Amplitude effects on virtual PMM tests

Planar Motion Mechanism (PMM) testing provides a means of determining the performance characteristics (often referred to as control derivatives or maneuvering coefficients) that populate vehicle quasi-steady state-space models. While the general nature of these tests is fairly well established, the details of execution and post processing methods vary between experimenters. This study employs numerical simulations to examine the use of a number of common force decomposition models across a range of amplitudes of oscillation. The results show that the force decomposition models examined perform similarly well at low amplitude, however accuracy appears to decline at higher amplitudes of motion with the increasing prevalence of unmodeled viscous flow phenomena.