Calculation Methods; Deceleration; Out-Of-Roundness; Road Surface Adhesion - Bosch BSA 43 Series Original Instructions Manual

en 72 | BSA 43xx | Appendix
10.2

Calculation methods

10.2.1

Deceleration

Deceleration is a measure of the performance of a bra-
king system. It is specified as the percentage ratio of
braking force to weight.
Axle deceleration
F
axis
Z = x 100 %
G *g
axis
Z Deceleration in percent
F Axle braking force
axis
G Axle weight
axis
g Acceleration due to gravity
Total deceleration
F + F
front rear
Z = x 100 %
G *g
total
Z Deceleration in percent
F Front axle braking force
front
F Rear axle braking force
rear
G Total weight
total
G Vehicle weight
vehicle
G Weight of tester
test person
g Acceleration due to gravity
Parking brake deceleration
F
hand
Z = x 100 % , G
total
G *g
total
Z Deceleration in percent
F Braking force of parking brake
hand
G Total weight
total
G Vehicle weight
vehicle
G Weight of tester
test person
g Acceleration due to gravity
|
1 691 606 210 2015-07-29
, G = G + G
total vehicle test person
= G + G
vehicle test person
10.2.2

Out-of-roundness

The pedal force is kept constant. The BSA 43xx measures
the resultant minimum and maximum braking force. The
out-of-roundness is calculated as follows:
F - F
max min
(~) = x 100 %
F
max
(~) Out-of-roundness in percent
F Maximum braking force
max
F Minimum braking force
min
10.2.3

Road surface adhesion

Road surface adhesion is calculated as the ratio be-
tween the minimum dynamic wheel load in the resonant
range and the static wheel load.
RD
?
( ) = x 100 %
RS
(↓) Road surface adhesion in percent
RD Minimum dynamic wheel load
RS Static wheel load (weight)
u
Evaluation
( )
60 – 100 % Good
40 – 59 % Adequate
20 – 39 % Critical
0 – 19 % Inadequate
Evaluation display
(analog display)
Green
Yellow
Red
Red
Robert Bosch GmbH