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Jeep ® By HARISH KUMAR 11E11A0367 DEVELOPMENT OF FOUR WHEEL STEERING IN JEEP

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Operate without strain from three to 60 miles per hour
Handle a forty degree slope
Turn in a thirty foot circle
Tilt left or right on a fifty degree angle without tipping over
Run under water with attachments for air intake and exhaust.
A brief history
Each 5.7L engine generates 335 horsepower and 370lb-ft of torque.
A grand total of 670 horsepower and 740 lb-ft of torque.
Daimler-Chrysler implemented its multi-displacement system onboard the Hurricane which allows for half of an engine’s cylinders to be deactivated when the vehicle does not require as much power, thus increasing fuel efficiency.
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Steering System
The Hurricane’s revolutionary steering system is an engineering marvel in and of itself.
The Hurricane has multiple steering modes which utilize four-wheel independent steering.
This equates to each wheel having the ability to turn independently of the others and enables three different steering modes.
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The Hemi
Engines prior to the HEMI used what is called a “flathead” engine design.
The new HEMI uses a rounded, hemispherical shape in the combustion chamber, giving the unit a higher thermal efficiency and hence generating more power.
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Advantages
The obvious advantage of a HEMI engine is the amount of power it produces as compared to other engines.
The HEMI is much stronger and much more efficient.
The HEMI design has less surface area inside the combustion chamber, thus reducing the amount of area for heat to be lost.
There is less heat loss and a higher pressure peak for power to be produced.
The thermal cycle is maximized and thus provides a higher efficiency or performance from the engine.
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Disadvantages
The original HEMI engine could never produce a four valve per cylinder engine.
The valves would have to be configured in a way such that the engine would be near impossible to design and manufacture.
Drag and race cars are allowed only two valves per cylinder, making the HEMI ideal for this type of use.
Street cars do not need this extreme raw power, but rather a cylinder with more, smaller valves. This would allow the engine to breathe more efficiently and not overheat over long drives.
Another disadvantage that plagued the early HEMI designs was the emission problem due to the incomplete combustion of the fuel in the engine. Two spark plugs per cylinder helped increase the percentage of fuel combusted and hence improved the thermal cycle of the engine.
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The new Jeep Hurricane as a completely revolutionized steering system.
The Jeep Hurricane uses the innovative “T-box” mechanism to utilize three different modes of steering using a four wheel independent steering system.
The “T-box” mechanism converts the opposite rotations from each Hemi engine and converts them to four independent rotations.
Four wheel independence is achieved with the “T-box” mechanism and a split-axel design.
With all four wheels independent from each other they can all be steered independently and rotated independent of each other.
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The three modes of steering that this can create are:
Standard Steering
Crab Steering
Standard Steering
In standard steer mode the rear wheels turn in the opposite direction that the front wheels are turned.
This effect tightens the turning radius and allows for more accurate steering especially during a high speed turn.
The illustration also shows the opposing rotations from the Hemi engines and that the “T-box” mechanism rotates each individual drive shaft in different directions.
In standard steer the two drive shafts on each side of the vehicle rotate in different directions.
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Crab Steering
In crab-steer mode the rear wheels turn in the same direction that the front wheels are turned.
This effect allows the car to glide from side to side with out changing the steering of the car.
This same effect of the “T-box” mechanism is shown in the second illustration.
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The third mode of steering is zero turning radius mode.
In this mode the “T-box” mechanism allows all four wheels to toe-in at about 55 degrees.
Also, the wheels on one side of the vehicle are spinning in the opposite direction from the wheels on the other side.
This creates a pivot point at the center of the Jeep and allows the vehicle to rotate in place.
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