluminum Alloy, Cast Carbon Steel and Plain Carbon Steel respectively.
221
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224 Table 2. The material properties of hand tool harvester material
Property Name Elastic modulus Poisson's ratio Shear modulus Mass density Tensile strength Yield strength Thermal expansion coefficient Thermal conductivity Specific heat Hardening factor (0.01.0; 0.0=isotropic; 1.0=kinematic)
Aluminium Alloy Insulated Mold Casting
Plain Carbon Steel
Cast Carbon Steel
210000000000 0.28 79000000000 7800 399830000 220590000
200000000000 0.32 76000000000 7800 482550000 248170000
71000000000 0.33 23000000000 2800 345000000 344000000
0.000013
0.000012
0.000019
/Kelvin
43 440
30 500
121 963
W/(m.K) J/(kg.K)
NA
NA
0.85
NA
Units N/m^2 NA N/m^2 kg/m^3 N/m^2 N/m^2
Fig. 2 show the Aluminium Alloy (201.0-T7 Insulated Mold Casting (a) stress (max & Min) and (b) Factor of Safety (F.O.S), Fig. 3 show the Cast carbon steel (a)stress (max & Min) (b) Factor of Safety (F.O.S) and Fig. 4 show the Plain Carbon Steel (a) stress (max & Min) (b) Factor of Safety (F.O.S).Factor of Safety (F.O.S) of 5 is used in all simulation process of material. It purposely just to show that with this F.O.S, the critical stress point affected on hand tool is removed and meant that it was conceptually safe to use in real application. As shown in Fig. 2 (a), the stress point for material Aluminium Alloy (201.0-T7 Insulated Mold Casting), showing critical value of 210105520.0 N/m2. Fig. 2 (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed.
(2a)
(2b)
Fig. 2. Alluminium Alloy (201.0-T7 Insulated Mold Casting) (a) Stress (max at below & min at top) (b) Factor of safety (F.O.S).
As shown in Fig 3. (a), the stress point for material Cast carbon steel, showing critical value of 210105520.0 N/m2.Fig 3. (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed.
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(3a)
(3b) Fig. 3. Cast carbon steel (a) Stress (b) Factor of safety (F.O.S).
As shown in Fig. 4. (a), the stress point for material Plain Carbon Steel, showing critical value of 210537168.0 N/m2. Fig. 4 (b) show the Factor of Safety (F.O.S) of 5, the critical point of stress is removed. As in conclusion, the lowest stress point on bend type harvester shows that Aluminum Alloy (Insulated Mold Casting) is suitable to be used for fabrication of this hand tool. The Factor of Safety (F.O.S) with value of 5 shows that critical value of stress is removed in all type of material.
(4a)
(4b)
Fig. 4. Plain carbon steel (a) Stress (b) Factor of safety (F.O.S).
223
M.A.H.A. Ssomad et al. / Procedia Engineering 68 (2013) 219 – 224
The easiness and practicability to develop a hand tool is the priority to overcome the application of manual harvesting for the farmer at the remote areas.The ergonomic and strangeness criteria of hand tool design and material are selected for benchmarking of research analysis. From the result, the Alluminium Alloy is selected due to lightness in weight of material while the stress force distribution effected during harvesting process is lowest as shown in Fig 2. The simulation result in CAD modeling software was visually compared with actual field test. The stress point was not affected during field test since the straight hand tool made of mild steel and cast iron are strong enough for pulling up the Dioscorea hispida tuber. The actual force required for harvesting process varies and need to be measured intensively since the type of soil and the age of tubers will effect on its difficultness. It was found that the force requirement for harvesting Dioscorea hispida tuber has a direct relation with its weight. [10,11]. The displacement factor that make of the bend type design of hand tool having results of the user/farmer less require to push the tool to a flat position on the surface of the ground and this was what actually happened during the field test. To reduce the displacement part, is where the idea comes for a bend hand tool harvester. The design of a bend type was further analyzed using Solidworks software in which the simulation program is very useful in the designing stage before deriving at the correct fabrication and efficiency of the final product [10]. At this experiments three type of hand tools designs are analysed, there are; bend, fulcrum and straight design. The easiness and practicability to develop a hand tool is the priority to overcome the application of manual harvesting for the farmer at the remote areas. To determine the efficiency on predicting the force requirement for harvesting the Dioscorea hispida tuber, the Regression analysis tool package form Microsoft Excel is used and the output summary is shown in Table 3. Levine mentioned that all three criteria below must be followed to determine the regression efficiency of the multiple regression must be above than 0.8 while the significance statistic must be lower than 0.05 and the t-statistic must be is larger than 1.96 and 1.64 for alpha 0.05 and 0.10 respectively [12]. Table 3. Statistical summary output for relationship of force harvesting with weight of Dioscorea hispida
Regression Statistics Multiple R R Square Adjusted R Square Standard Error Observations ANOVA(analysis of variance)
0.86 0.74 0.73 183.71 19.00
Df Regression Residual Total
Intercept X Variable 1
SS
1.00 17.00 18.00
1641545.45 573769.29 2215314.74
Coefficients
Standard Error
-230.59 721.77
113.52 103.49
MS
F
1641545.45 33751.13
48.64
t Stat
P-value
-2.03 6.97
0.06 0.00
Significance F 2.24E06
Lower 95% -470.09 503.42
Upper 95% 8.90 940.12
From table 3, the multiple Regression value is 0.86 while the significance statistics (significance F) is lower than 0.05 which indicate 2.24E-06. The absolute value of t-statistic (t-stat) is 6.97 which are larger than 1.96 and 1.64 for alpha 0.05 and 0.10 respectively. This proved that using second polynomial regression equation, the maximum force that used for simulation in finite analysis is acceptable and accuracy. The Dioscorea hispida tubers are harvested from three different area whereas at Kampung Kudat, Kampung Bukit Diman and Ladang UniSZA Gong Badak Terengganu, Malaysia. The soil type for this experiment area is sandy clay loam which represents 30% clay, 10% silt and 60% sand while from the regression formula, which expressed relationship between force for harvesting and
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weight of tuber in sandy clay loam area, is; Y=615.17x2 - 468.24x + 241.28 with R2= 0.86 where; Y is force for harvesting Dioscorea hispida tuber (in Newton), X is weight of Dioscorea hispida tuber (in kilogram) and R2 is regression squared. 5.0 Conclusions An innovative hand tool harvester is important to replace the traditional method of harvesting the tuber of Dioscorea hispida in remote areas. The mobility and weight issues are raised for replacing such traditional method during harvesting the tuber of Dioscorea hispida from remote areas. The solid modeling software is useful for designing, modeling and simulating the workability of the designed equipment in CAD environment system. The finite element simulation program embedded in solid modeling software is helpful for designing and modeling stage. The simulation analysis will enable the designer to choose the strongest material and model for the fabrication stage. The concept of easy handling and user friendly are the priority areas addressed in Dioscorea hispida research conducted at UniSZA. The application of technology in area of composite material and automation could be further explored in designing this hand tool harvester. Finally the product could be made commercially available. Acknowledgements The authors are thankful to Unit Perancangan Ekonomi Negeri (UPEN), Terengganu, Malaysia for sponsoring the agriculture mechanization research for Dioscorea Hispida. The authors with to thank Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia and Universiti Putra Malaysia for their supports. Greatest thank to the Al Mighty ALLAH who provided health and strength to do this research. References [1] Nashriyah M, Nornasuha Y, Salmah T, Norhayati N and Mohd.Rohaizad .2010.Dioscorea Hispida Dennst. (Dioscoreaceae): An Overview. Buletin UniSZA, No. 4, ISSN 2180-0235 [2] Hahn, S.K. 1995. Yams:Dioscorea spp. (Dioscorea). In: J. Smartt and N.W. Simmonds (Eds), Evolution of crop plants,. Longman Scientific and technical, UK, pp:112-120. [3] Udensi E.A., Oselebe H.O., and Iweala O.O .2008.”The Investigation of Chemical Composition and Functional Properties of Water Yam (Dioscorea alata): Effect of Varietal Differences”. Pakistan Journal of Nutrition, 7(2):pp. 324-344. [4] Mohd.Hudzari Hj Razali, Hasbullah Hj Muhammad, Noordin Asimi Mohd and Wan Ishak Wan Ismail .2011.”A Review on Farm Mechanization and Analysis Aspect for Dioscorea Hispida”. Journal of Crop Science, 2(1): pp. 21-26. [5] Darius El Pebrian and Azmi Yahya. 2003.”Design and Development of a Prototype Trailed Type Oil palm Seedling Transplanter.” Journal Oil Palm Research, 15(1):pp.32-40. [6] Sarah, K.B .2008.The Architectural designer and Their Digital Media. PhD Thesis, Royal Melbourne Institute of Technology (RMIT) University. [7] Sapuan S.M., M.R. Osman and Y. Nukman.2006.”State of the-art of the concurrent engineering technique in automotive industry”. Journal of Engineering Design. 17(2):pp.143 - 157. [8] Sapuan S.M., M.A. Maleque, M. Hameedullah, M.N. Suddin and N. Ismail.2005.”A note on the conceptual design of polymeric composite automotive bumper system”, Journal of Materials Processing Technology. 159(2):pp.145 - 151. [9] Sapuan S.M., S.S.S. Imihezri, S. Sulaiman, M. Hamdan and E.S. Zainudin.2007. “Comparison of simulated and actual product of polymer composite automotive clutch pedal”. International Journal of Mechanical and Materials Engineering, 2(1): pp. 29 – 39. [10] Hudzari R.M., S.M. Sapuan, N.A Noordin, M.Hasbullah, M.A.H.A Ssomad and R.Syazili (2012), “Simulation and Practicability Analysis Of Innovative Hand Tool Harvester”, Scientific, Research and Essays. 7(19): pp. 1864-1871. [11] M.A.H.A Ssomad, R.M. Hudzari, M.N.A Noordin, S.J. Abdullah, S.M Sapuan and S.Hassan (2013) Simulation and Analysis of Force Requirement for harvesting Dioscorea hispida tubers, Advance Research Material Vol. 626: pp. 459-463. [12] Levine D.M., Ramsey P.P and R.K. Smidt (2001), Applied Statistics for Engineers and Scientist Using Microsoft Excel, Prentice Hall.