2. Introduction
• Silicon content in automobiles has
doubled in the last 10 years and will
double again over the next five years !!!!
• Why Electronics in Automobiles ?
• Where in the Automobile ?
3. Electronics in present and future
automobiles.
SAFETY &
CONVENIENCE
BODY CONTROL POWER TRAIN DRIVER
INFORMATION
Rear Window Defogger Cruise Control Ignition Digital Gauges
Climate Control Intermittent Wiper Spark Timing Digital Clock
Keyless Entry Antitheft Devices Voltage Regulator Audio Annunciator
Automatic Door Lock Electronic
Suspension
Alternator Engine Diagnostic
Results
Light Dimmer Electronic Steering Idle Speed control Service Reminders
Traction Control Multiplex Wiring Turbo Control Miles to Empty
Antiskid Braking Hard/Soft Ride
Control
Emission System Shift Indicator
Window Control Communications Transmission
Control
Head-up Display
Airbag Restraints Load Sensitive
Braking
Diagnostics CRT Display
4. Cruise Control
• Keeps vehicle's speed constant.
• Prevents driver fatigue.
• Not suitable for all road conditions.
• Ambiguously classified as Non-Safety-
Critical.
5. Features of Cruise Control
• Below the set speed, interlocking switches and control
logic prevent the cruise control from being switched ON.
• Above the set speed, the choice to engage cruise control
rests with the driver.
• Kicks out of action immediately a very modest touch of
braking is applied.
• Not considered safe in heavy traffic, on bends, on wet or
icy roads etc.
6. Working of Cruise Control
SpeedEngine +
Transmission
Vehicle speed
sensor
Set Speed
Speed error
-
+
Proportional to
error signal
Throttle
Actuator
Road Speed
7. Working continued…
Methods of Throttle actuation
1. Electro pneumatic servo valve actuation (engine
vacuum used to provide the force via bellows).
2. Electronically controlled DC motor.
3. Stepper motor with electronic control.
8. Working continued…
Types of Electronic Control
1. Analogue + hard wired logic.
2. Digital, using a discrete cruise controller.
3. Digital cruise control function incorporated in the
engine control module.
9. Challenges implementing Cruise
Control
• A measure of protection against malfunction is taken
by :
– reducing the supply voltage to the actuator or
– Mechanically decoupling the actuator, by means of an
electromagnetic clutch.
• The above may not protect against an internal fault,
rogue signal, leading to malfunction.
• High resistance in signal lines may lead to incorrect
decoding of the states of Cruise Control switches.
• A wrongly decoded command signal or an internal fault
may cause sudden acceleration.
10. TCS & ABS
• TCS: Traction Control System
• ABS: Anti-Braking System
• TCS and ABS are strongly complimentary
systems.
• Both systems depend on accurate measurement
of wheel speed, and share a single set of wheel
speed sensors and many other control sensors.
11. GPS in Automobiles
• Orbiting 11,000 miles above the Earth, the 24 satellites
are the heart of the system.
• They constantly broadcast signals that allow any ground
receiver to calculate its distance from each satellite,
based on the delay calculations of signal.
• Each satellite carries four atomic clocks--so accurate
they lose only one second every 160,000 years.
• By capturing signals from at least three satellites, a GPS
receiver can determine which point on the Earth is the
exact distance from the satellites.
12. Applications of GPS in Automobiles
• Determine the shortest path to a particular destination.
• Getting to a known location in case someone gets lost.
• Avoiding the maximum number of tollbooths and determine the
cheapest route.
• Prevent accidents by warning us against approaching vehicles,
especially on deserted roads during the night-time.
• Provide entertainment by means of wireless radio and video links.
• Enable us to stay connected via a satellite phone, especially in
areas where cellular networks do not exist.
13. Integration Technologies in
Automobiles
• Bipolar technology was initially used in vehicles in the
first analog systems.
• BiCMOS and/or CMOS are chosen to meet the highest
performance and the highest levels of integration.
• Smart power ICs combine bipolar, CMOS and DMOS to
provide higher power levels and integration of protection
and performance features.
• Microprocessors cannot sense mechanical parameters,
can only switch low current and are low voltage devices.
16. Additional Integration at Risk
• Adding electronics to vehicles has created an
on-board energy crisis.
• A transition from 14V to 42V system is expected.
18. Hands Free Parking
Steps involved in Parking
Maneuver:
• Estimating Parking space.
• Pre-positioning of car.
• Executing the maneuver.
19. Hands Free Parking cont…
• One legal question is whether some countries
would regard a car as not being under control if
the driver’s hands were off the steering wheel.
20. Intelligent Headlamps
• Headlamps follow the steering wheel.
• Headlamps use GPS and follow the road.
• Pixel technology, based on Digital
Micrometer Device (DMD).
21. Faster Processing
• Discrete Microprocessors add to cost and
complexity.
• 32-bit processors can be included to do all
tasks.
