What Is Center Of Gravity And Inertia Testing

The Vehicle Inertia Measurement Facility product line performs measurement of center of gravity and inertia properties. The original VIMF design is proved to be sturdy, extremely accurate and trusted. The VIMF was redesigned using upgraded exemplary automation, improved ergonomics and control system, along with providing the superior level of high-quality vehicle mass measurements, vehicle inertia and center-of-gravity properties.

These upgraded features are built so that the current VIMF machines can easily be retrofitted with the brand-new features. Let us learn more about Center Of Gravity And Inertia Testing and the way it is performed.

Components of Center Of Gravity And Inertia Testing

A machine is built to measure the mass, inertia matrix, center of gravity location, and products of inertia. These quantities are beneficial in studying vibrations of an engine, calculation of the torque axis, and also in the location of engine mounts. As the machine got developed mainly for engines, it can also be used for objects of same weight and size, and smaller objects like wheels, rims or tires.

The entire product line of VIMF has expanded its services in the past few years with arrangements to accommodate small sized vehicle components, passenger vehicles, engines, large sized military and commercial vehicles. VIMF gravity and inertia testing for vehicles come in the range from 450kg to 45,000 kg capacity.

Features of testing machine

One of the major features of the testing device is placement of the object on the test table. This object never changes its orientation at the time of the test cycle. This lessens the testing duration to one hour or less than an hour with only a few minutes to hours of setup time as per the complexity of the object shape. Other test methods of inertia can need separate CG measurement, and up to 5 reorientation to perform the test.

How does the testing machine perform?

The machine device makes use of a system that comprises of springs, 3 sensors and pivots to get the 3 moments and 3 inertia products along with the CG location. The mass of the object is calculated separately on this scale.

A stable arrangement of pendulum is used to obtain the CG location, 2 moments and 1 product of inertia. This device has a rotating plate made with springs to get 1 moment of inertia. A load cell helps in getting 2 products of inertia.

There are 3 sensors built into the machine. These are an inclinometer, a rotary encoder as well as a load cell. Customized software tracks the measurements sensed from the sensors. Testing software performs all types of calculations, checks for testing errors as well as guide them through the entire test sequence.

The vehicle is assisted on air bearing that is permitted to oscillate in a specified defined alignment against the spring resistance. The total time of oscillation gets computed and the inertia is calculated. The gravity center is measured in 3 directions with a little inclination of a vehicle over some degrees and computations performed with a load cell.


Hope this article has helped you in understanding the components and working of the device used in performing center of gravity and inertia testing.