Overview
ISO 19586:2019 specifies a method for validating vehicle dynamics simulation models against measured driving tests for the lateral dynamic stability of heavy commercial vehicles and buses. The standard defines how to compare simulation outputs with physical test data (as per ISO 14791) to demonstrate that a vehicle model can reliably predict lateral behaviour for vehicle combinations such as trucks, trailers, buses and articulated buses (categories M3, N2, N3, O3, O4 per ISO 3833).
Key topics and requirements
- Purpose: Validate simulation models for lateral stability using measured test data; determine model validity ranges and tolerances.
- Test inputs: Uses the pseudo-random steer and single sine wave steering inputs defined in ISO 14791.
- Minimum model complexity: A single-track model with lateral slip behaviour is the minimum accepted model form; more detailed models are permitted if they meet parameter requirements.
- Mandatory variables to record: longitudinal velocity (vx), steering-wheel angle (δH), yaw velocity (ωz) of the first and each unit, and lateral acceleration at the front axle (ay). Recommended: yaw angle, unit CG lateral acceleration, articulation angles.
- Parameter accuracy:
- Basic parameters (must be directly measurable): axle/coupling positions (±0.02 m), axle/coupling loads (±100 kg), vehicle unit mass (±200 kg).
- Estimated parameters (used for model fitting): yaw inertia per unit (±25 %), cornering stiffness per axle (±25 %), tyre-road friction (±0.1).
- Validation procedure: Compare characteristic values from tests and simulations - notably rearward amplification (RA) and yaw damping (D) - within tolerances set by test repeatability and input uncertainty. A complete validation requires at least one tested vehicle and one variant reflected by parameter variation.
- Documentation & limits: The model must be valid in the linear range (conservative lateral acceleration limits to ensure linear behaviour). If vehicle type or tyre parameters change beyond the model’s validity range, re-validation is required.
Applications and users
ISO 19586:2019 is practical for:
- Vehicle OEMs and chassis engineers validating simulation models for truck and bus combinations.
- Simulation engineers and model developers who need to quantify model fidelity for lateral dynamics.
- Test laboratories performing ISO 14791 driving tests and comparing results to simulations.
- Regulatory and safety bodies assessing conformity of simulation-based analyses.
- Research teams studying vehicle combination stability, control systems, and active safety features.
Benefits include improved confidence in simulation-driven design, reduced physical testing needs, and standardized criteria for lateral stability model validation.
Related standards
- ISO 14791 - Lateral stability test methods (driving tests referenced)
- ISO 8855 - Vehicle dynamics vocabulary
- ISO 15037-2 - General test conditions for heavy vehicles and buses
- ISO 3833 - Vehicle classification (applicability to heavy vehicles and buses)
Keywords: ISO 19586:2019, lateral dynamic stability, vehicle dynamics simulation, validation, heavy commercial vehicles, rearward amplification, yaw damping, ISO 14791, vehicle model validation, cornering stiffness, yaw inertia, tyre characteristics.