ADVANCED TECHNOLOGIES USED IN AUTOMOBILES

ENERGY EFFIFIENCY The diagram above shows typical

energy uses and losses in a vehicle.

DRIVELINE LOSSES – 5.6%1. Energy is lost in the transmission and other

parts of the driveline 2. Technologies such as Automated manual

transmission (AMT) and Continuous variable transmission (CVT) are used to reduce the losses

AUTOMATED TRANSMISSION SYSTEM Automated manual transmissions combine

the best features of manual and automatic transmissions.

AMT operates similarly to a manual transmission except that it does not require clutch actuation or shifting by the driver

AMT CONTD… Automatic shifting is controlled electronically

(shift-by-wire) and performed by a hydraulic system or electric motor

Efficiency improvement: 7%

CONTINUOUSLY VARIABLE TRANSMISSION (CVT) Rather than using gears, the CVTs in

currently available vehicles utilize a pair of variable-diameter pulleys connected by a belt or chain that can produce an infinite number of engine/wheel speed ratios

CVT CONTD.. Advantages -Seamless acceleration without the jerk

or jolt from changing gears - No frequent downshifting or "gear

hunting" on hills -Better fuel efficiency

IDLING LOSSES – 17.2%1. In urban driving, significant energy is lost

to idling at stop lights or in traffic 2. Technologies such as Integrated

starter/generator (ISG) turns to reduce losses automatically by turning the engine off when vehicle is stopped and starts automatically when accelerator is pressed

ISG SYSTEMS These systems automatically turn the engine

off when the vehicle comes to a stop and restart it instantaneously when the accelerator is pressed so that fuel isn't wasted for idling. In addition, regenerative braking is often used to convert mechanical energy lost in braking into electricity, which is stored in a battery and used to power the automatic starter.

ACCESSORIES – 2.2% Air conditioning, power steering, windshield

wipers, and other accessories use energy generated from the engine.

Fuel economy improvements of up to 1% may be achievable with more efficient alternator systems and power steering systems

OVERCOMING INERTIA; BRAKING LOSSES– 5.8% move forward, a vehicle's drivetrain must

provide enough energy to overcome the vehicle's inertia, which is directly related to its weight.

The less a vehicle weighs, the less energy it takes to move it. Weight can be reduced by using lightweight materials and lighter-weight technologies

AERODYNAMIC DRAG – 2.6% A vehicle must expend energy to move air

out of the way as it goes down the road—less energy at lower speeds and progressively more as speed increases. Drag is directly related to the vehicle's shape

CONTD.. Smoother vehicle shapes have already

reduced drag significantly, but further reductions of 20-30% are possible

ROLLING RESISTANCE – 4.2% Rolling resistance is a measure of the force

necessary to move the tire forward and is directly proportional to the weight of the load supported by the tire

A variety of new technologies can be used to reduce rolling resistance, including improved tire tread and shoulder designs and materials used in the tire belt and traction surfaces

CONTD.. For passenger cars, a 5-7% reduction in

rolling resistance increases fuel efficiency by 1%

However, these improvements must be balanced against traction and noise

AUTOMOTIVE NAVIGATION SYSTEM An automotive navigation system is a

satellite navigation system designed for use in automobiles

It typically uses a GPS navigation device to acquire position data to locate the user on a road in the unit's map database.

GPS CONTD..

GPS CONTD.. Using the road database, the unit can give

directions to other locations along roads also in its database.

Dead reckoning using distance data from sensors attached to the drivetrain, a gyroscope and an accelerometer can be used for greater reliability, as GPS signal loss and/or multipath can occur due to urban canyons or tunnels.

ANTI-LOCK BRAKING SYSTEM 1. An anti-lock braking system, or ABS

is a safety system which prevents the wheels on a motor vehicle from locking up (or ceasing to rotate) while braking.

2. A rotating road wheel allows the driver to maintain steering control under heavy braking by preventing a skid and allowing the wheel to continue interacting tractively with the road surface as directed by driver steering inputs

CONTD.. While ABS offers improved vehicle control,

and may decrease stopping distances on dry and especially slippery surfaces, it can also increase braking distance on loose surfaces such as snow and gravel

OPERATION OF AN ABS The anti-lock brake controller is also known

as the CAB (Controller Anti-lock Brake). A typical ABS is composed of a central

electronic control unit (ECU), four wheel speed sensors — one for each wheel — and two or more hydraulic valves within the brake hydraulics

CONTD.. The ECU constantly monitors the rotational

speed of each wheel, and when it detects a wheel rotating significantly slower than the others — a condition indicative of impending wheel lock — it actuates the valves to reduce hydraulic pressure to the brake at the affected wheel, thus reducing the braking force

CONTD.. The wheel then turns faster; when the

ECU detects it is turning significantly faster than the others, brake hydraulic pressure to the wheel is increased so the braking force is reapplied and the wheel slows

This process is repeated continuously, and can be detected by the driver via brake pedal pulsation. A typical anti-lock system can apply and release braking pressure up to 20 times a second

OPERATION

AIR BAGS Like seat belts, the concept of the airbag -- a

soft pillow to land against in a crash -- has been around for many years

To date, statistics show that airbags reduce the risk of dying in a direct frontal crash by about 30 percent.

AIR BAGBefore:

AIR BAGAfter:

WORKING1. The bag itself is made of a thin, nylon

fabric, which is folded into the steering wheel or dashboard or, more recently, the seat or door

2. The sensor is the device that tells the bag to inflate. Inflation happens when there is a collision force equal to running into a brick wall at 10 to 15 miles per hour (16 to 24 km per hour). A mechanical switch is flipped when there is a mass shift that closes an electrical contact, telling the sensors that a crash has occurred. The sensors receive information from an accelerometer built into a microchip

WORKING3.The airbag's inflation system reacts sodium

azide (NaN3) with potassium nitrate (KNO3) to produce nitrogen gas. Hot blasts of the nitrogen inflate the airbag