ABSTRACT
:
A Four Wheel Turning (4WT) System
is also known as “Quadra Turning System”. In this project, both front as well
as rear wheels can be turned according to speed of the trailer and space
available for turning. Quadra turning is system that gives full size trailers
greater ease while driving at low speed, and improves stability, handling and
control at higher speed.
Quadra
Turning system works in following three phases Negative phase, Neutral phase,
Positive phase. It enables the trailer to be turned into tighter parking
spaces. It makes the trailer more stable at speed (less body roll). It makes
the trailer more efficient and stable on cornering, easier and safer lanes
change when on motorways. The turning system allows the driver to guide the moving
trailer on the road and turn it right or left as desired. The main aim is that
turning of the trailer should not require greater efforts on the part of the
driver.
The
Quadra Turning system offers a 21% reduction in turning radius. So if a trailer
is capable of making a U-turn in a 25-foot space, Quadra turn allows the driver
to do it in about 20 feet.
KEYWORDS
:
Quadra,
Negative Phase, Neutral Phase, Positive Phase.
1. INTRODUCTION
:
An
Automobile is a self–propelled vehicle which is used for the transportation of
passengers and goods upon the ground .A vehicle is a machine which is used for
the transportation of passengers and goods. A self propelled vehicle is that in
which power required for the propulsion is produced from within. Aeroplane , ship motor
boat ,locomotive ,car bus ,truck, jeep ,tractor ,scooter ,motor cycle are the example of self propelled vehicles. Motor vehicle is another name for
the self propelled and used for the transportation purposes upon the ground, so
it differs from other types of self –propelled vehicles. Like aeroplane,
helicopter, rocket, ship, motor boat, locomotive.
Automobile
engineering is a branch of engineering in which we study all about the
automobile and have practice to propel them. The words “Automotive Engineering”
is also used having the same meaning.
Mobile or motive
means one which can move. Automobile or automotive means one which itself can
move. A railway wagon cannot move itself on the rails if it is not pushed or
pulled by external force. A trolley cannot move itself on the road if it is not
pulled by external force. The railway
wagon is pulled on the rails by a locomotive. The trolley is pulled on the road
by an automobile which may be a jeep or tractor. In automobile engineering we
study about the self –propelled vehicles like car, bus, jeep, truck, tractor,
scooter, motorcycle. Aeronautical engineering deals with aeroplane, helicopter,
rocket, etc., which fly in air. Marine engineering deals with ship, motor, etc
which sail in water.
The Turning system allows the driver to guide the
moving trailer on the road and turn it right or left as desired. Further such
turning of the trailer should not require greater efforts on the part of the
driver there are mainly two types of turning system:
1.1 Conventional Turning System
Usually
during the Turning of the trailer, only the front wheels are turned towards
right or left according to the requirement and the rear wheels are mere
followers of the front wheels in this system.
1.2 Four Wheel Turning Systems
The
direction of turning the rear wheels relative to the front wheels depends on
the operating conditions. At low-speed wheel movement is pronounced, so that
rear wheels are turned in the opposite direction to that of front wheels. This
also simplifies the positioning of the trailer in situations such as parking in
a confined space. Since the rear wheels are made to follow the path on the road
taken by the front wheels, the rear of a 4WT trailer does not turn in the
normal way. Therefore the risk of hitting an obstacle is greatly reduced.
At
high speed, when Turning adjustments are subtle, the front wheels and rear
wheels turn in the same direction. As a result, the trailer moves in a
crab-like manner rather than in a curved path. This action is advantageous to
the trailer while changing lanes on a high-speed road. The elimination of the
centrifugal effect and, in consequence the reduction of body roll and cornering
force on the tyre, improves the stability of the trailer so that control
becomes easier and safer. In a 4WT system, the control of drive angle at front
and rear wheels is most essential.
The
four wheels have fully independent Turning and need to turn in an
unconventional direction to ensure that the trailer turns around on its own
axis. Such a system requires precise calculation from a servo motor with
real-time feedback to make certain that all three Turning modes function
perfectly. The only major problem posed by this layout is that a conventional rack-and-pinion
turning with pitman arms would not be suitable for this mode, since the two
front wheels are steered in opposite directions. The Hurricane jeep is having
the four wheels turning system. Steer-by-wire systems would work fine, however,
since independent control can be achieved.
2. PHASES
OF QUADRA TURNING SYSTEM :
In
this type of turning system, we can steer a front wheel, as well as the rear
wheel of the trailers simultaneously. This turning mainly includes two types of
Turning:
Front
wheels and rear wheels are steered in the same direction and are parallel to
each other. This type of system is very useful during lane changing. Front
wheels are steered in the direction opposite to that of the rear wheel. This Turning
system reduces the space required by the trailer during turning as compared to
that of the two wheels Turning system.
Quadra
Steer is the system that gives full size trailers greater ease or
maneuverability while driving or tugging trailer at low speed, and improves
stability, handling and control at higher speed. The present “Four Wheel Turning”
works mechanically with help of linkages. The system utilizes a manual
manipulator to control and direct the articulation (left and right turning) of
rear wheels.
The
system operates in three phases: - Negative, Neutral and Positive.
At
lower speeds, rear wheel turns in
opposite direction from the front wheel. This is negative phase.
At
moderate speed, the rear wheel remains
straight or neutral.
At
higher speed, the rear wheel are in
the positive phase turning in the same direction as the front wheels.
2.1 Negative Phase-
In
this drive the axles both the front and the rear move in opposite direction
relative to each other. This drive is mainly used during parking of the trailer.
As both the axle move in different directions the radius of curvature while
turning reduces. This means the trailer will require less space for parking and
this will be helpful in places where traffic and parking is a major problem
2.2
Neutral Phase-
In this drive only the front axle
moves either in clockwise or anticlockwise direction and the rear wheel being
unmoved. This is the drive that we see in day to day life in all the four
wheelers, trailer, cars etc . It is generally used at moderate speed.
2.2
Positive Phase-
As the name suggest, in this drive both the
axle viz. front and rear move in same direction relative
to the each other. This motion of both the front and the rear axle helps Quadra
Turning system enabled trailer to change the lane during highway driving [5].
It is generally applied at higher speed.
3. COMPARED
OF PROPOSED TRAILER WITH CONVENTIONAL TRAILER
MECHANISM :
- Trailer more efficient and stable on cornering.
- Improved Turning responsiveness and precision [6].
- High speed straight line stability.
- Notable improvement in rapid, easier, safer lane changing maneuvers.
- Smaller turning radius and tight space maneuverability at low speed.
- Relative Wheel Angles and their Control.
- Risk of hitting an obstacle is greatly reduced.
4. FUTURE
ASPECTS :
An
innovative feature of this Turning linkage design is its ability to drive all
four Wheels using a single Turning actuator. Its successful implementation will
allow for the development of a four-wheel, steered power base with maximum
maneuverability, uncompromised static stability, front- and rear wheel tracking,
and optimum obstacle climbing capability.
The
advanced system of “Trailer Mechanism” will work electronically with the help
or microprocessors.
The
system will utilize an onboard computer to control and direct the turning left
and right of the rear wheels.
5. CONCLUSIONS
:
Thus,
the Trailer Turning system has got cornering capability, Turning response, straight-line
stability, lane changing and low speed maneuverability. Even though it is
advantageous over the convectional trailer turning system, trailer turning is a
complex and expensive. Currently the cost of a trailer with trailer turning is
more than that of the convectional Trainer turning of trailer. Trailer Turning
is growing in popularity and it is likely to come in more and more new trailers.
As the system become more common place, the cost of four wheel Turning system
will drop down.
An innovative
feature of this turning linkage design is its ability to drive all trailers
using a single steering actuator. Its successful implementation will allow for
the development of a trailer, turning power base with maximum maneuverability,
uncompromised static stability, front- and rear-wheel tracking, and optimum
obstacle climbing capability.
Thus the trailer mechanism system has got cornering capability, turning response,
straight-line stability, lane changing and low-speed maneuverability. Even though
it is advantageous over the conventional light trailer, 4WT is complex and expensive.
Currently the cost of a trailer with Trailer mechanism is more than that for a
vehicle with the conventional trailer. Trailer mechanism is growing in
popularity and it is likely to come in more and more new trailers. As the
systems become more common place the cost of four wheel steering will drop.
6. REFERENCES :
- “Automotive Technology –A System Approach”, Jack Erjavee
- “Automotive Suspension and Turning System”, Thomas W Birch.
- “Automotive Service-Inspection, maintenance, repair” Tim Gilles
- http://www.howstuffworks.com
- http://trucks.about.com/cs/4ws/a/4wheel_Turning.htm
- http://www.theautochannel.com
- http://www.thetruckersreport.com/turning-radius-info-on-eighteen-wheelers
- Design.transportation.org/Documents/TurnRadii,GreenBook2004.pdf.
PHOTOS OF PROJECT
VIDEO OF PROJECT
Mr. KONAL
Mechanical Engineer
Ph. 09423632068
Ph. 09423632068
Director & Founder
ProBotiZ ... Steps Into Virtual Techniz
ProBotiZ Group
ProBotiZ Group
Nagpur (M.S), India – 440017
Gmail - singhkonal@gmail.com
SlideShare - http://www.slideshare.net/konalartist1
Nice and innovative Concept. I think this is not being used in trailer. If used can be beneficiary for drivers to take u turns.
ReplyDeleteGood Work Konal