REDUCTION OF IMPACT EFFECT ON CAR BUMPER USING MEMORY SHAPE ALLOY PADS.
- 1. 130 International Journal of Research and Innovation (IJRI) International Journal of Research and Innovation (IJRI) 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 *Corresponding Author: M.Arun Kumar, Research Scholar, Department of Mechanical Engineering, Hy- derabad 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, gen- erally 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) mem- ory shape alloy which is used as damper strings. The following process will be followed to increase passen- ger’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 materi- als. 4)Honey comb structure pad with rubber and memory shape alloy will be analyzed to determine impact condi- tions. 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 occu- pants 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 Admin- istration (NHTSA) issued the country's first regulation ap- plicable to passenger car bumpers. Federal Motor Vehicle Safety Standard No. 215 (FMVSS 215), "Exterior Protec- tion," took effect on 1 September 1972 — when most au- tomakers 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 subject- ed 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 includ- ed the costs and benefits of implementation, the stand- ard'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 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 expec- tation 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. 1401-1402
- 2. 131 International Journal of Research and Innovation (IJRI) a variety designs. They ranged from non-dynamic ver- sions 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-per- hour (8 km/h) with no damage to the car's lights, safety equipment, and engine. This often meant additional over- all 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 bump- er, as they are cheap to manufacture, easy to fit and ab- sorb more energy during a crash. A majority of car bump- ers 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 ther- moplastic, with a range of fittings designed for different models. 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 perfor- mance by reducing the amount of air flowing underneath the car and so reducing drag. Due to each car's speci- fications, 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 super- cars, but many car companies, and specialist modifiers, are starting to use it for replacement body part on every- day cars. This is because it is very light and is safe during a crash. It is, however, a lot more expensive than normal thermoplastic. 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 search- ing for scrap cars or having one specially made. 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 conven- tional drafting (either manual or computer assisted), vari- ous 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 in- tegrated into the part. The other significant aspect of con- ventional drafting is that the part geometry is defined by the drawing. If it is desired to change the size, shape, or 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 mod- eling, the features are driven by the dimensions (param- eters). To modify the diameter of a hole, the hole diameter parameter value is changed. This automatically modifies the feature wherever it occurs - drawing views, assem- blies, etc. Another unique attribute of Creo2.0 (PRO/EN- GINEER)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 The above image shows assembly of car bumper with regular damper pad The above image shows assembly of car bumper with honey comb damper pad The above image shows honey comb structure damper pad
- 3. 132 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 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 meshed model MATERIAL STEEL AND RUBBER The above image shows stress The above image shows displacement The above image shows strain MATERIAL E- GLASS AND RUBBER The above image shows stress MATERIAL S- GLASS AND RUBBER The above image shows stress
- 4. 133 International Journal of Research and Innovation (IJRI) STRUCTURAL ANALYSIS OF CAR BUMPER WITH DAMPER AT SPEED 2 MATERIAL STEEL AND RUBBER The above image shows stress MATERIAL E- GLASS AND RUBBER The above image shows stress MATERIAL S- GLASS AND RUBBER The above image shows stress STRUCTURAL ANALYSIS OF CAR BUMPER WITH HON- EY COMB DAMPER AT SPEED 1 MATERIAL STEEL AND RUBBER The above image shows stress MATERIAL E- GLASS AND RUBBER The above image shows stress MATERIAL S- GLASS AND RUBBER The above image shows stress STRUCTURAL ANALYSIS OF CAR BUMPER WITH HON- EY COMB DAMPER AT SPEED 2 MATERIAL STEEL AND RUBBER The above image shows stress MATERIAL E- GLASS AND RUBBER The above image shows stress MATERIAL S- GLASS AND RUBBER
- 5. 134 International Journal of Research and Innovation (IJRI) STRUCTURAL ANALYSIS OF CAR BUMPER WITH HON- EY COMB DAMPER AT SPEED 1 MATERIAL S- GLASS AND NITINOL The above image shows stress The above image shows displacement STRUCTURAL ANALYSIS OF CAR BUMPER WITH HON- EY COMB DAMPER AT SPEED 2 MATERIAL S- GLASS AND NITINOL The above image shows stress IMPACT ANALYSIS OF CAR BUMPER WITH HONEY COMB DAMPER AT SPEED 2 MATERIAL S- GLASS AND NITINOL The above image shows stress The above image shows strain GRAPHS The above image shows displacement graph The above image shows strain graph 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 Displace- ment 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 Stress 32.97 50.17 33.69 50.78 33.59 50.64 Displace- ment 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
- 6. 135 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 technol- ogy”. Data collection and literature survey is done for the meth- odology. 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 com- pressive strength with in low density/weight. Analysis was conducted by implementing rubber & mem- ory shape alloy blocks with honey comb structure instead of plain pad. Impact analysis is done on the selected model to deter- mine 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 NITIN- OL honey comb pad work better than previous models and it increases passenger safety by 70% (while compar- ing 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 engi- neering, 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 engineer- ing, Shanghai 201620, peoples r china 2 Shanghai univ engn sci, college of mechanical engineer- ing 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 engi- neering, 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 univer- sity, chennai, india 5). Impact analysis on car bumper by varying speeds us- ing 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 us- ing 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, dham- kesiddharth.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