Numerical Analysis of Ciliary Beat in Paramecium: Increasing Ciliary Spacing as a Low Energy Cost Method for Maneuvering

In recent years, a number of patents have been devoted to designing micro robots for minimally invasive therapies inspired by Paramecium. Paramecium changes its swimming direction due to application of an external magnetic or electric field. Changing ciliary beat direction and frequency have been identified as possible methods for maneuvering through water; however, effects of variations in ciliary spacing on swimming trajectory have been poorly studied. In this work, it is aimed to analyze the effects of adjusting the ciliary spacing on swimming trajectory. For determining the swimming trajectory, Paramecium membrane is discretized to boundary elements with length of 15μm on which there are 5 cilia beating in an effective and a recovery stroke. It is observed that increasing the ciliary spacing on the upper boundary by 5% for 0.35 seconds leads to a mean 10 degrees of Paramecium rotation. This proves that even a slight error in measuring this parameter leads to great errors in determining the swimming trajectory. Also, due to lower energy consumption, variations in ciliary spacing could be an optimum means for micro robotic maneuvering. Keywords: Bio-inspired design, ciliary beat, low Reynolds locomotion, minimally invasive, Paramecium, swimming orientation.