INTERNATIONALMechanical Engineering and Technology (IJMET), ISSN 0976 – International Journal of JOURNAL OF MECHANICAL ENG...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) V...
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An investigation of structural integrity of chassis mounted platform subjected

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An investigation of structural integrity of chassis mounted platform subjected

  1. 1. INTERNATIONALMechanical Engineering and Technology (IJMET), ISSN 0976 – International Journal of JOURNAL OF MECHANICAL ENGINEERING 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME AND TECHNOLOGY (IJMET)ISSN 0976 – 6340 (Print)ISSN 0976 – 6359 (Online)Volume 4, Issue 1, January- February (2013), pp. 115-122 IJMET© IAEME: www.iaeme.com/ijmet.aspJournal Impact Factor (2012): 3.8071 (Calculated by GISI)www.jifactor.com ©IAEME AN INVESTIGATION OF STRUCTURAL INTEGRITY OF CHASSIS MOUNTED PLATFORM SUBJECTED TO CONCENTRATED LOAD DURING BRAKING Prof.Dr. Matani A.G1 Prof.Deulgaonkar V.R2 Prof.Dr. Kallurkar S.P3 1 (Mechanical Engineering, Govt. College of Engineering, Amravati, Sant Gadge Baba Amravati university, Amravati, India, ashokgm333@rediffmail.com) 2 (Mechanical Engineering, Govt. College of Engineering, Amravati, Sant Gadge Baba Amravati university, Amravati, India, vikasdeulgaonkar@gmail.com) 3 (Mechanical Engineering, D.Y Patil College of Engineering, University of Pune, Pune , India, drkallurkar@yahoo.co.in ) ABSTRACT The present work deals with the investigation of strength of a specialized chassis mounted platform/structure designed to carry concentrated load. This work deals with the mathematics behind braking through shear and bending diagrams analysis processes. The perceptible loading case in the present analysis comprises braking load and its effect on the platform/structure by usage of simple shear force & bending moment diagrams. These diagrams reveal the distribution of shearing force during braking for typical Indian truck. Present analysis accentuates on the design stage aspects of the platform as this research is a step in doctoral study. Effect of load during braking for an atypical type of combination of longitudinal and cross members in platform/frame design is formulated. This paper provides a new technique for computation of strength using shear and bending diagrams. Peculiarity of this analysis is the usage of combined section modulus of three members for computation of stress. Keywords: Braking condition, horizontal load, shear stress, Structural strength shear force and bending moment diagram. 115
  2. 2. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME1. INTRODUCTION The safe and reliable use of a road vehicle necessitates the continual adjustment of itsspeed and distance in response to change in traffic conditions. Braking system in everyvehicle plays a vital role in fulfilling this requirement. Design of the braking system whichmakes an efficient use as possible of the finite amount of traction available between the tireand the road over the entire operational range is of prime importance. A detailed torquecharacteristics study of small disk brake using magnetic fluid is carried out by Hyung S.Bet.al. The torque characteristic of small disk brake by a magnetic body force is studiedthrough the relation between magnetic field intensity and rotational disk velocity [2].Dynamic stability of vehicle is evaluated using real time dynamic stability control system, adifferent approach to estimate the vehicle velocity by Li L et.al, [3]. Chul-Goo Kanganalyzed design parameters of the braking system in the development of new high speedtrain. He proposed a hardware-in-loop system for the braking system of a Korean high-speedtrain [4]. Gyu Ha Kim et.al used a virtual proving ground approach for obtaining the dynamicstress or strain distribution. Realistic boundary conditions of tire/road surface interactions areimplemented by using the virtual proving ground approach [5].2. BRAKING MECHANISM MATHEMATICS Braking performance equation is obtained from Newton’s Second Law applied inhorizontal direction. Applying the Newton’s Law to a light truck loaded with a container, weget an equation as that relates all the forces exerted during braking. The vehicle weight W issubjected to a linear deceleration, which is balanced by the total action of front & rear axlebraking force Fxf & Fxr, aerodynamic drag Da, and the sine component of weight allconsidered in horizontal direction. ୛ െ Dx ൌ െFxf െ Fxr െ Da െ Wsinθ ------ (1) ୥ -ve sign is to account for linear deceleration.For present case linear deceleration is presumed considering the adhesion between tire andground. The braking efficiency or the maximum retarding force F, applied by the brakes atthe wheels relies on the friction coefficient between the tire and the road surface and thecomponent of weight of the vehicle on the wheel. These terms are interrelated as : F ൌ µW------ (2) This shows that the braking efficiency is highly affected by the coefficient of friction.Considering all the on road possibilities, braking efficiency of 50% is hypothesized. Thecomponent of vehicle weight including the laden weight in the container generates a momentaround the centre of gravity of the vehicle. The total weight in present research is so arrangedthat it is distributed at six locations on the platform. All these locations are referred to as ISOcorner locations. Total weight of twelve tones is distributed variably at front, middle and rearISO coroners. At two front and two rear ISO corners a total load of six tone is applied 1.5tone at each. A load of six tone is applied at the two mid ISO corners, three tone each on eachside. By considering a braking efficiency of 50%, a horizontal force in addition to vertical 116
  3. 3. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEMEone acts at each ISO corner. The magnitude of each load is half the load that acts at each ISOcorner. This horizontal force is shear force that induces a shear stress at each ISO cornerlocation. The magnitude of this stress is estimated using shear force and bending momentdiagrams. The section properties of the individual members i.e. vehicle chassis, mainlongitudinal member and square cross member is evaluated in [18]. The combined sectionmodulus values of the unsymmetrical section are calculated for estimating the stress duringbraking condition.3. ESTIMATION OF SHEAR FORCE, BENDING MOMENT AND STRENGTH OF THE STRUCTURE During braking a horizontal load acts on the platform. This load acts in addition to theload in stationary condition. So, for this case the resultant bending moment is combination ofhorizontal and vertical bending moment. The support reaction calculations are done as below. ΣFy = RA + RD = 140 KN ΣMa = Ra x 0 + 35 x 0.7 + 70 x 3.55 – RD x 5.6 + 35 x 7.4 RD = 95 KN (upward) RA = 140 – RD = 45 KN (upward)During braking a horizontal force of magnitude equal to half of vertical loads magnitude atrespective ISO corner. This is taken into account by considering a moment around thecentroidal axis of outer longitudinal member.A sample calculation of shear force and bending moments in transverse direction to outerlongitudinal member is shown in table 1.The calculations for shear force and bendingmoment are tabulated below TABLE 1: Shear force and Bending Moment Sample calculations Point Shear force calculation (S.F) Bending Moment calculation (B.M) S.F Just LHS S.F Just RHS B.M Just LHS B.M Just RHS (KN) (KN) (KN-m) (KN-m) A 0 45 0 0 B 45 10 31.5 31.5 C 10 -60 60 60 D -60 35 -63 -63 E 35 0 0 0 The shear force and bending moment diagrams for both concentrated load andconcentrated load with moment around each load point is shown in fig1 and fig.2 117
  4. 4. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME Fig.1: Shear Force and Bending Moment Diagram for Concentrated Load 118
  5. 5. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME Fig.2. Shear force and Bending moment diagram for braking condition 119
  6. 6. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME3.1 Stress in the longitudinal member The resultant bending moment is the vector sum of the maximum bending moments atthe mid ISO corner. So the resultant bending moment is given as ‫ ܯ‬ൌ ඥሺ53.6ሻ2 ൅ ሺ60ሻ2 M = 80.45470776 KN-m.Using this value of bending moment we further compute stress using the fundamental ெbending equation as : ݂ ൌ ௓ --- (3). Inputting the values of maximum bending moment andsection modulus computed in (3), we get the stress magnitude at braking. 80.45470776 fሺbrakingሻ ൌ 965241.9618 fሺbrakingሻ ൌ 83.351MPaalso as the section being unsymmetrical, the stress induced during braking is evaluated fromboth sides. 80.45470776 fሺbrakingሻ ൌ 641454.3918 fሺbrakingሻ ൌ 125.425 MPa4. CONCLUSION For the design process of specialized platforms/structures mounted on chassis of truckor heavy vehicles intended for carrying containers a new method is attempted with theextension of classical method of stress computation. Estimation of load & stress inaccordance with the static and braking load is done with the aid of classical shear force andbending moment method for dynamic condition of the vehicle. The stress computed by thistechnique is well within permissible limits of yield strength of the material. Furthermore thismethod can be extended for estimation of shear stress at the load location during braking.This method provides a prior approximation of stress and stress distribution in at this variableloading condition. This method is not accurate as it gives values of stress and strain only atload location and not at the other locations on the platform. This technique also limits itsapplication in x and z directions for evaluation of stress and strain values in these directionscannot be computed.REFERENCES[1] Bum Suk Kim, Maksym Spiryagin, Bong Soo Kim, Hong Hee Yoo, Analysis of theeffects of main design parameters variation on the vibration characteristics of vehicle subframe, Journal of Mechanical Science and Technology 23(2009) 960-963.[2] Hyung-Sub Bae and Myeong-Kwan Park, A Study of Torque characteristics of smalldisk brake using magnetic fluid, Journal of Mechanical Science and Technology 25(2)(2011)349-355. 120
  7. 7. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME[3] L. Li, J. Song, L. Kong, Q. Huang, Vehicle velocity estimation for real-time dynamicstability control, International Journal of Automotive Technology 2009 Vol.10 No.6 675-685.[4] Chul-Goo Kang, Analysis of Braking System of the Korean High-Speed train usingreal time simulations, Journal of mechanical science and technology 21 (2007) 1048-1057.[5] Gyu Ha Kim, Kyu Zong Cho, In Bum Chyun, Gi Seob Choi, Dynamic stress analysisof vehicle frame using a non linear finite element method, KSME International Journal(2003) Vol.17 No.10, 1450-1457.[6] Lee, H.C., Reliability indexed sensor fusion and its application to vehicle velocityestimation, (2006) ASME, 128, 236-243.[7] Choi,S.J., Rark,J.W., and Jeon, K.K., Extreme driving characteristics estimation forESP equipped passenger car, International Journal of Automotive Technology 7,7 (2006)816-819.[8] Kato, I.,Terumichi, Y., Adachi, M. and Sogabe,K., Dynamics of track/wheel systemson high speed vehicles, Journal of Mechanical Science and technology (2005) Vol. 19, No. 1,328-335.[9] Schiehlen,W., Recent developments in multi-body dynamics, Journal of Mechanicalscience and technology (2005) Vol.19 No.1 227-236.[10] Dugoff,H., Francher, P.S. and Segal,L., An analysis of tire traction properties andtheir influence on vehicle dynamic performance (1970) SAE Paper No. 700377[11] Ilki Moon., Kyongsu Yi., Vehicle tests of a longitudinal control law for application tostop-and-go cruise control, KSME International Journal (2002) Vol.16 No.9 1166-1174.[12] Cho, D., and Hedrick, J.K., Automotive Power train modeling for control, ASMEtransactions on dynamic system, measurements and control (1989), Vol.111.[13] Choi, S., and Devlin, P., Throttle and brake combined control for intelligent vehiclehighway systems, (1995) SAE paper No. 951897.[14] Kunsoo Huh, Kyungyoung Jhang, Jaeeung Oh, Joonyoung Kim and Jaehee Hong,Development of a simulation tool for the cornering performance analysis of 6WD/6WSvehicles, KSME International Journal (1999) Vol.13No.3 211-220.[15] Bakker, E., Pacejka, H.B and Linder, L., A new tire model with an application invehicle dynamics studies (1989) SAE 890087.[16] Dhandapani N.V., Dr. Mohan Kumar G., Dr. Debanath K.K., Static analysis of off-highway vehicle chassis support for the effect of various stress distributions, InternationalJournal of Advanced Research in Technology (2012) Vol.2 Issue 1, 1-8.[17] Seong –Wan Park, Load Limits based on Rutting in pavement foundations, KSCEJournal of Civil Engineering (2004) Vol.8 No.1 23-28.[19] Deulgaonkar V.R., Dr. Matani A.G., Dr. Kallurkar S.P., Advanced MathematicalAnalysis for chassis integrated platform designed for unconventional loading by using simpletechnique for static load, International Journal of Engineering and Innovativetechnology(2012), Volume 1 Issue 3 ISSN 2277-3754.[20] Prof.Deulgaonkar V.R., Prof. Dr. Kallurkar S.P., Prof. Dr. Matani A.G., MathematicalAnalysis of Section properties of Platform Integrated with Vehicle chassis, InternationalJournal of scientific and research publications (2012), Volume 2, Issue 1, ISSN 2250-3153[21] Crolla D.A, Automotive engineering power train, chassis system and vehicle body(Butterworth-Heinemann, 2009).[22] Timoshenko S.P., Goodier J.N., Theory of Elasticity, third edition (New Delhi, TataMc-Graw Hill Edition 2010) 121
  8. 8. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 1, January - February (2013) © IAEME[23] Dr. S. K. Doifode and Dr. A. G. Matani, “Advanced Environment Protection Techniquesby Industries: Potential For Corporate Social Responsibility Activities” International Journalof Civil Engineering & Technology (IJCIET), Volume 4, Issue 1, 2013, pp. 45 - 51,Published by IAEME.[24] Onyelowe, Ken C. and Agunwamba, J.C., “Conformal Mapping And Swartz-ChristophelTransformation Of The Critical Normal Stress Distribution Of Footing On Slope”International Journal of Civil Engineering & Technology (IJCIET), Volume 3, Issue 1, 2012,pp. 128 - 135, Published by IAEME.[25] Dr. A. G. Matani, “Curricula Challenges of Technical and Management EducationInstitutions” International Journal of Management (IJM), Volume 4, Issue 1, 2013, pp. 56 -60, Published by IAEME.[26] Dr. A. G. Matani, “Effective Energy Conservation Techniques in Industries”International Journal of Mechanical Engineering & Technology (IJMET), Volume 4, Issue 1,2013, pp. 74 - 78, Published by IAEME.[27] Manjeet Singh and Dr. Satyendra Singh, “Estimation Of Stress Intensity Factor of aCentral Cracked Plate” International Journal of Mechanical Engineering & Technology(IJMET), Volume 3, Issue 2, 2012, pp. 310 - 316, Published by IAEME 122

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