Virtual baja 2016 17227 tezpur university_presentation
-
Upload
bishal-das-purkayastha -
Category
Automotive
-
view
50 -
download
1
Transcript of Virtual baja 2016 17227 tezpur university_presentation
Virtual BAJA SAEINDIA 2016
TEAM BRAHMAPUTRA TEZPUR UNIVERSITY
TEAM ID-17227
• TEAM BRAHMAPUTRA • TEZPUR UNIVERSITY
TECHNICAL AND PERFORMANCE SPECIFICATION
• Overall width : 60.575 inch
• Overall length : 85.817 inch
• Rear track width : 52.482 inch
• Front track width : 52.482 inch
• Wheel base : 62.243 inch
• Ground clearance : 11.762 inch
• Maximum speed : 41 kmph
• Kerb weight : 338.879 kg
• Passenger capacity : One seater
• Centre of gravity height : 13.855 inch
• Vehicle type : All terrain vehicle
• Stopping distance(40 kmph): 13.04 meter
• Vehicle height from ground : 54.607 inch
• Engine : Briggs & Stratton 10 HP OHV
Intek four stroke , 305 cc , air
cooled
Fig 2: VIEW FROM BACK Fig 1: ISOMETRIC VIEW
Fig 3: SIDE VIEW Fig 4: FRONT VIEW
ROLL CAGE DESIGN AND ERGONOMICS• Material used for primary and secondary members: AISI 4130 Chromium Molybdenum cold rolled seamless tube• Carbon content: 0.30%• Outer diameter of primary and secondary members, D0 = 25.4 mm• Thickness of primary and secondary members: 3 mm• Internal diameter, Di = 19.4 mm• Yield strength of AISI 4130, Sy=460 MPa• Young’s modulus, Ex = 205GPa
• Total length of tube = 38.43 metres• Overall weight of roll cage = 41.314 kg ≈ 412.996 N
1> Calculation for Bending Strength : Polar moment of inertia, I= 3.14*(D0
4 - Di
4)/64 = 13471.805 mm4
Distance to extreme fiber, c = 25.4/2 = 12.7 mm ∴ Bending Strength = SyI/c = 487.955 N-mAnd, Bending Stiffness=ExI = 2761.720 N-m2
2>Ergonomics specification:a) Spacious enough to accommodate a 95th percentile male and 5th percentile femaleb) Comfortable seating and viewing angle. c) Suitable reach limitd) Better visibilitye) Clearance requirements are fulfilledf) Easy entrance and exit.
Fig 5: ROLL CAGE DESIGN
Fig 6: ERGONOMICS- LATERAL CLEARANCEFig 7:ERGONOMICS- HEAD CLEARANCE
CAE BASIC PROCESS AND ITS APPLICATIONS
Fig 10: FRONT IMPACT (STRESS)
Fig 13: SIDE IMPACT(STRESS)
Fig 15: ROLLOVER(STRESS)
Fig 9: TORSIONAL(STRESS)
CALCULATIONS INVOLVED:Estimated mass of vehicle=338.879 kgLet, G=Estimated mass of vehicle × gWhere,g=accelaration due to gravity ≈ 10 m/s2
Hence,G=338.879 × 10 = 3388.79 NNet Force applied= 4G= 3388.79 × 4= 13555.16 N
ROLL CAGE ANALYSIS
Fig 8: FRONT IMPACT(DEFORMATION)
Fig 11:SIDE IMPACT(DEFORMATION)Fig 12:ROLLOVER(DEFORMATION)
Fig 14:TORSIONAL(DEFORMATION)
Results :Front impact: Max. deform.=1.726 mm;Min. deform=0 mm;Max. stress=609 MPa;Min stress=25.794 Pa Side impact: Max deform=0.64 mm;Min deform.=0 mm;Max stress=661.92 MPa ;Min stress=0.069 PaRollover:Max. deform.=0.72 mm ;Min. deform=0 mm;Max stress=288.38 MPa ; Min stress= 0.386 PaTorsional :Max. deform=12.754 mm;Min deformation=0 mm;Max stress=1315.7 MPa;Min stress=0.475 Pa
SUSPENSION PARAMETER FRONT REAR
Suspension type Double Wishbones
Suspension material AISI 4130
Natural frequency 2.09 Hz 2.35 Hz
Spring Stiffness 16.11N/mm
Spring material STEEL 17-7 A313
Motion Ratio 0.491
Damper Ratio 0.35
Max. Suspension Travel 135 mm 220 mm
Bounce Frequency 1.60 Hz
Caster (deg.) 7.0 (+ve)
Camber (deg.) 0-0.5(+ ve)
Kingpin Inclination (deg.) 9.37
Toe (deg.) 0
Sprung Mass 338.879 Kg
Un –Sprung Mass 48 Kg
Toppling Speed(at min. turning radius)
20.16 Km/h
Roll Centre Height 195.834 mm 225 mm
KNUCKLE STRESS ANALYSYS
EXPLODED VIEW ASSEMBLY
HUB STRESS ANALYSYS
A-ARM STRESS ANLYSIS
Camber angle v/s Wheel Travel
Roll Centre Height v/s Wheel Travel
Camber v/s Steer S
• Hydraulically actuated disc brake on all four wheels lock simultaneously
• Tandem master cylinder
• 2POT floating calliper
• X-split braking system
• Pedal ratio = 6:1
• Pedal force = 120 N
• Brake fluid = DOT4
BRAKES
Parts SpecificationRotor(stainlessSteel)
Polaris sportsman500
O.D -- 9” I.D – 5.5”
Master cylinder(tandem)
Polaris sportsman 500
0.75”
Calliper cylinder( 2pot)
Polaris sportsman500
1”
Performance Value
Torque per wheel 93.72 Nm
Total brake force 1283.39 N
Deceleration 4.73 m/s2
Stopping distance 13.04 m
Wt. transfer 36%
Disc brake and calliper assembly
Dynamic wt. On front axel
2258.29 N
Dynamic wt. On rear axel 1062.73 N
STEERING AND WHEEL GEOMETRYPARAMETER VALUES
TYPE RACK & PINION
INSIDE WHEEL ANGLE 45 degree
OUTSIDE WHEEL ANGLE 28.48 degree
ACKERMANN ANGLE 39.75 degree
WHEEL BASE 62.243 inch.
TRACK WIDTH 52.482 inch.
TURNING RADIUS 3.31 m
RACK LENGTH 16 inch.
RACK TRAVEL(lock to lock)
6.5 inch.
End to end 390 degree
ACKERMANN PERCENTAGE
72.48 %
STEERING RATIO 8.4 : 1
TORQUE 4.05 N-m
INSIDE WHEEL ANGLE FOR 100% ACKERMANN
22.79
Item Description & Dimensions
Front tire Carlisle AT489 - 25 x 8-12
Rear tire Carlisle AT489 - 25 x 11-12
Ackermann Geometry
Steering system
Wheel assembly
RPM(Engine)
Engine Torque(Nm)
Total Gear Ratio
Torque on Wheel(Nm)
Traction(N)
Velocity(km/hr)
Resistive forces(N)
Acceleration(m/s2)
1800 18.03 39.90 633.07 1993.92 5.40 443.81 3.432000 18.71 36.69 604.10 1902.66 6.52 444.03 3.232200 18.98 33.50 559.53 1762.30 7.86 444.37 2.922400 19.32 30.30 515.15 1622.52 9.48 444.85 2.612600 19.52 27.09 465.34 1465.64 11.48 445.59 2.262800 19.67 23.94 414.40 1305.17 14.01 446.70 1.903000 19.60 20.70 357.03 1124.52 19.96 448.28 1.503200 19.38 17.50 298.50 940.01 21.89 451.61 1.083400 19.11 14.29 240.31 756.88 28.48 457.35 0.663600 18.84 11.09 183.86 579.09 38.84 469.40 0.243800 18.11 11.09 176.74 556.66 41.01 472.43 0.19
POWERTRAINEngine specificationsBriggs and Stratton 10 HP OHV IntekDisplacement : 305ccMax Power : 7.187 kW @ 3800 rpmMax Torque : 19.66 Nm @ 2810 rpm
Transmission Unit Polaris P90 belt CVT
Primary(input) : 184 mm Secondary(o/p): 241 mm Low ratio :: 3.83:1 High ratio :: 0.76:1
Reversing Mechanism Tire Size (25’’*8”*13”)
Powertrain Layout
ENGINE(Crankshaft)
Reversing mechanism
(Engaged/Disengaged)
CVT SPROCKET-1 (2:1)
SPROCKET-2 (2.625:1)
LIMITED SLIP DIFFERENTIAL (Final Drive:
3.16)
WHEELS
TABLE: VELOCITY AND ACCELERATION AT OUTPUT
COST AND WEIGHT ANALYSIS PI-CHARTParts Cost(Rs.) Weight(kg)
chassis 24,400 67.276
Front tire with rim
30,000 49.16
Rear tire with rim
38,000 50.66
Suspension system
88,000 30.196
Braking system 34,000 35.844
Steering system
20,000 10.5
engine 20,000 26.4
Transmission 1,10,000 46.064
Safety feature 11,200 17.689
electrical 52,200 5
Total 4,27,800 338.789
Cost
chasis front wheelrear wheel suspension systembraking system steering systemengine transmissionsafety feature electrical
Weight(in kg)
PROJECT PLAN
VALIDATION PLANITEM Failure Mode Failure Cause Failure Effect Preventive Action
Frame Bending and breaking of frame
Axial stress exceeds yield stress of material due to excess load and impact loading
Overall damage to roll cage. Frame breaks or bends. Driver’s safety is endangered
Material with appropriate /high factor of safety(FOS) , effective design and analysis; constant testing
CVT Tuning Improper mounting Sensitive mountingRack & Pinion Leaking of fluid,
Loosening of lug nutObstruction in movement of pinion over rack, damage to components
Steering failure;Safety of driver andothers compromised
Verification of desired specification and testing
A-arm Bending, Breakage,cracks, structuraldamage
Axial stress exceeds yielding stress of materialdue to excess load andimpact loading
Damage to suspension system and rough operation of the vehicle
Material with high FOS and according to vehicle specifications; effective design and analysis
Spring Spring fractures and fail Due to faulty choice of springs, spring fails due to loads exceeding the yield stress of the material
Damage to suspension system and rough of the vehicle
Choose springsaccording to vehicle loads and other specification
Shock Absorber Leaking of suspension oil
Cylinder damage due to foreignbody/debris
Damage to suspension system and rough of the vehicle
Verification ofspecificationsand testing
pedals Structural failure die to fatigue, bending and breaking
Excess load by driver causes axial load to exceed yield strength of material
Brake failure Choose materialwith high FOS and carefultesting should be done
Braking system Mechanical failure Not sufficientbraking force
Damage to vehiclein undesiredcircumstances
Choose materialwith high FOS and careful testing
WORKSHOP FACILITIES AND TEAM COMPOSITION
Faculty advisor Dr. Partha Pratim Dutta
Faculty advisor Dr. Santanu Sharma
Chassis design and analysis
1722702,1722707
Ergonomics 1722711, 1722710
Suspension and simulation
1722713,1722716
Brake 1722701,1722708
Steering and wheel geometry
1722706,1722714
Transmission 1722704,1722715
Electrical system 1722718,1722720
Engine fuel and exhaust system
1722709,1722712
Marketing 1722717,1722721
Material procurement 1722703,1722705