The document discusses various topics related to automobiles including: 1. It describes the key components that make up a vehicle's powertrain including the engine, transmission, driveshaft, axles, and differential. 2. It discusses different types of engines like spark ignition petrol engines, compression ignition diesel engines, and their operating cycles. 3. It provides an overview of different automotive sensor technologies used for autonomous driving functions like cameras, radar, lidar, ultrasonic sensors, and others. 4. It outlines the SAE levels of vehicle automation from level 0 with no automation to level 5 with full automation and driverless capabilities.

1. GROUP 3 : TEAM AVERERA
Task 1
Jaynil Sheth and Khushi Kapoor

2. Energy
❏ This axle is responsible for delivering power to the driving wheels. It comes in two halves, known as half shafts, which are
connected by the differential. In most cases, rear axles are live, meaning they rotate with the vehicle's wheels.
❏ The answer to that question is that the wheel has kinetic energy in both its translational and rotational motions. It can have other
forms of energy. Such as gravitational potential energy if it's high in the air.
❏ Currently, the majority of motor vehicles worldwide are
powered by gasoline or diesel. Other energy sources include
ethanol, biodiesel, propane, compressed natural gas (CNG),
electric batteries, and hydrogen
❏ An internal-combustion engine is a heat engine in that it
converts energy from the heat of burning gasoline into
mechanical work, or torque. Engines have pistons that
move up and down inside metal tubes called cylinders.
❏ Movement of pistons is due to the tiny controlled
explosions occurring each minute, created by mixing fuel
with oxygen and igniting the mixture.
❏ The transmission transfers mechanical power from the
engine and/or electric traction motor to drive the wheels.
❏ The propeller shaft carries the power from the engine,
clutch and transmission unit to the driving wheels of the
vehicle, through the final drive and differential unit.
❏ The differential is a set of gears that transmits engine power
to the wheels, while allowing them to turn at different
speeds on turns.
Engine
Transmission
Propeller Shaft Differential
Rear Wheel Axle
Wheels
Fuel
Chemical Energy to
Mechanical Energy

3. Engines
IC Engine
Design Fuel Cycle
Number of
Strokes
Ignition
No. of
Cylinders
Arrangement
of Cylinders
Valve Cooling
EC Engine
1. Petrol
2. Diesel
3. CNG
1. Otto
2. Diesel
3. Dual
1. 4-Stroke
2. 2-Stroke
1. SI
2. CI
1. Single
2. Double
3. Multi
1. Vertical
2. Horizontal
3. Radial
4. V-Type
5. W-Type
6. Opposed
1. L
2. I
3. F
4. T
Types of Automobile Engines

4. Automobile IC Engines
Spark ignition (petrol) engine
Petrol engines take in a flammable mixture of air and petrol which is ignited by a timed spark when the charge is
compressed.
Four-stroke cycle :
These engines require four piston strokes to complete one cycle: an air-and-fuel intake stroke moving outward from the cylinder
head, an inward movement towards the cylinder head compressing the charge, an outward power stroke, and an inward exhaust
stroke.
A. Induction stroke :
The inlet valve is opened and the exhaust valve is closed. The piston descends, moving away from the cylinder head.
A. Compression stroke :
Both the inlet and the exhaust valves are closed. The piston begins to ascend towards the cylinder head.
A. Power stroke :
Both the inlet and the exhaust valves are closed and, just before the piston approaches the top of its stroke during
compression, a spark-plug ignites the dense combustible charge.
A. Exhaust stroke :
At the end of the power stroke the inlet valve remains closed but the exhaust valve is opened.
The piston changes its direction of motion and now moves from the outermost to the innermost position.
Most of the burnt gases will be expelled by the existing pressure energy of the gas, but the returning piston will push the
last of the spent gases out of the cylinder through the exhaust-valve port and to the atmosphere.

5. Two-stroke Petrol engine
A. Crankcase-to-cylinder mixture transfer :
The piston moves down the cylinder and uncovers the exhaust port (E), releasing the burnt exhaust gases to the atmosphere.
Further outward movement of the piston will uncover the transfer port (T), and the compressed mixture in the crankcase will then
be transferred to the combustion-chamber side of the cylinder.
A. Cylinder compression and crankcase induction :
The crankshaft rotates, moving the piston in the direction of the cylinder head. Initially the piston seals off the transfer port, and
then a short time later the exhaust port will be completely closed.
A. Cylinder combustion and crankcase compression :
Just before the piston reaches the top of its stroke, a spark-plug situated in the centre of the cylinder head will be timed to spark
and ignite the dense mixture.
4-stroke petrol engine 2-stroke petrol engine

6. Compression ignition (diesel) engine
• Compression-ignition (C.I.) engines burn fuel oil which is injected into the combustion chamber when the air
charge is fully compressed.
• Burning occurs when the compression temperature of the air is high enough to spontaneously ignite the finely
atomised liquid fuel. In other words, burning is initiated by the self-generated heat of compression.
Four-stroke cycle
A. Induction stroke :
With the inlet valve open and the exhaust valve closed, the piston moves away from the cylinder head.
A. Compression stroke :
With both the inlet and the exhaust valves closed, the piston moves towards the cylinder head.
The air enclosed in the cylinder will be compressed into a much smaller space.
A. Power stroke :
With both the inlet and the exhaust valves closed and the piston almost at the end of the compression stroke, diesel fuel oil is
injected into the dense and heated air as a high-pressure spray of fine particles.
The heat of compression will then quickly vaporise and ignite the tiny droplets of liquid fuel.
Expansion then follows, pushing the piston away from the cylinder head, and the linear thrust acting on the piston end of the
connecting-rod will then be changed to rotary movement of the crankshaft.
A. Exhaust stroke :
When the burning of the charge is near completion and the piston has reached the outermost position, the exhaust valve is
opened. The piston then reverses its direction of motion and moves towards the cylinder head.
The sudden opening of the exhaust valve towards the end of the power stroke will release the still burning products of
combustion to the atmosphere.

7. Two-stroke Diesel engine
• With the two-stroke-cycle engine, intake and exhaust phases take place during part of the compression
and power stroke respectively, so that a cycle of operation is completed in one crankshaft revolution or two
piston strokes.
• Since there are no separate intake and exhaust strokes, a blower is necessary to pump air into the cylinder
for expelling the exhaust gases and to supply the cylinder with fresh air for combustion.
A. Scavenging (induction and exhaust) phase
A. Compression phase
A. Power phase
2-stroke diesel engine
4-stroke diesel engine

8. Powertrains
A powertrain is an assembly of every component that thrusts your car into motion. It
includes engine, transmission, driveshaft, axles, and differential.
A powertrain is an assembly of every component that pushes the vehicle
forward. A car's powertrain creates power from the engine and delivers it
to the wheels on the ground. The key components of a powertrain include
an engine, transmission, driveshaft, axles, and differential.
• Engine: As the heart of your vehicle, an engine generates power to
drive the car.
• Transmission: A transmission is a basic component in your car that
makes sure the proper amount of power is transmitted to the wheels.
• Driveshaft: A driveshaft is a component that transfers the torque from
the transmission to the wheels.
• Axles: Axles are an important member of a powertrain. It lies between
the wheels and mainly performs two functions: first, it puts up with the
weight of the vehicle and it also rotates and transmits the power of the
engine to the wheels.
• Differential: A differential is a part of the rear axle. It allows each rear
wheel to turn at a different speed.

9. Types of Powertrains
Powertrains
Conventiona
l Powertrains
All Wheel
Drive
Front Wheel
Drive
Rear Wheel
Drive
4 Wheel
Drive
Hybrid
Powertrains
Battery
electric
vehicles
Plug-in
hybrids
Hybrid
Electric
Vehicles
Mild Hybrid
Electric
Vehicles
Fuel Cell
Electric
Vehicles
❑ BEVs are solely run on batteries. They use an electric motor to turn the wheels
and produce zero emissions.
❑ Plug-in hybrids are capable of zero emission driving, typically between 20-30
miles, and can run on petrol or diesel for longer trips
❑ Hybrid Electric Vehicles (HEVs) are capable of zero emission driving, but over a
less range than a PHEV.
❑ Mild Hybrid Electric Vehicles (MHEVs), sometimes known as hybrid assist
vehicles, have a petrol or diesel internal combustion engine equipped with an
electric motor that can allow the engine to be turned off as the car is coasting or
braking.
❑ Fuel Cell Electric Vehicles (FCEV) are zero-emission electric vehicles, which use
hydrogen fuel cells to generate power. Hydrogen – stored in an on-board fuel
tank – is combined with oxygen in the fuel cell and the only outputs are
electricity, heat and water.
❑ An all-wheel drive vehicle is one with a powertrain capable of
providing power to all its wheels, whether full-time or on-demand.
❑ Front-wheel drive (FWD) is a form of engine and transmission layout
used in motor vehicles, where the engine drives the front wheels only.
Most modern front-wheel-drive vehicles feature a transverse engine,
rather than the conventional longitudinal engine.
❑ Rear-wheel drive (RWD) is a form of engine and transmission layout
used in motor vehicles, where the engine drives the rear wheels only.
Most rear-wheel drive vehicles feature a longitudinally-mounted
engine at the front of the car.
❑ Four-wheel drive, refers to a two-axled vehicle drivetrain capable of
providing torque to all of its wheels simultaneously.

10. Braking System
Breaks
Method of
Actuation
Mechanical Hydraulic Electric Vacuum Air
Constructional
Basis
Drum Disk
Mechanical brakes arrests the
energy of a machine via force,
most commonly friction.
They uses a coarse and
rugged material that is
tightened against a body in
motion. Friction based
braking generates immense
heat and some noise.
Degrading of all engaged
surfaces occurs so inspection
and replacement is required.
Hydraulic brakes work on the
principle of PASCAL'S LAW.
Brake pedal force is
transmitted to the wheel
brakes through pressurized
fluid. Commonly used brake
fluid is Glycol Ethers or
Diethylene Glycol. Heavy
equipments uses hydraulics.
"Regenerative braking" is an
energy recovery mechanism
which slows a vehicle by
converting kinetic energy
into a form which can be
used instantly or stored until
needed. The electricity flow
causes the magnets to push
brake shoe on the drums and
apply brake.
These are currently used in
hybrid or fully electric
vehicles like Toyota Prius and
Tesla Roadster..
Braking action is produced
by creating vacuum on one
side of piston, which pushes
it and brakes are applied.
The vacuum is created by
using intake manifold.
In start there is only vacuum
on both side of piston, when
we push the brake paddle,
atmospheric pressure is
applied on one side of piston
pushing it on other side.
Air brakes uses compressed
air to operate the braking
system. When brake pedal is
pressed, the compressed air
rotates the brake cam which
in turn pushes the brake shoe
to the drum, applying brake.
These are mostly used in
heavy vehicles like trucks etc.
A brake drum is anchored
concentric to the axle hub
whereas on the axle, casing is
mounted a back plate. The
back plate is made of pressed
steel sheet and is ribbed to
increase rigidity and to
provide support. When we
press brake paddle, it pushes
the brake shoe with frictional
linings to the drum.
The disc brake has a metal
disc instead of a drum. It has
a flat shoe, or pad, located on
each side of the disc. These
two flat shoes are forced
tightly against the rotating
disc. The friction between the
shoes and the disc slows and
stops the disc.

11. Types of sensors used in an automobile
Camera Sensor :
• Used to see and interpret the objects in the road.
• By equipping cars with these cameras at every angle, the
vehicles are capable of maintaining a 360° view of their
external environment, thereby providing a broader picture of
the traffic conditions around them.
• Used detecting and recognizing objects, so the image data
they produce can be fed to AI-based algorithms for object
classification.
• Today, 3D cameras are available and utilized for displaying
highly detailed and realistic images. These image sensors
automatically detect objects, classify them, and determine
the distances between them and the vehicle.

12. Types of sensors used in an automobile
RaDAR (Radio Detection And Ranging) Sensor :
• Used to send out radio waves that detect objects and gauge their
distance and speed in relation to the vehicle in real time.
• Works best at detecting objects made of metal.
• It has a limited ability to classify objects, but it can accurately tell
you the distance to a detected object.
• Both short- and long-range radar sensors are usually deployed all
around the car and each one has their different functions. While
short range (24 GHz) radar applications enable blind spot
monitoring, the ideal lane-keeping assistance, and parking aids,
the roles of the long range (77 GHz) radar sensors include
automatic distance control and brake assistance.
• Unlike camera sensors, radar systems typically have no trouble at
all when identifying objects during fog or rain.

13. Types of sensors used in an automobile
LiDAR (Light Detection And Ranging) Sensor :
• Work similar to radar systems, with the only difference being that
they use lasers instead of radio waves.
• Apart from measuring the distances to various objects on the road,
LiDAR allows creating 3D images of the detected objects and
mapping the surroundings.
• Moreover, lidar can be configured to create a full 360° map around
the vehicle rather than simply relying on a narrow field of view.
• These two advantages have led autonomous vehicle manufacturers
such as Google, Uber, and Toyota to choose LiDAR systems for
their vehicles.

14. Other Sensors
• Ultrasonic sensors
• GPS
For engine based vehicles-
• Voltage sensor
• Engine speed sensor
• Oxygen sensor
• Mass Air Flow Sensor (MAF)
• Coolant Temperature Sensor (CTS)
• Camshaft Position Sensor
• Intake Air Temperature Sensor (IAT)
• Fuel Pressure Sensor
• Knock Sensors
• Fuel Temperature Sensor, etc

15. SAE Autonomy Levels
Level 0 - No automation :
The automated system issues warnings and may momentarily intervene but has no sustained
vehicle control. Basically, systems under this level are found in conventional automobiles.
Level 1 - Driver assistance (Hands on) :
A human driver is responsible for all tasks associated with operating the car, including
accelerating, steering, braking, and monitoring of the surrounding environment. There is a
driving automation system in the car that helps with either steering or accelerating, but not both.
Level 2 - Partial automation (Hands off) :
At this level, the automation system in the car can assist with both steering and acceleration,
while the driver is still responsible for most of the safety-critical functions and environment
monitoring. Currently, the level 2 autonomous vehicles are by far the most common on the roads.
Examples- Tesla Autopilot: tesla model - 3,S,X ,Cadillac CT6 by General Motors, Ford’s F-150 Blue
Cruise.

16. SAE Autonomy Levels
Level 3 - Conditional automation (Eyes off) :
Starting from level 3 and onward, the car itself monitors the environment by utilizing
autonomous vehicle sensors and performs other dynamic driving tasks, such as braking. The
human driver has to be prepared to intervene if a system failure occurs or other unexpected
conditions arise while driving.
Level 4 - High automation (Mind off) :
Level 4 correlates to a high level of automation, where the car is capable of completing an
entire journey without any intervention from the driver, even in extreme cases. However,
there are some restrictions: the driver can switch the vehicle into this mode only when the
system detects that the traffic conditions are safe and there are no traffic jams.
Level 5 - Full automation (Steering wheel optional) :
Fully automated cars do not yet exist, but automakers are striving to achieve level 5 of
autonomous driving where the driver simply specifies their destination and the vehicle takes
complete control and responsibility for all driving modes. Therefore, level 5 cars will have no
provisions for any human control, such as steering wheels or pedals.

18. Shell-Eco Marathon
Shell’s target is to become a net-zero emissions energy
business by 2050.
Three roles they play –
a. Energy Provider
b. Energy User
c. Partner for Change
⮚ It is a global competition for High School and
University Student Teams, Shell Eco-marathon
provides a collaborative platform to get hands-on
experience in achieving ultra-energy-efficiency.
⮚ There are two vehicle classes in Shell Eco-
marathon: Prototype and Urban Concept.
⮚ Teams must also complete several design phases.
Technical inspection is the final milestone before
gaining access to the track.
⮚ There are multiple energy categories available to
power the team's cars, reflecting the real world
need for a mosaic of energy options to power
transport. The current energy categories are:
o Internal Combustion Engine
o Battery Electric
o Hydrogen Fuel Cell
⮚ Shell Eco-marathon in 2022 will combine the best
of physical and virtual competitions!