International Journal of Research and Innovation (IJRI)
International Journal of Research and Innovation (IJRI) 1401-1402
REDUCTION OF IMPACT EFFECT ON CAR BUMPER USING MEMORY SHAPE ALLOY PADS.
M.Arun Kumar, 1, Y Anil Reddy2, Godi Subba Rao3, 1 Research Scholar, Department of Mechanical Engineering, Hyderabad Institute of Technology and Management, Hyderabad, India 2 Assistant professor, Department of Mechanical Engineering, Hyderabad Institute of Technology and Management,Hyderabad, India 3 professor, Department of Mechanical Engineering, Hyderabad Institute of Technology and Management, Hyderabad, India
Abstract Bumper is one of the most important parts in passenger cars for which the material and structure should be considered in order to reduce the impact of collision. Since suitable impact strength is the main expectation for such a structure, the authors survey the variables that directly give impact characteristics and wished for easily achievable modifications resulting from impact modeling on commercial bumpers. Many researchers have studied that accident always occurs in front side. The impressed the authors to study and analyses the component related to frontal crash and therefore, the authors selected bumper. Aim of the project work is reduce the effort of car bumper by introducing honey comb structure instead of regular rubber block as impact block. •Initially data collection and literature survey will be done to understand the problem and rectification methodology. •A parametric model and design will be prepared using reverse engineering process. •Structural analysis will be carryout on regular and with honey comb structured damper pad with rubber and NITINOL material as a damper element. •Impact analysis will be carryout on bumper with honey comb structured damper pad. •Comparison will be done between result of traditional and honey comb structured bumper pad. •Graphs and tables will be prepared for easy understanding and comparison.
*Corresponding Author: M.Arun Kumar, Research Scholar, Department of Mechanical Engineering, Hyderabad Institute of Technology and Management, Hyderabad, India Published: July 04, 2015 Review Type: peer reviewed Volume: I, Issue : IV
Citation: M.Arun Kumar, Research Scholar (2015) REDUCTION OF IMPACT EFFECT ON CAR BUMPER USING MEMORY SHAPE ALLOY PADS.
PROBLEM DESCRIPTION AND METHODOLOGY Car bumper is used for the protection of passengers, generally steel or impact grade plastics are used as bumper material along with rubber pads between chassis and bumper. As per the previous research passenger’s protection can be increased up to 34% by increasing bumper thickness. But the percentage of passenger safety is not satisfactory even after modifications. This is an attempt to increase the passenger’s safety by implementing honey comb structure and (NITINOL) memory shape alloy which is used as damper strings. The following process will be followed to increase passenger’s safety. 1)Parametric model will be created to conduct analysis. 2)Structural analysis will be conducted on normal model to evaluate the results ( for comparison purpose). 3)Analysis will be carried out by changing bumper materials.
4)Honey comb structure pad with rubber and memory shape alloy will be analyzed to determine impact conditions. INTRODUCTION TO BUMPER OF A CAR An automobile's bumper is the front-most or rear-most part, ostensibly designed to allow the car to sustain an impact without damage to the vehicle's safety systems. They are not capable of reducing injury to vehicle occupants in high-speed impacts, but are increasingly being designed to mitigate injury to pedestrians struck by cars. First standards In 1971, the U.S. National Highway Traffic Safety Administration (NHTSA) issued the country's first regulation applicable to passenger car bumpers. Federal Motor Vehicle Safety Standard No. 215 (FMVSS 215), "Exterior Protection," took effect on 1 September 1972 — when most automakers would begin producing their model year 1973 vehicles. The standard prohibited functional damage to specified safety-related components such as headlamps and fuel system components when the vehicle is subjected to barrier crash tests at 5 miles per hour (8 km/h) for front and 2.5 miles per hour (4 km/h) for rear bumper systems. In October 1972, the U.S. Congress enacted the Motor Vehicle Information and Cost Saving Act (MVICS), which required NHTSA to issue a bumper standard that yields the "maximum feasible reduction of cost to the public and to the consumer". Factors considered included the costs and benefits of implementation, the standard's effect on insurance costs and legal fees, savings in consumer time and inconvenience, and health and safety considerations. The 1973 model year passenger cars sold in the U.S. used 130
International Journal of Research and Innovation (IJRI)
a variety designs. They ranged from non-dynamic versions with solid rubber guards, to "recoverable" designs with oil and nitrogen filled telescoping shock-absorbers. The standards were further beefed up for the 1974 model year passenger cars with standardized height front and rear bumpers that could take angle impacts at 5-mile-perhour (8 km/h) with no damage to the car's lights, safety equipment, and engine. This often meant additional overall vehicle length, as well as new front and rear designs to incorporate the stronger energy absorbing bumpers. TYPES OF BUMPERS PLASTIC BUMPER CARBON FIBRE BUMPER BOBY KIT BUMPER STEEL BUMPER PLASTIC BUMPER Most modern cars use a reinforced thermoplastic bumper, as they are cheap to manufacture, easy to fit and absorb more energy during a crash. A majority of car bumpers are custom made for a specific model, so if you are looking to replace a cracked bumper with a similar one, you would have to buy from a specialist dealer. However, many companies now offer alternative designs in thermoplastic, with a range of fittings designed for different models.
location of a feature, the physical lines on the drawing must be changed (in each affected view) then associated dimensions are updated. When using parametric modeling, the features are driven by the dimensions (parameters). To modify the diameter of a hole, the hole diameter parameter value is changed. This automatically modifies the feature wherever it occurs - drawing views, assemblies, etc. Another unique attribute of Creo2.0 (PRO/ENGINEER)is that it is a solid modeling program. The design procedure is to create a model, view it, assemble parts as required, then generate any drawings which are required. It should be noted that for many uses of Pro/E, complete drawings are never created. A typical design cycle for a molded plastic part might consist of the creation of a solid model, export of an SLA file to a rapid prototyping system (stereolithography, etc.), use of the SLA part in hands-on verification of fit, form, and function, and then export of an IGES file to the molder or toolmaker. A toolmaker will then use the IGES file to program the NC machines which will directly create the mold for the parts. In many such design cycles, the only print created will be an inspection drawing with critical and envelope dimensions shown.
MODEL OF CAR BUMPER
BOBY KIT BUMPER Modified cars often now have a full body kit rather than just a front and rear bumper. These kits act as a skirt around the entire body of the car and improve performance by reducing the amount of air flowing underneath the car and so reducing drag. Due to each car's specifications, these have to be specially purchased and can be made from thermoplastic, like a standard bumper, or even out of carbon fiber. CARBON FIBRE BUMPER Carbon fiber body work is normally the thing of supercars, but many car companies, and specialist modifiers, are starting to use it for replacement body part on everyday cars. This is because it is very light and is safe during a crash. It is, however, a lot more expensive than normal thermoplastic.
The above image shows assembly of car bumper with regular damper pad
STEEL BUMPER Originally plated steel was used for the entire body of a car, including the bumper. This material worked well, as it was very strong in a crash, but it was very heavy and dented performance. As car engine design has improved, steel bumpers have pretty much disappeared for anything except classic cars. Replacing one involves a lot of searching for scrap cars or having one specially made.
The above image shows assembly of car bumper with honey comb damper pad
INTRODUCTION TO CREO2.0 (PRO/ENGINEER) Creo2.0 (PRO/ENGINEER)is a feature based, parametric solid modeling program. As such, it's use is significantly different from conventional drafting programs. In conventional drafting (either manual or computer assisted), various views of a part are created in an attempt to describe the geometry. Each view incorporates aspects of various features (surfaces, cuts, radii, holes, protrusions) but the features are not individually defined. In feature based modeling, each feature is individually described then integrated into the part. The other significant aspect of conventional drafting is that the part geometry is defined by the drawing. If it is desired to change the size, shape, or
The above image shows honey comb structure damper pad
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International Journal of Research and Innovation (IJRI)
IMPACT LOAD CONDITIONS Speed1=100kmph For 100kmph&150kmph FS=1/2mv2 F=1/2(mass)(velocity)2 /s(slowdown) F=force acting on car bumper M=mass of the vehicle (1950) V=velocity in m/s S=slow down distance=0.5m 1.For 100kmph(27.7)velocity =100*1000/3600=27.7m/s F=1/2(2000)(27.7)2/(0.5)=1534.580kn =1534580n Pressure=1534580/Area174159484=13.49n/mm2=MPA Speed2=150kmph For150KMPH(41.55)(Velocity) =150*1000/3600=41.55 =F=1/2(2000)(41.55)2/(0.5)=20.325MPA
The above image shows displacement
MATERIALS AND BOUNDARY CONDITIONS ALLOY STEEL E-GLASS EPOXY S-GLASS EPOXY RUBBER NITINOL (memory shape alloy)
STRUCTURAL ANALYSIS OF CAR BUMPER WITH DAMPER AT SPEED 1
The above image shows imported model
The above image shows strain
MATERIAL E- GLASS AND RUBBER
The above image shows stress
MATERIAL S- GLASS AND RUBBER
The above image shows meshed model
MATERIAL STEEL AND RUBBER
The above image shows stress
The above image shows stress
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International Journal of Research and Innovation (IJRI)
STRUCTURAL ANALYSIS OF CAR BUMPER WITH DAMPER AT SPEED 2 MATERIAL STEEL AND RUBBER
MATERIAL E- GLASS AND RUBBER
The above image shows stress The above image shows stress
MATERIAL E- GLASS AND RUBBER
MATERIAL S- GLASS AND RUBBER
The above image shows stress The above image shows stress
MATERIAL S- GLASS AND RUBBER
STRUCTURAL ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 2 MATERIAL STEEL AND RUBBER
The above image shows stress
STRUCTURAL ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 1 MATERIAL STEEL AND RUBBER
The above image shows stress
The above image shows stress
MATERIAL E- GLASS AND RUBBER
The above image shows stress
MATERIAL S- GLASS AND RUBBER
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International Journal of Research and Innovation (IJRI)
STRUCTURAL ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 1 MATERIAL S- GLASS AND NITINOL
The above image shows strain
The above image shows stress
GRAPHS
The above image shows displacement
The above image shows displacement graph
STRUCTURAL ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 2 MATERIAL S- GLASS AND NITINOL
The above image shows strain graph
The above image shows stress
IMPACT ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 2 MATERIAL S- GLASS AND NITINOL
STRUCTURAL ANALYSIS Car bumper plain dumper pad steel
E glass
S glass
Speed1
Speed2
Speed1
Speed2
Speed1
Speed2
Stress
39.58
59.67
40.31
60.77
40.14
60.15
Displacement
1.36
2.06
3.95
5.96
0.329
0.49
Strain
0.0109
0.0165
0.0316
0.047
0.0026
0.0039
Honey comb
The above image shows stress
Stress
32.97
50.17
33.69
50.78
33.59
50.64
Displacement
1.35
2.07
3.97
5.99
0.3314
0.49
Strain
0.011
0.00013
0.00024
0.00037
2.100082e-5
3.16676e-5
Car bumper (s glass) & dumper (memory shape alloy) Speed 1
Speed 2
Stress
20.09
40.11
Displacement
0.206
0.395
strain
1.30751e-5
2.5085e-5
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International Journal of Research and Innovation (IJRI)
CONCLUSION This thesis work is done to determine about “reduction of impact effect on car bumper using honey comb technology�. Data collection and literature survey is done for the methodology. As per literature survey 34% safety can be increased. 3D models are prepared for further analysis approach. Structural analysis is done on general model to evaluate the result for the comparison purpose. Structural analysis is done on bumper by changing the material to CRFP (carbon reinforced fiber polymers). This material is choose due to its higher yield and compressive strength with in low density/weight. Analysis was conducted by implementing rubber & memory shape alloy blocks with honey comb structure instead of plain pad. Impact analysis is done on the selected model to determine FOS of car bumper at high speed collision. As per the analytical results this project concludes that car bumper with S-Glass epoxy (CRFP) along with NITINOL honey comb pad work better than previous models and it increases passenger safety by 70% (while comparing FOS). Note: S-glass is a low density carbon material with higher structural stability. Honey comb technology is widely used in Aerospace domine due to its higher strength at very low volume of material (low weight due to honey comb cuttings). NITINOL is basically a stress based memory shape alloy which regains its original state/shape at the removing stress/load. This material is widely used in dampers. REFERENCES 1). Material selection of polymeric composite automotive bumper beam using analytical hierarchy process(1) A. Hambali1, s. M. Sapuan1, n. Ismail1, y. Nukman2 1. Department of mechanical and manufacturing engineering, universiti putra malaysia, 43400 Upm serdang, selangor, malaysia; 2. Department of engineering design and manufacture, university of malaya, 50603 Kuala lumpur, malaysia 2). Research on the crash safety of the car bumper base on the different standards(2) Q. H. Ma 1, c. Y. Zhang 2, s. Y. Han 3 and z. T. Qin4 1 Shanghai univ engn sci, college of automotive engineering, Shanghai 201620, peoples r china 2 Shanghai univ engn sci, college of mechanical engineering Shanghai 201620, peoples r china 3). Effect of the strengthened ribs in hybrid toughened kenaf/ glass epoxy composite bumper beam(3) M.M. Davoodi 1, s.M. Sapuan 1, aidy ali 1, d. Ahmad 2 1. Department of mechanical and manufacturing engineering, universiti putra malaysia, 43400 upm serdang, Selangor, malaysia 4).Influence of natural long fiber in mechanical, thermal and recycling properties of thermoplastic composites in automotive components (4) S. Jeyanthi* and j. Janci rani Department of automobile engineering, mit, anna university, chennai, india 5). Impact analysis on car bumper by varying speeds using materials abs plastic and poly ether imides by finite element analysis(5) Pradeep kumar uddandapu assistant professor ,dept of
mechanical engineering, k.S.R.M college of engg, kadapa, andhra pradesh, india 6).Impact analysis of a car bumper for various speeds using Carbon fiber reinforced poly ether imide and s2 Glass epoxy materials by solid works software(6) 1V.Mohan srikanth, 2k.Venkateswara rao, 3m.Sri rama murthy 1Sir c.R.Reddy college of engineering, eluru, ap, india 7).Design of the crash deterrent bumper for heavy vehicle to car collision Hrishikesh gadage, siddharth dhamke and pravin jadhav School of mechanical and building science, vit university, vellore, india. E-mail: hrishikesh.Bapusaheb2013@vit.Ac.In, dhamkesiddharth.Vinayak2013@vit.Ac.In Pravin.Dnyaneshwar2013@vit.Ac.In 8). Impact analysis of front bumper (8) Mr. Nitinoln s. Motgi prof. S. B. Naik prof.P.R.Kulkarni Me design –ii, walchand instituteof technology,solapur (india) Associate professor, walchand Institute of technology, solapur(india) Associate professor, walchand
author
M.Arun kumar Research Scholar, Department Of Mechanical Engineering, HyderabadInstituteOf Technology And Management, Hyderabad,India
Y Anil Reddy (project Guide) Assistant professor Department Of Mechanical Engineering, HyderabadInstituteOf Technology And Management, Hyderabad,India
Godi Subba Rao, (HOD) Professor,Department Of Mechanical Engineering, HyderabadInstituteOf Technology And Management, Hyderabad,India
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