| Several variables influence a vehicle's kinematic
behaviour:
- Test surface condition
- Environmental conditions e.g. wind speed
and direction, altitude, humidity and rain
- Vehicle configuration e.g. tyres and pressures,
suspension settings, weight, engine fittings and settings
-
Driver behaviour
Gerotek goes to considerable lengths to keep
the influence of all variables as low or constant as possible,
so as to ensure accurate, repeatable test results. The effects
of environmental conditions are minimised by the execution
of tests under specific conditions which have been found,
after years of testing experience, to have the minimum effect
on test results.
Repeatability is ensured by performing kinematic tests on
either Gerotek's High Speed or Long Straight Tracks. These
tracks are designed to test vehicles and sub-sytems under
repeatable and uninterrupted conditions with a zero percent
slope.
Kinematics can be divided into the following categories:
● Vehicle Performance
Gerotek offers various vehicle performance tests. The vehicle is fitted with a speed measuring device. All performance tests take place on Gerotek's High Speed and/or Long Straight Tracks. Complete repeatability is ensured.
Vehicle Acceleration:
Speed is measured as a function of time and distance in pre-selected increments. Speed and distance are displayed in graphical format. Typical results, which can be included, are:
Time and distance - acceleration from standstill to top speed
-
Time to complete a set distance (sprints) e.g. quarter mile, mile and kilometre
-
Time and distance - acceleration in a set gear between set speeds (tractability)
Maximum and Minimum Speed:
A vehicle's maximum and minimum speeds are measured for each gear ratio combination (forwards as well as in reverse).
● Vehicle Braking Performance:
Light or heavy vehicle braking performance is evaluated in
accordance with the national braking specifications as well
as EEC and ECE regulations.
Gerotek offers a one-stop service for brake performance testing:
- Brake testing
- Preparation of brake linings
- Verification of design and layout of brake
systems
- Fault finding
The following brake tests are offered:
- Construction and fitting requirements
- Brake efficiency and distribution among
the vehicle's axles
- Park brake evaluation
- Performance of braking system
- Reaction time measurement on compressed
air brakes
- Trailer brake evaluation
● Fuel Economy:
Today, people throughout the world are becoming increasingly
energy conscious. It is therefore vital for the transport
industry to stay abreast of these developments, and to constantly
improve on and develop more energy efficient modes of transport.
To this end, Gerotek is a forerunner in the fields of fuel
economy and consumption testing.
Services offered include:
Light vehicles (based on SANS 20084)
- Urban cycle test. This test simulates typical
driving in urban or city traffic and is structured in order
to be highly repetitive
- Constant speed test. Fuel consumption is
tested at different constant speeds on the High Speed Track
for a distance of 10 km or more.
Heavy Vehicles (based on SAE J1376-82).
- Long haul cycle. This test simulates highway
conditions and provides a basis for comparison with other
vehicles
- Short haul cycle. This test simulates inter-
and intra-city conditions
- Local cycle. This test simulates intra-city
conditions (pick-up and delivery)
- Transit cycle. This cycle reflects
driving patterns published by DOT and UMTA as the baseline
for advanced design and coach specification.
Reports are available in tabular or graphical format, or both.
Photographs and video material of the performed tests can also be provided.
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