1. Adaptive Cruise
Control
BY
Shomik Mullick (1RV09IT040)
Siddharth D.C. (1RV09IT043)
Varun R. Athreya (1RV09IT065)
Dept. of Instrumentation Technology 1
2. Introduction
The concept of assisting driver in longitudinal
vehicle control to avoid collisions is adaptive
cruise control.
When switched on, this device takes up the task
of the task of accelerating or braking to
maintain a constant speed.
An „Adaptive Cruise Control‟ (ACC) system
developed as the next generation assisted the
driver to keep a safe distance from the vehicle
in front.
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3. Principle
ACC works by detecting the distance and speed
of the vehicles ahead by using radar system.
The time taken by the transmission and
reception is the key of the distance
measurement.
The shift in frequency of the reflected beam by
Doppler Effect is measured to know the speed.
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4. Principle
Depending on this speed, the brake and
throttle controls are done to keep the vehicle
in a safe position with respect to the other.
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5. Constituents
Inputs: Radar Beam
Delay Interval
Throttle position sensor
Brake Status
Speed calculated using speedometer
• Signals: ACC ON
Brake event(manual control)
Safe /Unsafe distance notification
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6. Constituents
Outputs : Alarms
Flashed Messages
Brake Control(Output to the
pedal system for applying emergency brake)
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8. Sensor
RADAR –
It is an electromagnetic system for the detection
and location of vehicles.
It is operated by radiating energy into space and
detecting the echo signal reflected from an
object (target) .
The reflected energy is not only indicative of the
presence but on comparison with the
transmitted signal, other information of the
target can be obtained.
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9. Sensor
The currently used „Pulse Doppler RADAR‟ uses
the principle of 'Doppler effect‟ in determining
the velocity of the target
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11. Fusion Sensor
The new sensor system introduced by Fujitsu Ltd.
and Honda
This includes millimetre wave radar linked to a
stereo camera with a 40 degree viewing angle
These two parts work together to track the car
from the non-moving objects.
Radar‟s target is the car‟s rear bumper, the
stereo camera is constantly captures all objects
in its field of view
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12. Fusion Sensor
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13. Fusion Sensor
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14. Fusion Sensor
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15. Controller Action
1. Speed control- If there is no vehicle presently
in front, then the speed is controlled about a set
point just as in conventional cruise control
2. Headway control- In order to keep a safe
distance between the vehicle s, the headway
control is required.
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17. Motorola ACC
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18. Motorola ACC
The sensor data such as Radar information, that from camera
and an IR sensor are processed.
It is a throttle controller or an engine speed controller.
It consists of
1. SRAM (1MB to10 MB)
2. FLASH 1MB
3. EEPROM (4KB to 32 KB)
4. Real time clock
5. 4 x UART interfaces
6. 3 X CAN interfaces
7. 64-bit floating point unit.
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19. Motorola ACC
The MPC 565 can be programmed to
generate the control signals
The throttle valve is actuated and the air
intake is controlled so the requirement of fuel
for the right proportion with the air also
increases.
So more fuel is injected and engine speed is
changed.
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20. Motorola ACC
HC12-
The HC12 is a breaking controller which
receives data from the wheel speed sensors and
from the DSP module.
It generates the braking control signal
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21. Motorola ACC
CAN (Control Area Network) BUS-
• CAN BUS is the network established between
controllers
• It is a 2-wire, half-duplex, high speed network
for high speed high speed applications with
short messages
It offers high speed communication rate up to
1Mbits per second and allows real time control.
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22. Motorola ACC
Each module in the ACC connected to the CAN
is called „a node‟. All are acting as transceivers
The actuator used for throttle control is a
solenoid actuator. The signal through the coil can
push or pull the plunger.
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23. Advantages
The driver is relieved from the task of careful
acceleration, deceleration and braking in
congested traffics.
A highly responsive traffic system that adjusts
itself to avoid accidents can be developed.
Since the breaking and acceleration are done in
a systematic way, the fuel efficiency of the
vehicle is increased.
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24. Disadvantages
A cheap version is not yet realized.
A high market penetration is required if a
society of intelligent vehicles is to be formed.
Encourages the driver to become careless. It can
lead to severe accidents if the system is
malfunctioning.
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25. Vehicles using ACC
Porsche Panamera
Volkswagen Passat
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26. References
Willie D. Jones, “Keeping cars from crashing.”
IEEE Spectrum September2001.
P.Venhovens, K. Naab and B. Adiprasto, “Stop And
Go Cruise Control”,
International Journal of Automotive Technology,
Vol.1, No.2, 2000.
Martin D. Adams, “Co axial range Measurement-
Current trends for Mobile
Robotic Applications”, IEEE Sensors journal, Vol.2,
no.1 Feb.2002.
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