sun'skaar - final report on capstone project
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CERTIFICATE
I hereby certify that the work which is being presented in the Capstone project entitled
“SUN’SKAAR (Solar Car)” in partial fulfillment of the requirement for the award of
degree of Bachelor of technology and submitted in Department of Mechanical Engineering,
Lovely Professional University, Punjab is an authentic record of my own work carried out
during period of Capstone under the supervision of Pankaj Saini, Asst. Professor,
Department of Mechanical Engineering, Lovely Professional University, Punjab.
The matter presented in this report has not been submitted by me anywhere for the award of
any other degree or to any other institute.
Date: ………….. VIKAS KUMAR, MUKESH ADLAK,
PRATUL VISHWAKARMA, MAHESH NYATI,
RAJEEV KURREE, SAGAR CHIKKA
This is to certify that the above statement made by the candidate is correct to best ofmy knowledge.
Date: ………….. PANKAJ SAINI
BIKASH KANT
MANDEEP SAINI
Mentor
Department of Mechanical
L ov e ly P rof e s si o n a l U n i v er si t y Ja
Engineering
l a n d h a r , P unjab
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ACKNOWLEDGEMENT
I would like to place on record my deep sense of gratitude to Mr. Pankaj Saini Sir,
Assistant Professor at Lovely Professional University, Jalandhar for his generous guidance,
help and useful suggestions.
I express my sincere gratitude to Mr. Bikash Kant Sir, Assistant Professor at Lovely
Professional University, Jalandhar for his stimulating guidance, and continuous encouragement
.
I also wish to extend my thanks to Mr. Mandeep Saini Sir, Assistant Professor at
Lovely Professional University, Jalandhar for his stimulating guidance, and continuous
encouragement.
I am extremely thankful to Mr. Gurpreet Singh Phul Sir, HOS, Lovely Professional
University Jallandhar, for valuable suggestions and encouragement and for providing the
opportunity to get the knowledge.
.
Date: ……………… VIKAS KUMAR, MUKESH ADLAK,
PRATUL VISHWAKARMA, MAHESH NYATI,
RAJEEV KURREE, SAGAR CHIKKA
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TABLE OF CONTENTS
Page No.
Acknowledgement i
Table of Contents ii-iii
List of Tables iv
List of Figures v-vi
List of Nomenclature vii
List of Abbreviations vii
Chapter 1: Introduction 1
1.1: Objectives 1
Chapter 2: Literature Review 2-3
Chapter 3: Future Scope of the Study 4
Chapter 4: Research Methodology 5-12
4.1: 200+ km mileage 5
4.2: 1kw electricity generation by Sun 6-7
4.3: Aerodynamic design & great look for the vehicle 8
4.4: 40 km/h speed 9-12
Chapter 5: Production Plan / Gantt Chart 13-15
Chapter 6: Research & Experimental work done 16-62
6.1: Design & Bodyworks 16-21
6.1.1: Chassis 16-20
6.1.1.1: Material Selection 16
6.1.1.2: Dimensional Specifications 16
6.1.1.3: Chassis Loading & Simulation 17-20
6.1.2: Bodyworks 21
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6.2: Power Transmission 22-26
6.2.1: Formulas 22-23
6.2.2: Calculations 24-26
6.3: Suspension 27-35
6.4: Braking & Wheels 36-43
6.4.1: Braking 36-40
6.4.2: Wheels 40-43
6.5: Steering 44-56
6.5.1: Steering Dynamics 44-50
6.5.2: Steering mechanism 51-52
6.5.3: Ackerman Steering Geometry 52-56
Chapter 7: Cost Report 57-62
7.1: ECE Components 57-59
7.2: Mechanical Components 60-62
Chapter 8: Results & Discussion 63-66
8.1: Detail Specifications & Features 63-66
Chapter 9: Conclusion & Summary 67-68
9.1: Highlights 67
9.2: Advantages 67-68
Chapter 10: Pictures / Images 69-72
References
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iv
List of Tables
Table Title Page
5.1 Production plan / Gantt chart………………………………………………….13
6.1 Dimensions for Suspension calculation………………………...…..................27
6.2 A-arm data…………………………………………………............................ 27
6.3 Spring specification. ........................................................................................ 32
6.4 Data for braking calculation ….. .....................................................................36
6.5 Braking Specification........................................................................................39
6.6 Dimensions of vehicle………………………………………………………...54
6.7 Formulaes for Steering…………………………………………….……….....54
7.1 Cost Report for Electronics components………………………….…………..57
7.2 Cost report for Mechanical components………………………….…………...60
8.1 Engine & Transmission specification…………………………………………63
8.2 Performance data……………………………………………………………...64
8.3 Other specification…………………………………………………………….64
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LIST OF FIGURES
FIGURE CONTENT Page no.
Fig 4.1- Solar cells 6
Fig 4.2- CAD model of SunsKaar in Solidworks 8
Fig 4.3- Hall sensor test circuit 10
Fig 4.4- Hall sensor test(Pull Up) 10
Fig 4.5- Oscilliscope image 11
Fig 6.1- Front impact (Horizontal displacement) 17
Fig 6.2- Static loading (vertical bending) 18
Fig 6.3- Rear Impact (horizontal deflection) 19
Fig 6.4- Torsion Test 20
Fig 6.5- A Arm data 27
Fig 6.6- Lateral weight transfer during the Left turn of vehicle 28
Fig 6.7- Longitudnal Weight transfer During Braking 29Fig 6.8- Cornering force 30
Fig 6.9- Camber calculation 31
Fig 6.10-Tire axis system 31
Fig 6.11- Spring Deflection due to load applied: 32
Fig 6.12- King pin inclination 33
Fig 6.13- Geometry of front suspension 34
Fig 6.14-Geometry of front suspension(angle calculation) 34
Fig 6.15a- Mounting of front suspenion(left) 35
Fig 6.15b- Mounting of front suspenion(right) 35
Fig 6.16- Geometry of Rear Suspension: (leaf spring) 35
Fig 6.17- Tyre rating 41
Fig 6.18- A front-wheel-steering vehicle and the Ackerman condition. 44
Fig 6.19- A front-wheel-steering vehicle and steer angles of the inner and outer wheels 45
Fig 6.20- Equivalent bicycle model for a front-wheel-steering vehicle. 49
Fig 6.21- Eff ect of w/l on the Ackerman condition for front-wheel-steering vehicles 50
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Fig 6.22- A sample parallelogram steering linkage and its components. 51
Fig 6.23- A rack-and-pinion steering system 52
Fig 6.24- Ackermans Angle 53
Fig 10.1- Sunskaar at Auto expo 69Fig 10.2- Sunskaar interior 70
Fig 10.3- Pvc modelling 71
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NOMENCLATURE
English Symbols
θ Angle
Fd Drag Force
ƥ Density
π Constant
µ Friction Coefficient
ABBREVIATIONS
ATDC After Top Dead Center
BDC Bottom Dead Center
BTDC Before Top Dead Center
CA Crank Angle
CAD Computer Aided Design
CCS Combined Charging System
CFD Computational Fluid Dynamics
CO Carbon Monoxide
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Chapter 1
Introduction
________________________________________________________
A car made by innovative engineers of Lovely Professional University which can
contribute its role in the daily life of a common man. Our Solar Car deserves to be among
the highest mileage vehicle currently present in Indian market which is made with
minimum expenditure having high efficiency.
Our car gets energy from the ultimate power source “The SUN” and can be charged by
home electricity. Home appliances can also run using the energy from our car. We are also
introducing some hi-tech features in it which can be useful for safety & security purposes.
1.1 Objectives:
1)
Start a new chapter in the field of renewable energy resources.
2) Introduce an ecofriendly option for automotive sector.
3)
Produce safe and clean energy.
4) To provide a safer and clean environment.
5) Increase the life of Human being.
6) Create a better future for ourselves.
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Chapter 2
Literature Review
________________________________________________________
Solar cars combine technology typically used in the aerospace, bicycle, alternative
energy and automotive industries. The design of a solar vehicle is severely limited by the
amount of energy input into the car. Most solar cars have been built for the purpose of solar car
races. Since 2011 also solar-powered cars for daily use on public roads are designed List of
solar cars (with homologation).
Solar cars are often fitted with gauges as seen in conventional cars. To keep the car
running smoothly, the driver must keep an eye on these gauges to spot possible problems. Cars
without gauges almost always feature wireless telemetry, which allows the driver's team to
monitor the car's energy consumption, solar energy capture and other parameters and free the
driver to concentrate on driving.
Solar cars depend on PV cells to convert sunlight into electricity. Unlike solar thermal
energy which converts solar energy to heat for either household purposes, industrial purposes
or to be converted to electricity, PV cells directly convert sunlight into electricity.[1] When
sunlight (photons) strike PV cells, they excite electrons and allow them to flow, creating an
electrical current. PV cells are made of semiconductor materials such as silicon and alloys of
indium, gallium and nitrogen. Silicon is the most common material used and has an efficiency
rate of 15-20%.
During the 1990s, regulations requiring an approach to "zero emissions" from vehicles
increased interest in new battery technology. Battery systems that offer higher energy density
became the subject of joint research by federal and auto industry scientists.
Solar cars were first built by universities and manufacturers. The sun energy collector areas
proved to be too large for consumer cars, however that is changing. Development continues
on solar cell design and car power supply requirements such as heater or air-conditioning fans.
http://en.wikipedia.org/wiki/Solar_car#cite_note-1http://en.wikipedia.org/wiki/Solar_car#cite_note-1http://en.wikipedia.org/wiki/Solar_car#cite_note-1http://en.wikipedia.org/wiki/Solar_car#cite_note-1
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The Stanford Solar Car Project is America's top solar car team. The project began in
1989 and is an entirely student-run, non- profit organization fueled by its members’ passion for
environmentally sustainable technology. The team designs and builds solar powered cars to
race in the 2000 mile long World Solar Challenge in the Australian Outback.
Powered solely by the sun, this single-seat race vehicle uses the same amount of energy
that it takes to power a hair-dryer. On a closed test course, infimum reached speeds of over 105
mph. Building the solar car is a two year project that takes over 100 student team members and
more than 1 million dollars.
That's the allure of the solar car, in many ways the Holy Grail of clean energy transport.
It came one step closer to reality this week with Ford Motor debuting its C-MAX Solar Energy
Concept car at Consumer Electronics Show (CES) 2014 in Las Vegas. (Related Quiz: What
You Don't Know About Cars and Fuel)
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Chapter 3
Future Scope of the Study
________________________________________________________
Solar Electric Cars are the future of world movement. The best feature of this car is that
it is the pollution free. Solar car can save 3 Rs. Per km in comparison of petrol cars so it can
save the big chunk of money for middle class people.
3.1 Utility:
1) It works on clean energy.
2) Pollution free.
3)
Economic.
4)
Cost Efficient.
3.2 Uniqueness:
1) Works on Solar Energy.
2) Mileage greater than any other vehicle present in India.
3)
Clean and pollution free.
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Chapter 4
Research Methodology
________________________________________________________
Research work on Solar Car started with following targets :
4.1 200+ km mileage.
4.2 1kw electricity generation by Sun.
4.3 Aerodynamic design & great look for the vehicle.
4.4
40 km/h speed.
4.1 200+ km mileage:
Mileage of vehicle depends on battery. So our technical team began to search
best battery with less cost, compact size, light weight & higher capacity in Ah.
We had two options first Exide and second one is Tata batteries. And we
obtained Tata Battery with following specifications :
Capacity : 80 Ah
Voltage : 12 volts
No. of Batteries : 8 (2 sets, 4 batteries in 1 set)
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4.2 1kw electricity generation by Sun:
Electricity generation depends on solar cells. The working & selection of solar cells
discussed below :
Solar cells
ANALYZING & CRYTICAL THINKING:The solar cells are selected bytaking the
following things into consideration
1)Area of the cell Fig-4.1-solar cell
2)Power delivered by the cell
3)Availability of the cell
4)Cost of the cell
5)Manufacturing nation
Here we have two main class of cells they are :
1.Monocrystalline cells
2.Polycrystalline cells
Monocrystalline cells are choosen for the following reasons:
Solar cells made of monocrystalline silicon (mono-Si), also called single-crystalline silicon
(single-crystal-Si), are quite easily recognizable by an external even coloring and uniform look,
indicating high-purity silicon.
Monocrystalline Premium Line panels have a maximum efficiency of about 15.47%,
whereas Conergy’s polycrystalline PowerPlus modules have a maximum efficiency of 14.13%.
HERE ARE FEW ADVANTAGES OF USING MONICRYSTALLINE CELLS:
LONGITIVITY:
Monocrystalline solar panels are first generation solar technology and have been around a
long time, providing evidence of their durability and longevity. The technology, installation,
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performance issues are all understood. Several of the early modules installed in the 1970′s are still
producing electricity today.
EFFICIENCY:Monocrystalline solar panels are able to convert the highest amount solar energy into
electricity, thus if your goal is to generate the maximum possible electricity at your area,
monocrystalline is an obvious choice.
Solar panels products use cadmium telluride (CdTe). Cadmium is a heavy metal that
accumulates in plant and animal tissues. Cadmium is a ‘probable carinogen‘. While Cadmium
doesn’t pose a threat while the solar panel is in service, disposing of the panels has to be done
properly, which often comes at a large cost.
“Monocrystalline cells are not harmful or hazardous to the environment.”
MORE ELECTRICITY:
Monocrystalline panels produce more electricity per m/2 than other panels.
Now by taking all the above aspects into consideration the monocrystalline cells were selected .
SPECIFICATIONS:
Per a single cell:
1)DIMENSIONS:150X150mm
2)COST:2$
3)OUTPUT VOLTAGE:0.56V
4)OUTPUT CURRENT:8A
For the whole set:
1)OUTPUT VOLTAGE:48V
2)OUT POWER:1KW(approximately)
3)NUMBER OF SETS:2
4)NUMBER OF CELLS IN EACH SET:96
5)ALLIGNMENT OF CELLS:The two sets were connected parallel to produce a voltage of 48v
and a power of 1KW.
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4.3 Aerodynamic design & great look for the vehicle:
Fig 4.2 CAD model of Sun’sKaar in Solidworks
Final Design of Solar Car has been prepared after rejection of more than 40 designs using
Solidworks & NX (Unigraphics) softwares.
Following factors were considered for final selection :
1)
6 m^2 area for solar cells for generating 1kw solar electricity.
2) Esthetics & comforts for driver & passangers.
3) Safety.
4) Easy to install solar cells.
5) Dynamic look.
6)
Easy to manufacture.
7)
Aerodynamics of vehicle.
Etc.
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4.4 40 km/h speed:
Speed & load carrying capacity of the vehicle depends on motor. Selection criteria of motor &
it’s working is discussed below :
WORKING OF BRUSHLESS DC MOTOR
Problem: The Brushless DC Motor is running incorrectly, or stops running.
Solution: A Brushless DC Motor having difficulty operating could indicate that the Hall
Sensors are bad. To check, use a resistor to pull up each Hall to 5 volts, and check each Hall
with an oscilloscope while spinning the shaft. Monitor the point between the Hall and the
resistor as pictured below in Figure 2.
Repeat this process for each individual Hall. When spinning the shaft manually, a low
and high signal should appear on the scope. Keep in mind the importance of what value is used
for the resistance; this depends on the amount of current the Hall sensors can withstand.
If this test demonstrates that the Hall Sensors are working correctly, the next step is to
check the phases of the Brushless DC Motor. Hook up the Brushless DC Motor to a controller.
With an oscilloscope, check each phase to see if a switching signal is present. If the phases do
not pose a problem, this may indicate a bearing problem, or internal shorts. If these techniques
do not seem to explain why the Brushless DC Motor is working improperly, the purchase of a
new Brushless DC Motor should be considered.
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Fig 4.3-Hall sensor test circuit
Fig 4.4-Hall sensor test(pull up)
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Fig 4.5-Oscilliscope Image
The Hall Effect uses three hall sensors within the Brushless DC Motor to help detect the
position of the rotor. This method is primarily used in speed detection, positioning, current
sensing, and proximity switching. The magnetic field changes in response to the transducer that
varies its output voltage. Feedback is created by directly returning a voltage, because the sensor
operates as an analogue transducer. The distance between the Hall plate and a known magnetic
field can be determined with a group of sensors, and the relative position of the magnet can be
deduced. A Hall sensor can act as an on/off switch in a digital mode when combined with
circuitry.
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Controller to Motor Connection
Yellow 2mm
Green 2mm Phase Wire
Blue 2mmYellow
Green Hall
Blue Effect
Red
Controller Input
Red Input wires
Black 48 V
Green ->Throtal -> input VCC
Pink->Throtal -> Output
Black->Throtal -> Ground
Yellow reverse/forward
Black
Two white wires -> limiting the speed
Grey -> Speedometer
Orange -> Dynamic Brake
Orange (Thicker wire) -> Ignition
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Chapter 5
Production Plan / Gantt Chart
The plan is divided into different phases. This is a table consists of the information
which is required in production work and the things which will be used during production.
Table 5.1 Production Plan / Gantt Chart
Sl
no.
Work Tools
required/machine
Other material Cost Mem
bersrequi
red
Days
requir ed
1) Sketching of
chassis
Plywood-1
Pencil,rubber,whites
heet,measuringsacle
27/10/13 2 2
2) Pvc modeling Hand hacksaw Clip,nails,wire,
Measuring scale
30/10/13 3 3
3) Making of
space frame
Power
cutter,handhacksaw,
welding machine
Rectangular
pipes(arrange from
inside university)
3/11/13 6 3-4
4) Cutting of
pipes
Power
cutter,handhacksaw,
filer
Cutter and grinder 5/11/13 4 2
5) Welding of
pipes
Welding machine Welding elctrodes 7/11/13 4 2
6) Chassis
finishing
Grinder Grinding wheel 8/11/13 2 1
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7) Making of A
arms
Power cutter, hand
hacksaw, welding
machine
Pipe,cutter,grinder 10/11/13 2 2
8) Hub
mounting and
tire assembly
in front
Power cutter,
welding machine
Hub of
wheel,tyre,nuts and
bolts
12/11/13 3 2
9) Transmission
assembly with
motor.
Power cutter and
welding machine
Tyre and motor hub
assembly
14/11/13 3 2
10) Tyre
mounting rear
Power cutter Hub, tyre, nuts and
bolts, with shaft
16/11/13 2 1-2
11) Brake
mounting
Power cutter Coupler, brake and
caliper, nuts & bolts
17/11/13 2 1
12) Steering
mounting
Power cutter and
welding machine
Steering assembly,
pipes, nuts and bolts
19/11/13 3 1-2
13) Seat
mounting
Power cutter Angles, nuts and
bolts, rubber tubes
20/11/13 2 1
14) Body works
frame
Wood cutter, filer thermacole, nails,
fevicol, wood
22/11/13 3-4 2
15) Body works As required Glass fibre material 20/12/13 4-5 15
16) fitting of body
works with
chassis
Power cutter and
grinder
Nuts and
bolts,rubber tubes
22/12/13
3-4 2
17) Finishing of
body works
Power cutter and
files
styrofoam,rubbertub
es,sheet metal
23/12/13 2-3 1
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18) Wiring and
innovation
As required Plastic pipes, 28/12/13 2-4 5
19) Solar panels
on body
As required Solar cells /solar
sheets,wires,
7/1/14 3 10
20) Controller
circuit
between solar
panels and
battery
As required Wires,PCB board
and electrical
components
12/1/14 2 5
21) Others As required 31/1/14 2 19
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Chapter 6
Research & Experimental work done
________________________________________________________
6.1 DESIGN & BODYWORKS:
6.1.1 CHASSIS:
IT is the backbone of any vehicle. Designed to bear all types of load whether long
duration, short duration or impact load. It contains mounting space and points for all thecomponent of the vehicle. We used ladder type of chassis with different types of pipe thickness
and diameter in different places where it is well suited. We used ladder chassis because of its
rigidity and manufacturing simplicity.
6.1.1.1 MATERIAL SELECTION:
AISI 1020 was selected for the chassis because the following stated reasons:
1. Machinability (70%)
2. Weld ability
3.
Availability
The frame or chassis can be called as skeleton of a vehicle, beside its purpose being seating
the driver, providing safety and incorporating other sub system of the vehicle.
6.1.1.2 Dimensional Specifications
Round pipe of dimension:
25.4mm O.D
2mm & 3mm THICKNESS
AISI 1020 seamless mild steel pipes, normalized at 810°
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6.1.1.3 CHASSIS LOADING AND SIMULATION
Front impact (Horizontal displacement):
Calculation:
F = (mv2-mv1)/t
Here, v2=0 ; ( since, it is assumed that after impact it will come to rest)
F = (-mv1)/t; (here negative sign indicates that direction of impact force will be approx. to the
velocity.)
Neglecting the negative sign, we have;
F=mv1/t
The time t can be written as t=2x/u + v
Here v=0 and u=v1,
Therefore, F=mv2/2x; (x is distance travelled before stopping)
Now, putting values, we have;
M = 500kg, u = 40 km/hr = 11.1m/s , x = 2m
F=15,401.25N
Fig 6.1- Front impact (Horizontal displacement)
Results:
FOS = 1.52
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Static loading (vertical bending)
Total mass assumed -> 500 kg
Now, total vertical static force including gravitational
500 x 9.87 = 4905 N
Fig 6.2- Static loading (vertical bending)
Results:
FOS = 3.04
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Rear Impact (horizontal deflection)
Force, F = (mv2-mv1)/tLet us assume that after back impact velocity gets 1.5 times more, therefore
V2=3/2 v1
F =mv1/2t
Assume that vehicle moves distance x during this change, therefore time taken to
cover this distance x,
t = 2x/ (u+v) =2x/ (2.5u)
F=(5/8)×(mu
2
/x)
Now putting values
M = 500kg, u = 40 km/hr = 11.1m/s , x = 2m
F=19,251 N
Fig 6.3- Rear Impact (horizontal deflection
Results:
FOS = 1.03
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Torsion Test
Four outer joints of back portion are fixed and opposite forces are applied at to outer
links of front portion. Force on each outer linkF=1000 N
Fig 6.4- Torsion Test
Result:
FOS = 7.75
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6.1.2 Bodyworks
Area of bodyworks -161 square feet
Material required:
high temperature wax v207, epoxy resin,curing agent(),5.8 oz fiberglass cloth 38”.
Chemical and its rates:
Chemical Rates
Epoxy resin(diglycidyle ether of bisphenol) - 160 per kg
Curing agent(diethylanilenetriamine) - 390 per liter
5.8 oz fiberglass cloth 38” - 160 per kg
high temperature wax v207 - 600 per kg
*Ratio of epoxy resin & curing agent is 10:1 (weight by volume) and it also vary according to
the curve surface.
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6.2 Power Transmission
6.2.1 Formulas:
Power :
P = TW
Where : P = Power (Watt)
T = Torque (Nm)
W = Angular Velocity (rad/sec)
Torque :
T = F.r
Where : T = Torque (Nm)
r = Wheel Radius (m)
F = Forces on Vehicle (N)
F = Rolling Friction Force + Drag Force + Force due to Inclination
o Rolling Friction Force (Fr) = µ.m.g
Where : µ = Rolling Friction coefficient = 0.02
m = Mass of Vehicle (Kg)
g = Gravity = 9.81 m/s^2
o Drag Force (Fd) = (Cd.ƥ.A.V^2)/2
Where : Cd = Drag Coefficient (depends on design)
ƥ = Air Density = 1.2 Kg/m^3
A = Area (Front) (m^2)
V = Velocity of Vehicle (m/s) = R.W
o Force due to Inclination = m.g.sinθ
Where : m = Mass (Kg)
g = Gravity = 9.81 m/s^2
θ = Inclination Angle
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Angular Velocity :
W = (2.π.N)/60 = V/r
Where : π = 3.14
N = RPM of Wheel
Gear Ratio :
R = N1/N2 = T2/T1
Where : N1 = RPM of motor or engine
N2 = RPM of wheel
T2 = Torque to wheel = No. of teeth of gear/sprocket 2
T1 = Torque of motor or engine = No. of teeth of gear/sprocket 1
Acceleration :
a = F/m
Where : F = Net force on vehicle (N)
m = Mass of vehicle (Kg)
a = Acceleration of vehicle (m/s^2)
Time taken to attain top speed :
t = (V2 – V1)/a
Where : a = Acceleration of vehicle (m/s^2)
V2 = Final velocity of vehicle (m/s)
V1 = Initial velocity of vehicle (m/s)
Climbing ability :
F = T2/r = Fr + Fd + mgsinθ
θ = ?
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6.2.2 Calculations:
Force on vehicle :
F = Fr + Fd + mgsinθ
F = µmg + (CdƥAV^2)/2 + mgsinθ
Where : m = 500 Kg
Cd = 0.35
A = 1.5 m^2
V = 11.11 m/s = 40 Km/h
θ = 0
(Note : Take θ = 0 because we made this car for plane surface only.)
F = 0.02x500x9.81 + (0.35x1.2x1.5x11.11^2)/2 + 0
= 98.1 + 77.76
F = 175.86 N
Initial Torque required :
Ti = Fr.r
= µmg x r
= 0.02x500x9.81x0.25
Ti = 24.52 Nm
Overall Torque required :
T = F.r
Where : r = 0.25 m
T = 175.86x0.25
T = 43.965 Nm
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RPM Required :
W = V/r2πN/60 = 11.11/0.25
2x3.14xN/60 = 44.44
N = 424.58 rpm
Power Required for Car :
P = T.W
= 43.965x44.44
= 1953.8 Watt
P = 1.9538 Kw
After this calculations we selected 2 kw motor for our car with following specifications :
P = 2 Kw
T = 7 Nm (approx.)
N = 3000 rpm
Differential Specifications :
Gear Ratio I : 7:1
So, after selecting 7:1 gear ratio Torque & RPM to the wheels are :
N1/N2 = T2/T1 = R
Where : N1 = 3000 rpm
T1 = 7 Nm
N1/N2 = R
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3000/N2 = 7/1
N2 = 428.57 rpm
T2/T1 = R
T2/7 = 7/1T2 = 49 Nm
Acceleration of vehicle:
F = ma
T2/r = 500xa
49/0.25 = 500xa
a = 0.392 m/s^2
Time taken to reach the speed of 40 Km/h or 11.11 m/s :
a = (V2 – V1)/t
0.392 = (11.11 – 0)/t
t = 28.34 seconds
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6.3 Suspension
Vehicle Data
It is a system of mechanical linkages, springs and dampers used to connect wheel to chassis. In
a normal car a suspension system is needed to isolate the passengers from the uneven road
surface and give a smooth ride but in a high performance car, passenger comfort is sacrificed
for better handling and road holding.
Table 6.1 : Dimensions for Suspension calculation
Table 6.2 : A-arm data
A-Arm Data:
Fig 6.5-A Arm data
Dimensions Front Rear
Wheel base 2500 mm NA
Track width 1600 mm 1600 mmCurb Weight 500 kg
Suspension System MacPherson strut Leaf spring with Hydrolic
Damper
Tire Stiffness
Tire Radius 203.2 mm 203.2 mm
Tire pressure
Length of Swing
Arm(L)
254 mm
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Roll Centre Height:
H / (T/2) = R/L
Where,
H=roll centre heightT= Track width
R=wheel Radius
L= Swing arm length
H= (T/2)×(R/L)
H= (1600/2)×(203.2/254) H=640 mm
Weight transfer Calculation
Lateral weight transfer during the Left turn of vehicle
Fig 6.6- Lateral weight transfer during the Left turn of vehicle
The Weight (W) of the car is evenly distributed among the four tires, so each tire has
W/4=1716.7 force on its contact patch.
Weight of the Body = 9.81×500
=4905 N-m/s2
Accelaration (A): 9.81 m/s2
WR ×T = W×T/2 +W×A×H
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WR =(4905×1.6 /2+500×1 G ×0.450) /1.6
WR = 2593 N
Now WL=W-WR
WL=2512 NWhere
WR = Weight on right tire
WL=weight on Left tire
T=Track width
H=Center of gravity height
Weight transfered = WR -W/2
=3630.3 -6867/2
= 140.5 N
Fractional Weight Transfered(FWT) = A×h/T =1G ×0.45/1.6
FWT= 0.281 m/s2
Weight transfer(%)= FWT×100 (%)
Weight transfer on right tire =28 % of the total weight
Longitudnal Weight transfer During Braking
Fig 6.7- Longitudnal Weight transfer During Braking
Wbrake×Wb = A×W×H
W brake= (1×4905×0.45)/2.5
W brake=882.9 N
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Where,
W brake= Weight transfer due to braking
Wb= Wheel baseDuring braking at 1G 882.9 N comes off the rear tires and onto the front tire.
Static weight distribution on was 2452.5 N on the front
And the same on rear. Now we have 1569.6 N equally divided between the rear tires and 3335
N on the front two tires.
Camber Angle Calculation:
Cornering force:
Fig 6.8-Cornering force
α= Sliping angle
Fycosα= Cornering force ǁ to path of motion v.
FySinα is perpendicular to V.
In static condition, the Total cornering force,
Fy = (Wtotal ×V2)/Rg
Here,
V=40 km/hr =11.11m/s
R=Turning radius
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= 4.98 m
Fy= 150×(11.11)2/4.98×9.81
lateral camber force,Fy= 378.98 N
Normal load, Fz =4905 NSo from the Graph, we can get the value of camber angle(ˠ) .
Fig 6.9-camber calculation
Camber angle(ˠ)= 30
Here is the Tire axis system,
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Fig 4.6-Tire axis system
Spring Stiffness Calculation
Diameter of spring wire (d) 16 mm
Mean coil diameter (D) 101.6 mm
Number of active coil (n) 9
Shear Modulus of rigidity G 79.3 Gpa (steel)
Spring force 2200 N
Table 6.3 Spring specification
By putting this value you can directly get spring stiffness from spring stiffness calculator at
http://www.tribology-abc.com/calculators/t14_1.htm
Spring stiffness= 10.5 KN/m
Spring Deflection due to load applied:
http://www.tribology-abc.com/calculators/t14_1.htmhttp://www.tribology-abc.com/calculators/t14_1.htm
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Fig 6.11- Spring Deflection due to load applied
Total weight = 4905 N
Weight on one tyre= 1226 NMoment at fixed point z is zero, so
(241×F’) + (368×1226)=0
F’=-1872 N
Fig 6.12-King pin inclination
As the Kingpin inclination is 100 , force on spring
F”= f’ cos (100)
F”=-1872×cos(100)
F”=1571 N
So, deformation of the spring due to applied load,
Stiffness= Force/Deflection
Deflection= 1571/10.5
Deflection of spring =14.6 cm
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Geometry of Front Suspension
Macphersion strut
Fig 6.13-Geometry of front suspension
Fig 6.14-Geometry of front suspension(angle calculation)
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Fig 6.15a-Mounting of front suspension(left) Fig 6.15b-Mounting of front
suspension(right)
Geometry of Rear Suspension: (leaf spring)
Fig 6.16- Geometry of Rear Suspension: (leaf spring)
Sin(45o)=BC/2.75
BC=1.94 inch
Cos(45o)= AB/2.75
AB=1.94 inch
CD2= AD2 + BC2
CD2 = (25.46)2 + (1.94)2
CD = 25.53 inc
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6.4 Braking & Wheels
6.4.1 Braking system
Type of brake 1)Hydraulic drum brake in
front
2)wired drum brake in the
Rear
Weight of car 500 Kg
Wheel base 2.5m
Track width 1.6m
Height of centre of gravityCoefficient of friction 0.7
Speed of the vehicle 40km/hr
Velocity of the vehicle 11.11m/s
Table 6.4 Data for braking calculation
Speed of the vehicle(V) =40km/h
Mass of the vehicle(m) =500 kg
Net force on vehicle(F) =Fr+Fd+mgsinθ
= μmg + (CdƥAV^2)/2 + mgsinθ
= 0.02x500x9.81 +
(0.35x1.2x1.5x11.11^2)/2 + 0
= 98.1 + 77.76
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F = 175.86 N
Where :
m = 500 Kg
Cd = 0.35
A = 1.5 m^2
V = 11.11 m/s^2 = 40 Km/h
θ = 0
(Note : Take θ = 0 because we made this car for
plane surface only.)
Accleration of the vehicle=
F=m*a
a=F/m
a=175.86/500
a =0.39572 m/s^2
Kinetic energy of the vehicle=
K.E(car)=½*mv^2
= ½*500*(11.11)^2
=30858.025 J
*since V2=0(final velocity after stopping will be zero)
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Angular velocity of wheel=
W1=v1/r
=11.11/0.35
=31.742rad/s
Since w2 will be zero due to breaking action. Vehicle is coming to
rest
Kinetic energy of 4 wheels:-
KE(wheels) =4[1/2*I(W1^2-W2^2)]
=4[1/2*(0.5)*(31.74)^2]
=1007.42 J
Total energy absorbed by four brakes consists of kinetic
energy of car[e]=
Total K.E=¼[kinetic energy of
car+kinetic energy of wheel]
=1/4[3085.025+1007.42]
=7966.36 Joule
Brake time[t]=
(V1-V2)/t=0.395g
(11.11-0)/t=0.395*9.8
11.11/3.871=t
t=2.8700s
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Stooping Distance
d = (V^2) / (a*2)
=11.11^2/(0.39572*2)
=6.97m
Torque capacity of brake=
θ =(W1/2)/t
=(31.472/2)*2.87
=45.162
Mt=E/ θ
=7966.36/45.162
=176.395 N-m
Where
E=total energy absorbed by brake
Mt=braking torque
θ =angle through which the brake drums rotates during the braking
period
After calculation:-
Net force on vehicle(F) 175.86 N
Accleration of the vehicle 0.39572 m/s^2
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Kinetic energy of the vehicle 30858.025 J
Total energy absorbed by four
brakes
7966.36 Joule
Brake time[t] 2.8700s
Stooping Distance 6.97m
Torque capacity of brake 176.395 N-m
Table 6.5 Braking Specification
6.4.2 Wheels
In modern vehicles all the primary control and
disturbance forces, which are applied to the vehicle, with the
exception aerodynamic forces are generated, in the tire road
contact patch. That has been said that ‘the critical control
forces that determine how the vehicle turns, brakes and
accelerates are developed in four contact patches ’.a thorough
understanding of the relationship between tires, their operating
conditions, and the resulting forces and moments developed at
the contact patch is an essential aspect of the dynamics of the
total vehicle.
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The tires serves essentially three basic functions:
• It supports the vehicle load, while cushioning against road
shocks.
• It develops longitudinal forces for acceleration and
braking
• It develops lateral forces while cornering
As a mechanical structure, the elastic torus of the tire is
composed of composed of a high flexible carcass of high
tensile strength cords fastened to steel-cable beads that firmly
anchor the assembly to the rim. The internal pressure stresses
the structure in such a way that any external force causingdeformation in the carcass results in a tire reaction force. The
behavioral characteristics of the tire depend not only on the
operating conditions, but on the type of the construction as
well.
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Fig 5.1-Tyre rating
Tyre rating
The tires being in the present go-kart are slick tires with the
respective tire ratings:
• Front tire rating – 20X 4 – 5.6
• Rear tire ratings – 20 X 4 – 5.6
Description:
Front tire- 20 X 4.00 –
5.6
• 20 inch= tire overall dia.
• 4.00 inch = width of the tire
• 12inch = tire rim dia.
Rear tire –
20 X 4.0 – 5.6
• 20 inch= tire overall dia.
• 4.0inch = width of the tire
• 12 inch= tire rim dia.
Tire stiffness calculation:
Maximum mass of the kart = 500kg
Weight of the kart = 500*9.81
= 4905N
weight on each front tire is = (4905*0.4)/2 = 981N
weight on each rear tire is = (4905*0.6)/2 = 1471.5N
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let the deflection under maximum pressure
on front tire be = 3mm let the deflection
under maximum pressure on rear tire be =
4mm
stiffness of front tire = (weight on front tire) / deflection = 981 / 3
= 327 N/mm
stiffness of front tire = (weight on rear tire) / deflection = 1471.5 /
4
= 367.875N/mm
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The distance between the steer axes of the steerable wheelsis called the track and is shown by w. The distance between the
front and rear axles
W
δ
i
δo
Inner
Oute
r
Wheel whe
el
A B
C
Centerof
l
a2
rotation R δi
δo
O
D C
R1
Fig 6.19. steer angles of the inner and outer wheels.
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is called the wheelbase and is shown by l. Track w and wheelbase lare considered as kinematic width and length of the vehicle.
The mass center of a steered vehicle will turn on a circlewith radius R,
R²= a2 + l2 cot2 δ (7.2)
where δ is the cot-average of the inner and outer steer angles.
cot δ =
cot δo + cot
δi
. (7.3)
2
The angle δ is the equivalent steer angle of a bicyclehaving the same wheelbase l and radius of rotation R.
Proof:
To have all wheels turning freely on a curved road, thenormal line to the center of each tire-plane must intersect at acommon point. This is the Ackerman condition.
Figure 7.2 illustrates a vehicle turning left. So, the turningcenter O is on the left, and the inner wheels are the left wheels thatare closer to the center of rotation. The inner and outer steer anglesδi and δo may be calculated from the triangles 4OAD and 4OBC as
follows:
tan δi =
l
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R 1 −
w
2
tan δo =
l
R 1 +
w
2
Eliminating
R 1
R 1 =
1
w +
l
2 tanδi
= −
1 l
w +2 tan δo
provides the Ackerman condition (7.1), which is a directrelationship between δi and δo.
w
cot δo − cot δi = (7.7)l
To find the vehicle’s turning radius R, we define an
equivalent bicycle model, as shown in Figure 7.3. The radius ofrotation R is perpendicular to the vehicle’s velocity vector v at the
mass center C. Using the geometry
We have
R 2 = a2 + R 2 (7.8)
2 1
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cot δ =
R 1
l
=
1
(cot δi + cot δo) (7.9)
2
and therefore,
R²= (7.10)a22 + l2 cot2 δ.
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The Ackerman condition is needed when the speed of the
vehicle is too small, and slip angles are zero. There is no lateralforce and no centrifugal force to balance each other. The Ackermansteering condition is also called the kinematic steering condition, because it is a static condition at zero velocity.
A device that provides steering according to the Ackermancondition (7.1) is called Ackerman steering, Ackerman mechanism,or Ackerman geom-etry. There is no four-bar linkage steeringmechanism that can provide the Ackerman condition perfectly.However, we may design a multi-bar linkages to work close to thecondition and be exact at a few angles.
Figure 7.4 illustrates the Ackerman condition for differentvalues of w/l. The inner and outer steer angles get closer to eachother by decreasing w/l.
Fig 6.20. Equivalent bicycle model for a front-wheel-steeringvehicle.
δ
V
C
l
Centerof R a2
otation δ
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O
R1
50
w/l=0.2 0.4 0.6 0.8 41.66 1.0
1.2
33.33 1.4
1.6
δi [deg] 25 2.0
16.66 w/l=3.
0
8.33
00 10 20 30
4
0 50 60 70 80
9
0
δo [deg]
Fig 6.21 Eff ect of w/l on the Ackerman condition for front-wheel-steering vehicles.
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6.5.2 Steering Mechanisms
A steering system begins with the steering wheel orsteering handle. The driver’s steering input is transmitted by ashaft through a gear reduction system, usually rack-and-pinion orre-circulating ball bearings. The steering gear output goes tosteerable wheels to generate motion through a steering mechanism.The lever, which transmits the steering force from the steering gear
to the steering linkage, is called Pitman arm.
The direction of each wheel is controlled by one steeringarm. The steering arm is attached to the steerable wheel hub by akeyway, locking taper, and a hub. In some vehicles, it is anintegral part of a one-piece hub and steering knuckle.
To achieve good maneuverability, a minimum steeringangle of approximately 35 deg must be provided at the frontwheels of passenger cars.
Tie rod
Intermediate rod
Pitman arm Idler arm
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Fig 6.22. A sample parallelogram steering linkage and itscomponents.
Rack
δS
u R
Steering box
Drag link
Fig 6.23 A rack-and-pinion steering system.
of the racks, and then by the drag links to the wheel steering δ i = δi (uR ), δo = δo (uR ). The drag link is also called the tie rod.
The overall steering ratio depends on the ratio of thesteering box and on the kinematics of the steering linkage.
6.5.3 Ackerman Steering Geometry:
The typical steering system, in a road or race car, has tie-rod linkages and steering arms that form an approximate parallelogram, which skews to one side as the wheels turn. If thesteering arms are parallel, then both wheels are steered to the sameangle. If the steering arms are angled, as shown in Figure 1, this isknown as Ackerman geometry. The inside wheel is steered to agreater angle then the outside wheel, allowing the inside wheel tosteer a tighter radius. The steering arm angles as drawn show100%Ackerman. Different designs may use more or less
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percentage pro-Ackerman, anti-Ackerman, or Ackerman may beadjustable. (In fact adjustable Ackerman is rare. This could be thecar designer saying to us, "Do not mess with this.”) Full Ackerman
geometry requires steering angles, inner wheel and outer wheel, as per Figure 1. The angles are a function of turn centre radius, wheel base and track.
.
Figure 6.24 Ackerman angle
In practise, the steering angles achieved are not perfectAckerman geometry. This is not of concern. We are only
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interested in the fact that we can have some degree of increasingdynamic toe out and that it is exponentially increasing withsteering angle. consider "Ackerman" a term to describe any
progression of dynamic toe out generated by the steeringgeometry. If it is our choice to use Ackerman, we must use a high percentage because, for small steering angles, Ackerman isminimal
We are using rack and pinion steering system having a steeringratio of 16:1
Dimensions of the vehicle are as follows
Table 6.6 Dimensions of Vehicle
Specification Dimension
Wheel base(l) 2.40 m
Tack Width(W) 1.55 mSteering Ratio 16:1
Turning Radius 5 m
Table 6.7 Formula used:
Ackerman condition Cot δₒ - cot δᵢ = W/l
Turning Radius R² = a² + L² cot² δ
δₒ is the maximum outer wheel steer angle as shown in the figure
δᵢ is the maximum inner wheel steer angle as shown in the figure
δ is the average of maximum outer and inner steer angles
a is the distance from axel to the CG
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Calculations:
1. Ackerman Steering angles
Cot δₒ - cot δᵢ = W/l
= (1.55)/(2.40)
= 0.62
By the help of hit and trail method , we calculate δₒ and δᵢ
Trail 1: if δₒ = 20 and δᵢ = 30
Cot δₒ - cot δᵢ = 2.74-1.73
= 1.01
As trail 1 is not equal to 0.62 , we proceed for trail 2
Trail 2: if δₒ = 24 and δᵢ = 30
Cot δₒ - cot δᵢ = 2.24-1.73
= 0.51
As trail 2 is not equal to 0.62, we proceed for trail 3
Trail 3: if δₒ = 23 and δᵢ = 30
Cot δₒ - cot δᵢ = 2.35-1.73
= 0.62
as trail 3 is satisfied
Therefore δₒ = 23 and δᵢ = 30
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2.Turning Radius
R² = a² + L² cot² δ
cot δ = (Cot δₒ + cot δᵢ )/2
= (2.35+1.73)/2
= 2.04
Therefore δ= 26.14
We have “a = 1m”
R² = 1²+2.4² cot²(26.14)
R = 4.98m
Therefore we have turning radius approximately 5 meter
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Chapter 7
Cost Report
_________________________________________________________
7.1 ECE Components cost report
S.No Description of Items with
specifications
Quantity
USED
Unit Price
(Rs.)
Cost (Rs.)
1.
Solar cells (monocrystalline) 300 145 43,500
2. Batteries(cells)(li-ion batteries)
3.7v 2.5 ah
8 5500 44000
3.
Motor
(2kw)+Controller+differential
1 75000 75000
4
Plexiglas sheet 30 634 19000
6. Bus ribbon(1.00 mm to 4.00
mm)
15 70/m 1050
7. UV curable adhesive 1kg 700 700
8. GSM module 1 1800 1800
9. GPS Module 1 1900 1900
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10. USB to SERIAL cable 2 250 500
11 Microcontroller(ATMEGA128) 1 750 750
12 Microcontroller(PIC16f877a) 2 200 400
13 EEP ROM( IC 24c02e) 1 200 200
14 Graphical LCD 2 600 1200
15 Tachometer 1 2000 2000
16 RF ID reader 1 2000 2000
17 Microcontroller(ATMEGA16) 1 250 250
18 P-Channel MOSFET 10 100 1000
19 Sensor(DS18b20) 1 250 250
20 LM35(Temperature Sensor) 1 100 100
21 Relay(12V, 50A) 15 100 1500
22 Electrical Wires 60m 120 7200
24 Soldering wire 1Kg 1500 1500
25 PCB(Glass Epoxy Clad Board) 10 220 2200
26 Voltage Regulating
IC(LM78XX)
10 15 150
27 Capacitor and Resistors 200 500
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28 Clamp Meter(to measure DC
current)
1 2500 2500
29 Crystal Oscillator(16MHz) 10 25 250
30 EM lock 2 3000 6000
31 Switches 50 3 150
32 Electronic Component 700
2,18,750
Table 7.1 Cost Report for ECE components
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7.2 Mechanical Components:
S.No Description of Items with specifications Quantity
USED
Unit
Price
(Rs.)
Cost (Rs.)
1 Chassis : Original
Tubular Pipes : AISI 1020
a)
Length : 22 m, Diam. : 4cm,
Thickness : 2 mm
b) L = 5 m, D = 2.5 cm, T = 3 mm
HSS : AISI 4130 / 1020a) L = 6 m, 4cmx4cmx2mm
b) L = 4 m, 5cmx5cmx1mm
Aluminum Sheet (Flour):
1.8mx1.3mx1mm
1 30000 30000
2 Suspension System :
front Suspension:- independent suspension
with mc pherson strut (Tata Nano)
rear:-leaf spring with telescopic shock
absorber (Tata Magic)
1)suspension
2)MS PLATE
3)NUTS AND BOLTS
2 set
macpherson
strut
2 set leaf
spring
3500
4200
15,400
3 Tyres :
TATA NANO
1)Tyres
1)HUB
2)RIM
4 3000 12000
4 Brakes :
TATA NANO
4 2500 10000
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1)front and rear :-
Hydraulic drum internal expanding type
1)nuts and bolts
2)Brake oil3)brake drum
4)brake pads
5 Steering system :
TATA NANO
Rack and pinion
)rack and pinion
2)steering column with rod
3)steering wheel
4)tie rods
5)nuts and bolts
1 7000 7000
6 Body works :
Glass fibre body
1)glass fibre
2)thermocole
3)plaster of paris
4)resin bond
5)hardner
6)sand paper
7)Paint
Glass fibre:10 kg
Resin bond:-75 litre
Hardner:-3 litre
90000 90000
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Table 7.2 Mechanical components Cost report
7 Chassis Paint :
Spray paint
1)f1 spray paint
2)primer3)paint thinner
4)paint catalyst
6000 6000
8 welding electrode 10 packet 150 1500
9 Fasteners 5000 5000
10 Mild Steel Plate
5 mm
2mx2m
1 2000 2000
11 Seat :
Front Seat (2)
Rear Seat (2) and seat cover
4 2000 8000
12 Accessories(light,wiper,mirror,handle,lock) NA NA 7000
13 Chassis : PVC Pipes for model
40 m
1 1000 1000
14 Pipe bending machine 1 17000 17000
Total Cost 2,11,900
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Chapter 8
Results & Discussion
________________________________________________________
8.1 DETAIL SPECIFICATIONS & FEATURES:
ENGINE AND TRANSMISSION:
Table 8.1 Engine and transmission specification
Motor Type Brushless DC Motor
Motor Power & Voltage 2 KW, 48V
Motor Torque 6.8 Nm
Motor RPM 3000
Battery Specification 48V, 80 Ah (2 sets)
Transmission Automatic
Fuel type Solar & Electric
Drive Type Rear Wheel Drive
Differential Gear Ratio 7:1
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PERFORMANCE:
Table 8.2 Performance data
Mileage 200+ km in single charge
Top Speed 40 km/h
Charging Time (Solar) 4.5 hrs
Charging Time (Electric) 2 hrs
BRAKE, STEERING, SUSPENSIONS & TYRES:
Table 8.3 Other specifications
Brake (Front & Rear) Drum
Steering Type & Steering Ratio Rack & Pinion, 16:1
Minimum Turning Radius 4.5 m
Suspension (Front & Rear) Macpherson strut, Leaf Spring
with damper
Tyre Size Radial 145/70 R-12
Wheel Size (Front & rear) 12 in
SEAT:
Sitting Capacity 5
Seat Material Foam
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DIMENSIONS AND WEIGHT:
Overall Length 3.63 m
Overall Width 1.8 m
Overall Height 1.45 m
Overall Height (door
opened)
2.2 m
Wheel Base & Track
Width
2.5 m & 1.55m
(Rear), 1.5 m
(Front)
Ground Clearance 0.25 m
Kerb Weight 500 Kg (approx.)
DRIVELINE:
Type Rear Wheel Drive
Number of driveline
modes
1
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EXTERIOR:
Body Material Glass Fibre
Frame AISI 1020 Mild Steel
Body Style Luxury
SUSPENSION:
Front Macpherson strut
Rear Leaf Spring with damper
Product Warranty:
Batteries 2 Years
Solar Cells 25 Years
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Chapter 9
Conclusion & Summary
________________________________________________________
A Solar Car which has highest mileage and can be charged by home electricity.
Fulfilling the demand of the Indian market Sun'sKaar has high efficiency, less pollution and
reduced cost.
A solar powered vehicle overcome the polluting nature of petroleum and diesel driven
vehicles, also the reduced running costs of such a vehicle makes the prospects of fully fledged
solar cars a particularly exciting one.
9.1 Highlights:
Works on Solar Energy.
Mileage greater than any other vehicle present in India.
Clean and pollution free.
Economic.
Cost Efficient.
Solar Car can save 3 INR per km in comparison with petrol cars. Solar Hybrid Cars are the
future of automotive industry.
9.2 Advantages:
The abundance of Solar Energy.
Even in the middle of winter each square meter of land still receives a fair amount of
solar radiation. Sunlight is everywhere and the resource is practically inexhaustible.
Even during cloudy days we still receive some sunlight and it is this that can be used as
a renewable resource.
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You don’t pay for sunlight
Sunlight is totally free. There is of course the initial investment for the equipment. After
the initial capital outlay you won’t be receiving a bill every month for the rest of your
life from the electric utility.
Solar energy is getting more cost effective
The technology for solar energy is evolving at an increasing rate. At present
photovoltaic technology is still relatively expensive but the technology is improving and
production is increasing. The result of this is to drive costs down. Payback times for the
equipment are getting shorter and in some areas where the cost of electricity is high
payback may be as short as five years.
Solar energy is non-polluting
Solar energy is an excellent alternative for fossil fuels like coal and petroleum because
solar energy is practically emission free while generating electricity. With solar energy
the danger of further damage to the environment is minimized. The generation ofelectricity through solar power produces no noise. So noise pollution is also reduced.
Accessibility of solar power in remote locations
Solar power can generate electricity no matter how remote the area as long as the sun
shines there. Even in areas that are inaccessible to power cables solar power can
produce electricity.
Solar energy systems are virtually maintenance free. Once a photovoltaic array is
setup it can last for decades. Once they are installed and setup there are practically zero
recurring costs. If needs increase solar panels can be added with ease and with no major
revamp.
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Chapter 10
Pictures / Images
________________________________________________________
Final
Fig 10.1-Sunskaar at Auto expo
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Manufacturing Pics
Fig 10.3-Pvc modelling
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References:
Book:
1. Heinz Heisler, Advanced Vehicle Technology, 2002, 2nd Eddition.
2. Milliken & Milliken, Race Car Vehicle Dynamics.
3.
Springer.Vehicle.Dynmics,Theory & Application, 2008.
Internet:
1. http://www.tribology-abc.com/calculators/t14_1.htm
2. http://www.carbibles.com/suspension_bible.html
3.http://www.idsc.ethz.ch/Courses/vehicle_dynamics_and_design/11_0_0_Steering_Theroy.pd
f
4. http://en.wikipedia.org/wiki/Solar_car
5. http://solarcar.stanford.edu/
6. http://inventors.about.com/od/sstartinventions/a/Solar_Cars.htm
7. http://solarcar.engin.umich.edu/
8. http://craig.backfire.ca/pages/autos/horsepower
9. http://www.speed-wiz.com/calculations/engine/index.htm
10. http://www.thecartech.com/subjects/engine/engine_formulas.htm
http://www.tribology-abc.com/calculators/t14_1.htmhttp://www.carbibles.com/suspension_bible.htmlhttp://www.carbibles.com/suspension_bible.htmlhttp://www.tribology-abc.com/calculators/t14_1.htm
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