Experimental determination of moments of inertia for an off-road vehicle in a regular engineering laboratory

摘要

Moments of inertia play a vita! role in the motion of rigid bodies. Accurate information for moments of inertia is, however, not easily obtained for common bodies such as vehicles, aeroplanes, trains and humans. Presented in this text is a procedure, requiring minimal equipment expenditure, for the determination of the moments of inertia, for an off-road vehicle. The point of departure is rigid-body oscillation about a pivoting point, with a spring providing a restoring force. The moment of inertia about the pivoting point is then determined by both measuring the period of oscillation and calculating the gradient of the torque-angular acceleration curve. The results of the two methods for determining the pitch, roll and yaw moments of inertia of the body and chassis about the body's centre of gravity are compared. It is found that calculation is very sensitive to distance measurements and accurate determination of the position of the centre of gravity. The procedure gives results of adequate accuracy considering the experimental effort and costs involved.