hhj advanced safety system in automobiles

7/27/2019 hhj Advanced Safety System in Automobiles

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ABS Function, Design & Working

ABS types

Recent Advancements Effectiveness & Limitations

Testing & Validation

Job of the Driver

Closing Remarks


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To maintain the stability & steer-ability of the

vehicle while the wheels are impending lock or

skid in varying road conditions during braking.

To maneuver in your intended direction during

panic-stop situation.

To stop the vehicle with minimum stopping

distance.


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Consisted of Mechanical components only-Drum, Flywheel.

Relative angular speed difference between Drum & Flywheel causes some

drop in main hydraulic line & thereby reducing brake pressure in the

adequate amount.


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Operation-Wheel speed sensor (A) senses the abnormal spinning of the

wheel .-Signal(input strength) is sent to the ECU (B).

-ECU processes it & communicates with HCU (C) to increase ordecrease the brake pressure Tin the brake line (D) to the affected

wheel.


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INPUT TOABS

PROCESSING

OUTPUT-OPTIMUMBRAKING PRESSURE


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ABS Function, Design & Working.

ABS types.

Recent Advancements. Effectiveness & Limitations.

Testing & Validation.

Job of the Driver.

Closing Remarks.


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Four-channel, four-sensor ABS-This is the best scheme. There is a speed sensor on all four

wheels and a separate valve for all four wheels. With this setup, the controller monitors each

wheel individually to make sure it is achieving maximum braking force.

Three-channel, three-sensor ABS-This scheme, commonly found on pickup trucks with

four-wheel ABS, has a speed sensor and a valve for each of the front wheels, with one valve

and one sensor for both rear wheels. The speed sensor for the rear wheels is located in the

rear axle.

One-channel, one-sensor ABS-This system is commonly found on pickup trucks with rear-

wheel ABS. It has one valve, which controls both rear wheels, and one speed sensor, located

in the rear axle.


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ABS Function, Design & Working.

ABS types.

Recent Advancements. Effectiveness & Limitations.

Testing & Validation.

Job of the Driver.

Closing Remarks.


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Function-The job of the EBD as a subsystem of the ABS

system is to control the effective adhesion utilization by the

rear wheels & it automatically varies the amount of force appliedto each of a vehicle's brakes, based on road conditions, speed,

loading/weight, etc.

The pressure of the rear wheels is approximated to the ideal

brake force distribution in a partial braking.

EBD can apply more or less braking pressure to each wheel in order

to maximize stopping power whilst maintaining vehicular control.


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http://localhost/var/www/apps/conversion/tmp/scratch_10/corollaEBD.wmv


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FUNCTION- To prevent loss oftraction of the driven road wheels, and therefore maintain the

control of the vehicle when excessive throttle is applied by the driver (rapid acceleration) and

the condition of the road surface (due to varying factors) is unable to cope with

the torque applied.

The intervention can consist of one or more of the following:

Retard or suppress the spark to one or more cylinders.

Reduce fuel supply to one or more cylinders.

Brake one or more wheels.

Close the throttle.

In turbo-charged vehicles, the boost control solenoid can be actuated to reduce boost and

therefore engine power.
http://localhost/var/www/apps/conversion/tmp/scratch_10/TCS.mp4http://localhost/var/www/apps/conversion/tmp/scratch_10/TCS.mp4


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ABS types



Job of the Driver

Closing Remarks


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Reduces the risk of multiple vehicle crashes by 18 percent,

Reduces the risk of run-off-road crashes by 35 percent.

On high-traction surfaces such asbitumen, orconcrete, ABS reduces

stopping distances.

Better than Threshold braking.

Reduces chances of skid & hence maintains the stability &

steer-ability.

Reduces wear & tear of tires.
http://en.wikipedia.org/wiki/Bitumenhttp://en.wikipedia.org/wiki/Concretehttp://en.wikipedia.org/wiki/Concretehttp://en.wikipedia.org/wiki/Bitumen


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ABS fails to function when all wheels get locked

during braking.

Drivers of vehicles equipped with ABS tend to be

careless or overconfident (psychological influence).


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ABS types



Job of the Driver

Closing Remarks


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Stability & Steer-ability.

Full braking on a curve & swerving.

Stopping distance.

More control on varying road conditions.


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ABS types



Job of the Driver

Closing Remarks


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In order for ABS to Function effectively, driver should

press the brake pedal as hard as possible.

Do not put off your feet from the pedal if you sense

pulsing(-it indicates that ABS is working).

Driver should normally steer the vehicle to its intended

direction.

Don't release the pedal until you have safely stopped.
http://localhost/var/www/apps/conversion/tmp/scratch_10/3S%20RULES.wmvhttp://localhost/var/www/apps/conversion/tmp/scratch_10/3S%20RULES.wmv


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ABS Function, Design & Working ABS types

Recent Advancements Effectiveness & Limitations Testing & Validation Job of the Driver Closing Remarks


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Today ABS is a utmost necessary advanced safety feature

in almost any automobile.

EBD, ESC & TCS assist ABS depending on their specificcapabilities and functions.

Even an alert skilled driver would find it difficult without

ABS to match the performance of vehicle with ABS.

Even if your vehicle has ABS, Be attentive while driving.


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hhj advanced safety system in automobiles

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