Road Vehicle Performance, Meaning, Importance & Its Elements

Road vehicle performance | src: Siemens PLM

There are many design standards used in highway and
traffic analysis. Basic understanding of the performance of vehicles is pivotal
to effectively comprehending the aforesaid.

For instance, we do know that the determination of the
length of freeway and arterial acceleration lanes, maximum highway grade,
stopping sight distances passing sight distances, and numerous accident
prevention devices all hinge upon a basic knowledge of vehicle performance.

In the same vein, vehicle performance is a major consideration
in the selection and design of traffic control devices, the determination of
speed limits, and the timing and coordination of traffic signals.

Study of rad vehicle performance serves two important
functions viz-a-viz, the provision of an understanding of the highway design
and operational control compromises necessary to accommodate the wide variety
of vehicles typically encountered on the road, and the formation of the basis
from which the impact of advancing vehicle technologies on existing highway
design standards can be assessed.

Some elements of road vehicle performance due to the
straight-line performance of vehicles (acceleration, deceleration, ability to
ascend grade, top speed) are:

(a)   Tractive
Effort and Resistance

(b)   Aerodynamic
Resistance

(c)   Rolling
Resistance

(d)   Grade
Resistance

(e)   Available
Tractive Effort

(f)    Vehicle
Acceleration

(g)   Principles
of Braking

(h)   Distance
Travelled during Perception/Reaction