Physical experiment and computer simulation of the speed-up manoeuvre using the absolute nodal coordinate formulation

This paper presents an experimental validation of the absolute nodal coordinate formulation spatial element with the speed-up manoeuvre. A long, thin steel beam with a circular cross-section is analysed. The beam is fixed at the middle with the clamp that itself is attached to the brushless motor housing. The drive is controlled by a dedicated speed controller and the final speed is set by adjusting the PWM signal level. The position of specific points at the beam and the drive is measured by attached markers with a high-speed camera that records the picture with 2400 frames per second. The position of the rotor is then used as input for further multibody dynamic analysis. The top rotational speed of the rotor is far larger than the critical speed for the linear floating frame of reference model. The beam is modelled with a continuum-based, standard, curved, two-node absolute nodal coordinate formulation beam element. As Poisson locking often occurs in thin absolute nodal coordinate formulation beams, selective reduced integration is employed to alleviate the locking influence. The air drag is modelled with a simple model of idealised air flow around the cylinder. A comparison of the experimental and the computer simulation reveals a good agreement between the results.