An exact knowledge of the inertia parameters of a vehicle – like position and height of the center of gravity and the principal mass moments of inertia – are essential in many areas of automotive development and research. Examples are benchmarking activities or data collection for the implementation of valid vehicle simulation models.

fka offers a longstanding expertise in identification of the vehicle inertia parameters using the Vehicle Inertia Measurement Machine (VIMM) – a test bench for high-precision identification of vehicle inertia parameters. The VIMM consists of a spherically mounted platform actuated by three hydraulic cylinders. To identify its inertia parameters a vehicle is mounted on the platform. Within a specific test procedure which includes stationary and dynamic measurements relevant data is recorded and analyzed in a standardized post-process to determine parameters like position and height of the vehicles center of gravity as well as the principal mass moments of inertia for pitch, roll and yaw motion.

VIMM – technical information

Test bench features:

• Vehicle body rigidly fixed to the swivable measurement platform to prevent relative body motion
• Controlled spherical motion of the test-bench platform with three hydraulic cylinders
  - Max. stationary platform angle (spherical): ±20°
  - Max. dynamic platform angle (spherical): ±5°
  (at 0.6 Hz excitation frequency)
• Recording of the angular position & the forces acting on the test-bench platform

Identified vehicle parameters:

• Vehicle mass
• Position & height of the center of gravity (CoG)
• Principal mass moments of inertia (for pitch, roll and yaw)

Vehicle limitations:

• Max. vehicle mass: 2,700 kg
• Max. vehicle track width: 2,500 mm
• Max. vehicle wheel base 3,000 mm
• Special measurement configurations with vehicles beyond the stated limitations are upon request

Our services

Measurement preparations:

• Vehicle conditioning (e. g. loading with passenger dummies or dummy payload)
• Design & manufacturing of vehicle specific fixation adapters (if necessary)
• Test bench preparation

Performance of VIMM-measurements

• Measurement of test vehicles in different load configurations
• Stationary measurements for CoG identification
• Dynamic measurements or identification of principal mass moments of inertia

Data and test evaluation:

• Evaluation of test data
• Determination of inertia parameters
• Preparation of test documentation

Your testing demand

You are welcome to contact us for an individual solution for your demands in the field of CoG & inertia parameter identification.

Gallery VIMM