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K. Shubham et al.
1 Introduction
Vehicle pulling is a motion of vehicles in lateral direction on a straight road and at
a constant speed, without application of any load on the steering wheel; it is also
known as vehicle residual aligning torque (VRAT) [1]. A vehicle with the pulling
issue would require a constant correction of vehicle direction to maintain the vehicle
on a straight line. Driving a vehicle that is pulling is not only uncomfortable and
irritating for the driver but also dangerous from a road safety perspective [2]. The
motivation behind this study is to perform an in-depth analysis of vehicle pulling
phenomenon and propose general guidelines to systematically identify the root cause
and find corrective measures for its resolution.
Vehicle pull is attributed to different factors. Understanding what can effect it is
imperative for resolution of the pulling issue in any vehicle. Major factors that cause
vehicle pulling problem are tire conicity, PRAT, road crown, cross camber, cross
castor, cross wind, and various other manufacturing constraints [3–5].
This article initially outlines basic vehicle attributes that have an impact on the
vehicle pulling. Then, the details of the study that was conducted to check the wheel
alignment data for the vehicles that were reported for vehicle pulling from the field
with reference to the specified standards in design.
Based on the observations and experiments conducted, a generalized procedure
is established for resolution of vehicle pulling issue for the future reference as a
guideline.
2 Vehicle Pulling Checking Procedure
Following procedure was followed for checking if the vehicle has a pull or not.
1. Before stesting the test, verified that the tires are original, as provided by
the vehicle manufacturer and are set to the inflation pressure as per vehicle
specifications.
2. Located a road for testing the vehicle which meets the following criteria.
a. Road slope not more than 1.7°.
b. One or a multiple lane road.
c. Straight road for at least 250 m.
d. Lane width to be between 3 m and 3.5 m.
3. Cautions ensured:
a. Conducted the test on a flat amd even road without bumps or grooves.
b. Did not tested on the roads having an excessive crown.
c. Conducted the test on uncrowned road and ensured that the safety precautions
are ensured.
d. Ensured that there is no strong cross wind during the testing.
K. Shubham et al.
1 Introduction
Vehicle pulling is a motion of vehicles in lateral direction on a straight road and at
a constant speed, without application of any load on the steering wheel; it is also
known as vehicle residual aligning torque (VRAT) [1]. A vehicle with the pulling
issue would require a constant correction of vehicle direction to maintain the vehicle
on a straight line. Driving a vehicle that is pulling is not only uncomfortable and
irritating for the driver but also dangerous from a road safety perspective [2]. The
motivation behind this study is to perform an in-depth analysis of vehicle pulling
phenomenon and propose general guidelines to systematically identify the root cause
and find corrective measures for its resolution.
Vehicle pull is attributed to different factors. Understanding what can effect it is
imperative for resolution of the pulling issue in any vehicle. Major factors that cause
vehicle pulling problem are tire conicity, PRAT, road crown, cross camber, cross
castor, cross wind, and various other manufacturing constraints [3–5].
This article initially outlines basic vehicle attributes that have an impact on the
vehicle pulling. Then, the details of the study that was conducted to check the wheel
alignment data for the vehicles that were reported for vehicle pulling from the field
with reference to the specified standards in design.
Based on the observations and experiments conducted, a generalized procedure
is established for resolution of vehicle pulling issue for the future reference as a
guideline.
2 Vehicle Pulling Checking Procedure
Following procedure was followed for checking if the vehicle has a pull or not.
1. Before stesting the test, verified that the tires are original, as provided by
the vehicle manufacturer and are set to the inflation pressure as per vehicle
specifications.
2. Located a road for testing the vehicle which meets the following criteria.
a. Road slope not more than 1.7°.
b. One or a multiple lane road.
c. Straight road for at least 250 m.
d. Lane width to be between 3 m and 3.5 m.
3. Cautions ensured:
a. Conducted the test on a flat amd even road without bumps or grooves.
b. Did not tested on the roads having an excessive crown.
c. Conducted the test on uncrowned road and ensured that the safety precautions
are ensured.
d. Ensured that there is no strong cross wind during the testing.