Acoustic method for levitation of small living animals

Abstract

Ultrasonic levitation of some small living animals such as ant, ladybug, and young fish has been achieved with a single-axis acoustic levitator. The vitality of ant and ladybug is not evidently influenced during the acoustic levitation, whereas that of the young fish is reduced because of the inadequacy of water supply. Numerical analysis shows that the sound pressures on the ladybug’s surface almost reach the incident pressure amplitude p0 due to sound scattering. It is estimated that 99.98% of the acoustic energy is reflected away from the ladybug. The acoustic radiation pressure pa on the ladybug’s surface is only 1%–3% of p0, which plays a compression role on the central region and a suction role on the peripheral region.

TastyFloats

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Some fundamental aspects of self-levitating sliding contact bearings and their practical implementations

“…tungsten, was successfully levitated for the first time using standing wave ultrasonic levitation. Recently Xie and Wei reported the successful levitation of small living animals such as an ant, ladybird and small fish with a standing wave acoustic levitator [21] and their experiments showed that the vitality of the small animals was not impaired during levitation.…”

Measurements of the force fields within an acoustic standing wave using holographic optical tweezers

“…[1][2][3] Although initially used to measure the speed of sound in gasses, recent work has focused on exploiting this phenomena for the non-contact trapping, positioning, and manipulation of objects. 4 For example, Foresti et al used an array of transducers to levitate and manipulate millimetre sized objects in air, 2 Thalhammer et al forced living organisms into the focal plane of an optical tweezer system, 5 and Petersson et al integrated acoustic traps with a microfluidic channel to demonstrate the separation of lipids from red blood cells.…”

“…Knowledge of the stiffness of the optical trap and measurement of the micro-sphere's displacement from its equilibrium position enables the force exerted on the micro-sphere to be calculated. A single silica micro-sphere (Bang Laboratories Ltd, 5.20 lm mean diameter, variance 10%-15%, and density 2.0 g/cm 3 ) was trapped at the focus of the laser. The particle's motion was measured at 150 frames/s using image tracking.…”