Overview
ISO 18580:2015 - "Motorcycles - Verification of total running resistance force during mode running on a chassis dynamometer" defines a standardized method to verify the total running resistance force used when measuring motorcycle exhaust gas emissions and fuel consumption on a chassis dynamometer. The standard requires comparing the measured total running resistance force (from dynamometer absorption force plus dynamometer losses and inertia contributions) with the target total running resistance force (calculated from vehicle velocity and acceleration). It is applicable when running resistance is set in accordance with ISO 11486.
Key technical topics and requirements
- Verification principle: Equivalence between target and measured total running resistance force is evaluated using linear regression analysis (slope, intercept), correlation coefficient, and relative standard deviation.
- Data acquisition: Simultaneous logging of roller speed, chassis dynamometer absorption force, and dynamometer friction loss at high resolution (sampling interval ≤ 50 ms recommended).
- Calculations:
- Target force (Ftg) derived from equivalent inertia mass, velocity and acceleration.
- Measured force (Fm) derived from absorption force, friction loss and dynamometer inertia.
- Integral work values (Wtg and Wm) and integral work error (e) to quantify energy equivalence over the test cycle.
- Tools and software:
- A/D-capable data logger with sufficient memory and sampling rate.
- Verification software that implements the regression and integral work computations described in the standard.
- Preparation and calibration: Check dynamometer calibration (roller speed, absorption force, equivalent inertia mass) and calibrate data logger inputs prior to mode running.
- Evaluation outputs: Report slope (A), intercept (B), correlation coefficient (γ), relative standard deviation (cov σ) and integral work error (ew). Acceptance criteria are to be agreed among parties.
Practical applications and users
ISO 18580:2015 is primarily used by:
- Vehicle test laboratories conducting regulated or development tests for emissions and fuel consumption.
- Motorcycle manufacturers validating test cell performance before certification testing.
- Chassis dynamometer manufacturers and service technicians for system installation and periodic performance checks.
- Regulatory bodies and conformity assessment organizations seeking consistent, reproducible dynamometer verification procedures.
Practical use cases include verifying electric-inertia dynamometers (where inertia is simulated electrically) and confirming measurement integrity prior to running standardized test cycles for emissions or fuel consumption.
Related standards
- ISO 11486 - referenced for setting running resistance force on chassis dynamometers.
Keywords: ISO 18580:2015, chassis dynamometer verification, total running resistance force, motorcycle emissions testing, fuel consumption measurement, data logger, verification software, integral work error, ISO 11486.