Specifications
Brake assessment manual Ver 1.0 Published October 2013 15 (48 pages)
Appendix 1: Glossary
The terms below are used in this Appendix. Except for those marked with an asterisk (*),
they have been taken from “Australian Design Rules – Definitions and Vehicle Categories”;
and those marked (
†
) have been amended specifically for this Manual. To identify where they
are used, they are italicised in the text.
Antilock System - a portion of a service brake system that automatically controls the degree
of rotational wheel slip relative to the road at one or more road wheels of the vehicle during
braking
Average Deceleration - the number determined by dividing the square of the initial vehicle
speed by twice the stopping distance expressed in compatible units.
Axle - one or more shafts positioned in a line across a vehicle, on which one or more wheels
intended to support the vehicle turn.
Axle Load - total load transmitted to the road by all the tyres of all the wheels whose centres
may be included between two transverse parallel vertical planes less than one metre apart.
Brake Power Assist Unit - a device installed in a hydraulic brake system that reduces the
operator effort required to actuate the system and that if inoperative does not prevent the
operator from braking the vehicle by a continued application of muscular force on the service
brake Control.
Brake Power Unit - a device installed in a Brake System that provides the energy required to
actuate the Brakes, either directly or indirectly through an auxiliary device, with the operator
action consisting only of modulating the energy application level.
Brake System - all those systems and devices attached to the vehicle whose primary
function is to translate energy and/or muscular effort of the driver, or in the case of trailers,
energy and/or information supplied by the towing vehicle into a force that restrains vehicle
movement.
Brakes - those Friction Elements that are forced together by the influence of the remainder of
the brake system so as to apply a restraining torque to the vehicle wheels.
* Cold brakes - brakes whose discs’ temperature is between 65ºC and 100ºC.
Control - a component actuated directly by the operator to transmit the force required to
activate the brake system.
* Fade - reduction in braking effectiveness caused by excessive heat that can occur after
repeated or sustained application of the brakes.
Friction Element - a part of the system designed for replacement and which contacts another
part of the system in such a way that either vehicle kinetic energy is dissipated or the vehicle
is restrained from moving.
Gross Vehicle Mass - the maximum laden mass of a motor vehicle as specified by the
Manufacturer.
Lightly Loaded Test Mass (LLTM) - the mass of the Unladen vehicle with a full capacity of
lubricating oil and coolant and not less than 75% of full fuel capacity but without goods,
occupants or options except those options which are essential for the test procedures
specified, plus additional loading distributed in the seating position adjacent to the driver’s
seating position so that the mass of such loading plus the mass of the driver and
instrumentation mounted in the vehicle is 155 ± 30 kg.
M Category Vehicles
MA Passenger Car - a passenger vehicle, not being an off-road passenger vehicle or a forward-
control passenger vehicle, having up to 9 seating positions, including that of the driver.