ISO 9816:2018 pdf free

ISO 9816:2018 pdf free.Passenger cars – Power-off reaction of a vehicle in a turn – Open-loop test method
The constant-radius test method has the advantage of requiring only one test arc, and therefore demands less testing space than the constant-speed test. The test course is similar to curves on rural roads or exit ramps from high-speed roadways. The test method includes varying initial engine speed,and thus, varying deceleration due to engine braking. For both test methods, the initial steering wheel angle will change as lateral acceleration increases. The constant-radius test method demands some driver skill, as the test driver must establish initial steady-state cornering conditions, while following the fixed-radius path.
The constant-speed test method maintains a constant initial engine speed, and thus, a constant deceleration due to engine braking at power-off. The deceleration achieved in practice depends on the test conditions and car properties: among others, the combination of engine speed and gear needed for the chosen longitudinal velocity. This test method may be performed using either a series of fixed-radius arcs or a series of fixed steering-wheel angles, with no constraint on vehicle path. The unconstrained-path method places low demands on driver skill, as the requirement to maintain a fixed initial path is not present. The disadvantage of this test method is that a large test surface is required,particularly if high initial test speeds are to be evaluated.
The test results from the two test methods are not comparable, except for the same combination of initial path radius and speed.
Cars with adaptive gear selection or CVT may use different gears or ratios at a given speed. For such cars, engine speed shall be recorded for the purpose of determining gear ratio. It shall be recorded in the test report.
For vehicles with regenerative braking capabilities the specific vehicle configuration may alter the dynamic vehicle behaviour while releasing the accelerator pedal and/or while pressing the brake pedal.Also, the different dynamic vehicle behaviour with or without active regenerative braking shall be considered while performing the tests. The selected level of regenerative braking capability and the transmission lever position shall be documented in the test report.ISO 9816 pdf free download.