252
K. Shubham et al.
Fig. 8 Front LH toe angle
distribution
-0.05
0
0.05
0.1
0.15
0.2
Toe Angle
Sample Vehices
Fig. 9 Front RH toe angle
distribution
-0.05
0
0.05
0.1
0.15
0.2
Toe Angle
Sample Vehicles
4 Subjective Evaluation of Vehicles
To find the root cause for the pulling issue, we conducted subjective evaluation of
eight vehicles numbered from V1 to V8. These selected vehicles were new vehicles
which were not driven for more than 50 km since their manufacturing. The vehicle
specifications were same as that mentioned in Table 3.
The test track selected for the subjective evaluation was a flat surface. During the
testing, it was ensured that there is no relevant wind speed to eliminate the possibility
of any crosswind causing the vehicle to pull in the direction of crosswind and test
day was selected to have stable weather conditions. Vehicles were driven in straight
line and maximum deviation from the center line along a distance of 750 m was
evaluated.
For the subjective evaluation, rating scale was used with 1 indicating almost no
deviation, 2 for low deviation, 3 for High deviation, and 4 for very high deviation.
Table 4 shows the results obtained during the subjective evaluation.
Table 4 Subjective vehicle evaluation ratings
Vehicle number Acceleration from
40 to 100 kmph 4th
gear
Constant speed
100 kmph 4th
gear
Constant speed
100 kmph 6th
gear
Coast down
clutch depressed
120–60 kmph
V1
1
1
1
1
V2
1
1
1
1
V3
2
1
1
2
V4
3
2
1
2
V5
3
2
2
3
V6
4
2
2
3
V7
4
3
3
4
V8
4
3
3
4
K. Shubham et al.
Fig. 8 Front LH toe angle
distribution
-0.05
0
0.05
0.1
0.15
0.2
Toe Angle
Sample Vehices
Fig. 9 Front RH toe angle
distribution
-0.05
0
0.05
0.1
0.15
0.2
Toe Angle
Sample Vehicles
4 Subjective Evaluation of Vehicles
To find the root cause for the pulling issue, we conducted subjective evaluation of
eight vehicles numbered from V1 to V8. These selected vehicles were new vehicles
which were not driven for more than 50 km since their manufacturing. The vehicle
specifications were same as that mentioned in Table 3.
The test track selected for the subjective evaluation was a flat surface. During the
testing, it was ensured that there is no relevant wind speed to eliminate the possibility
of any crosswind causing the vehicle to pull in the direction of crosswind and test
day was selected to have stable weather conditions. Vehicles were driven in straight
line and maximum deviation from the center line along a distance of 750 m was
evaluated.
For the subjective evaluation, rating scale was used with 1 indicating almost no
deviation, 2 for low deviation, 3 for High deviation, and 4 for very high deviation.
Table 4 shows the results obtained during the subjective evaluation.
Table 4 Subjective vehicle evaluation ratings
Vehicle number Acceleration from
40 to 100 kmph 4th
gear
Constant speed
100 kmph 4th
gear
Constant speed
100 kmph 6th
gear
Coast down
clutch depressed
120–60 kmph
V1
1
1
1
1
V2
1
1
1
1
V3
2
1
1
2
V4
3
2
1
2
V5
3
2
2
3
V6
4
2
2
3
V7
4
3
3
4
V8
4
3
3
4