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					Jeep   ®

                  JEEP HURRICANE
           Extreme Steering and Suspension

                        MAE 442
                      Spring 2005

                     Richard Bennett
                       Trent Boyd
                      Kyle Goodrich
                      John Walker
Jeep   ®                               A brief history

           The Jeep came into existence when the army needed to update its
           military vehicles just before entering World War II. It sent out a list of
           specifications for the new vehicle. These included:

                    ● Load capacity of 600 pounds
                    ● Wheelbase must be less than 75 inches
                    ● Engine must run smoothly from 3 - 50 mph
                    ● Rectangular shaped body
                    ● Dual range four-wheel drive
                    ● Windshield that folds down
                    ● Minimum of three-passenger seating
                    ● Blackout and driving lights
                    ● Gross vehicle weight must be less than 1200 pounds
Jeep   ®                              A brief history

               The general purpose prototype featured:

           •   A 2.2-liter four cylinder L-head style engine
           •   60 peak horsepower at 3,600 rpm for 100 hours straight
           •   Four-wheel-drive transfer case with high and low gears.
           •   An air cleaner was improved from earlier models
           •   An oil filter that was placed high up for easy accessibility
           •   A fold-up cloth roof
           •   A six volt battery to power the headlamps, which were mounted on
               swinging levers in order for them to be pointed toward the engine
               for nighttime repairs
           •   An engine that also powered the radar, radio, welding, and landing
               craft equipment
           •   Front and rear axles that were simple if very hardy beams
               suspended by equally hardy leaf springs
           •   Drum brakes at all four corners for reasonable stopping power
Jeep   ®                             A brief history

                                     The Jeep could :

           • 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.
Jeep   ®           The Future

           The Jeep Hurricane concept car
Jeep   ®                         The Future

                          Jeep Hurricane Facts and Figures

                Engine:          Two 5.7 liter, 8-cylinder HEMI engines
              Horsepower:                       670 hp
                Torque:                        740 ft-lb
             Transmission:                 5-speed automatic
             Curb Weight:                 3,850 lbs (1,746 kg)
                Length:                 151.8 inches (385.6 cm)
                Width:                   80 inches (203.2 cm)
              Wheelbase:                108.1 inches (274.6 cm)
                Wheels:                20x10 inches (51x25 cm)
                 Tires:                   305/70R20 (all four)
           0-60 mph (97 kph):                 4.9 seconds
Jeep   ®                                Suspension

           •The Hurricane has a four-wheel independent short/long-arm
           suspension system.

           •The system is dampened by coil-over shocks with remote reservoirs,
           which allows for longer travel in the shock.

           • It also sports 20-inch wheels to hold specifically designed off-roading
           tires that stand 37 inches tall.

           •Chrysler reports an angle of approach and an angle of departure of
           64 degrees and 86.7 degrees respectively.

           •The suspension sports more than 14 inches of ground clearance and
           20 inches of suspension travel.

           •The ground clearance is 5 inches greater and the suspension
           articulation is nearly triple that of Daimler-Chrysler’s most capable off-
           road Jeep production vehicle.
Jeep   ®                            Under The Hood

           •Two V8 HEMI engines.

           •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.
Jeep   ®                                   Drive Train

           •The power that the Hurricane’s engines generate is delivered to its solid
           split axles through a central transfer case that incorporates a
           mechanically controlled four-wheel torque distribution system.

           •In this system, there is a driveshaft for each wheel instead of a single
           central driveshaft.

           •Most powerful vehicles, when put under tremendous acceleration, will
           have a tendency to twist their frames or to lift one of their tires off of the
           ground. This is partially due to the fact the rotation of the driveshaft
           creates a torque on the chassis in the direction of rotation, which puts
           additional down force onto one side of the vehicle, while lifting the other

           •Conversely, the Hurricane’s split-axle design applies down force to each
           wheel individually, giving it superior traction under acceleration.
Jeep   ®   Drive Train
Jeep   ®                         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
Jeep   ®                               Performance
           •Because the Jeep Hurricane was designed with pure performance in
           mind, there are not many luxury features.

           •The body is a single piece of light-weight structural carbon fiber, which
           has remarkable rigidity for its strength. This means that the Hurricane
           can use the body as its chassis, instead of using a traditional frame.

           •All of the engine, transfer case, and suspension components are
           mounted directly to the body.

           •The skid plate of the Hurricane is an aluminum spine which also
           connects the body/chassis to the bottom of the vehicle.

           •There is also no roof, other than a few protective bars.

           •The Hurricane is only a concept prototype and will not be put into full
           production; however, Chrysler secured several patents during the
           Hurricane’s development. Now that these systems are fully functional
           and their engineers know how well these systems work, Chrysler could
           very well implement some of these technologies from the Jeep
           Hurricane into future production vehicles.
Jeep   ®                                   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.
Jeep   ®                               The Hemi


           •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

           •The thermal cycle is maximized and thus provides a higher efficiency
           or performance from the engine.
Jeep   ®                                The Hemi


           •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
Jeep   ®                                 The Hemi


           •Another reason why the HEMI engine is not used in all vehicles is the
           desire to even further minimize the combustion chamber surface area.

           •Therefore, the HEMI was designed with a “Pentroof” combustion
           chamber. The new HEMI design provides even less surface area for
           heat to be lost and four valves in the cylinder to improve conditions in
           the engine.
Jeep   ®                        The 2003 Hemi Model

           •Today’s newest HEMI engines build off the original designs of the
           first HEMI engine.
           •The new models still incorporate the hemispherical head and pride
           themselves on being the one of the most powerful and best
           performance engines in the world.
           •The 2003 Dodge HEMI carries on the tradition of HEMI engine and
           produces more power than any other listed engine and can also run
           at a higher rpm than other motors.

            Manufacturer   Size (Liters)   # of Cylinders   Horsepower   RPM
               Dodge           5.7               8             345       5400
               Dodge           8.0              10             305       4000
               GMC             6.0               8             300       4400
               GMC             8.1               8             340       4200
                Ford           5.4               8             260       4500
                Ford           6.8              10             310       4250
Jeep   ®                       Hurricane Steering

           •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
           •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
Jeep   ®                       Hurricane Steering

           The three modes of steering that this can create are:

           • Standard Steering
           • Crab Steering
           • Zero Turning Radius Steering.
Jeep   ®   Standard Steering
Jeep   ®                        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 split axel design is also shown in the illustration.

           •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.
Jeep   ®   Crab Steering
Jeep   ®                           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.
Jeep   ®   Zero Turn Radius Steering
Jeep   ®                   Zero Turn Radius Steering

           •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.
Jeep   ®       Zero Turn Radius Steering

           Jeep Hurricane in Zero Turn Radius Mode
Jeep   ®                              The Future

           •Just as the revolutionary design of the original jeep has
           influenced vehicles of the past, the new Hurricane will
           influence the vehicles of the future.
           •If adopted by the major auto manufacturers, the steering
           capabilities will drastically influence all other cars and allow
           consumers to do more with their vehicles than ever before.
           •Jeep is looking to use the new technology that has been
           developed for the Hurricane in both civilian and military
           •Although the Hurricane is very advanced, its design only
           proves that there is much more for engineers to develop in the
           advancement of the automobile.

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