BS ISO 16333:2011 Heavy commercial vehicles and buses. Steady-state rollover threshold. Tilt-table test method
BS ISO 16333 is an International Standard which provides a repeatable and discriminatory test for the steady-state rollover threshold of heavy commercial vehicles and buses. (i.e. the maximum lateral acceleration that the test vehicle could sustain in steady-state turning without rolling over.)
It is applicable to complete roll units/combinations of roll-coupled vehicle units — e.g. single-unit vehicles, tractor-semitrailer combinations, articulated buses, full trailers, B-train combinations — of commercial vehicles, commercial vehicle combinations, buses or articulated buses as defined in ISO 3833, and under Categories M3, N2, N3, O3 and O4 of ECE and EC vehicle regulations (trucks and trailers with maximum weights above 3,5 t and buses and articulated buses with maximum weights above 5 t).
It does not cover transient, vibratory or dynamic rollover situations; nor does it consider the influences of dynamic stability control systems. Furthermore, the quality of the estimate of the steady-state rollover threshold provided by the test method decreases as the tilt angle required to produce rollover increases. Even so, the results for heavy vehicles with high rollover thresholds can be used for comparing their relative steadystate roll stability.
The dynamic behaviour of a road vehicle is a very important aspect of active vehicle safety. Any given vehicle, together with its driver and the prevailing environment, constitutes a closed-loop system that is unique. The task of evaluating the dynamic behaviour is therefore very difficult since the significant interaction of these driver-vehicle-environment elements are each complex in themselves. A complete and accurate description of the behaviour of the road vehicle must necessarily involve information obtained from a number of different tests.
Since this test method quantifies only one small part of the complete vehicle handling characteristics, the results of these tests can only be considered significant for a correspondingly small part of the overall dynamic behaviour.
Moreover, insufficient knowledge is available concerning the relationship between overall vehicle dynamic properties and accident avoidance. A substantial amount of work is necessary to acquire sufficient and reliable data on the correlation between accident avoidance and vehicle dynamic properties in general and the results of these tests in particular. Consequently, any application of this test method for regulation purposes will require proven correlation between test results and accident statistics.
Contents of BS ISO 16333:
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Variables
6 Measuring equipment
6.1 General
6.2 Description
6.3 Data processing
7 Test conditions
7.1 General
7.2 Tilt-table properties
7.3 Ambient conditions
7.4 Test vehicle
8 Test procedure
8.1 Installation of vehicle on tilt-table
8.2 Test tilts
9 Data analysis
9.1 General
9.2 Tilt-table ratio
9.3 Optional data presentations
Annex A (normative) Test report — Additional test conditions
Annex B (informative) Error sources