AS ISO 6014:2021 – Earth-moving machinery -Determination of ground speed
AS ISO 6014:2021 – Earth-moving machinery -Determination of ground speed.
3.4 Electrical supply, which may be a direct current supplied by batteries, when an inverter is required to produce an alternating current from a direct current electrical supply. Alternativel a mains alternating current may be used.
3.S Tape measure, at least 25 m in length, to determine the test track length.
3.6 Adlustable tripods, to support all light sources and photosensitive transistors at the same height.
4 Test conditions
The test may be carried out on any type of track but the test track length shall be a minimum of 20 m and in any case of sufficient length to be compatible with the speed of the machine being tested, Since the apparatus used in the test can be completely portable, it is possible to make speed measurements on gradients, on natural ground and on normal road surfaces in any condition. The time recorder shall be set up in such a way that the machine under test has a sufficiently long approach route to the test length in which to gain the speeds required, and enough room to brake, turn around and, If required, undergo a test in the opposite direction. The test track and machine conditions shall be as specified in the appropriate standard (for example. ISO 3450: for braking tests which require a knowledge of the speed of the machine, the conditions shall be as required in the Standard).
For level test tracks, the difference in height between any two points not less than 25 m apart along the test track shall not exceed 100 mm.
The cross-fall for all test tracks shall not exceed 1 in 40.
Immediately prior to the test, the machine shall be run for a period sufficient to ensure that the engine, transmission, oils and coolant are at normal working temperatures.
The machine, prepared as required, shall be driven towards the test area at a constant speed and shall be driven through the test track length without any change on the throttle setting or gearft shall be driven in a direction parallel to the longitudinal axis of the test length of the track. The time interval for a point on the machine to traverse the test track length shall be recorded.
The test shall be carried out not less than three times in each direction if the track is level, and not less than six times in one direction if the speed on a gradient is to be determined. The maximum wind speed for tests in one direction shall be 6 rn/s. The average machine speed over the test track length shall be calculated for each individual test and the mean value of all the speeds calculated and reported as the test speed.
The following accuracies shall be adhered to when conducting the tests:
The test report shall contain the following information :a)reference to this International Standard;
b)the type of machine;
c)the make of machine;
d)the number or identification of the machine;
e)whether a wheeled or tracked machine;
f)condition of the machine, for example laden or unladen, or as otherwise tested;
g)mass of machine, in kilograms;
h)Jauxiliary components attached, for example dozer blade;
i)attitude of attachment, for example “”bucket at the carry position”;
j)tyre size, ply rating,and condition;
k)tyre pressure, in kilopascals;
l)condition of the test track, i.e. wet or dry;
m) type of test track, i.e. asphalt, concrete, gravel, natural ground;
n)measured length of test track, in metres;
o)longitudinal gradient of test track, i.e. level, up gradient, down gradient;
p)cross-fall of test track;
q)machine gear at which test was conducted;
r) weather conditions，including wind speed,in metres per second, and direction relative to
the test track;
s)sany other details relevant to the particular test carried out, for example type and mode of operationof brakes, condition of machine;
y)machine speed measurements.