Micro propulsion in liquid by oscillating bubbles

This paper presents a micro propelling mechanism that may be possibly used to propel a micro medibot (medical robot) that can swim inside of animal/human bodies. A key contribution of this work is that, to our best knowledge, for the first time we microfabricate micro propelling devices based on bubble oscillation and prove the propelling mechanism in micro scale. The measured propelling speed is up to 45 mm/s and the generated propelling force is estimated to be up to 6 μN, which is strong enough not only to propel the propelling device itself but also to carry a large attached object of even several millimeters.