Spectral analysis for rod formation dynamics

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Virginia Tech


This thesis deals with the production of a continuous rod of non-uniform properties which is formed by wrapping fibers with a thin membrane. This rod is driven axially and cut into segments. Measurements of pressure, temperature, axial force, axial velocity, horizontal and vertical displacements were taken of the rod during normal operating conditions at various speeds. The time signal for these tests were converted to the frequency domain through the use of a Fast Fourier Transform (FFT). The data was then examined to determine the inputs into the rod from various components of the rod producing machine.

The results of the experiments show that the machine has inputs in several location along the production line. It also shows that changing components of the machine based on their frequency response may be beneficial in minimizing the number of stoppages in the production of the rod. This investigation into the dynamics of rod production shows that there is a potential for significant gains in production by altering certain components of the production machines. This report also offers a future test procedure that should help to better explain the rod’s motion and thus may lead to more efficient production.



signal processing, FFT, rod production, fourier