Acoustic Levitation from Superposition of Spherical Harmonics Expansions of Elementary Sources: Analysis of Dependency on Wavenumber and Order
Paper in proceedings, 2019

Acoustic levitation of spherical objects in mid-air is a technique that is gaining traction in various human computer interaction applications such as data visualization or interactive displays. The commonly used hardware platforms are phased ultrasonic transducer arrays, used to levitate small spheres of polystyrene. Previous works have used angular spectrum decomposition of the incident sound field to derive the radiation force exerted on an arbitrary sphere. We show an alternate formulation more suited to sound fields from transducer arrays, based on direct spherical harmonics expansions of the sound fields from the individual transducer elements in the array. Finally we investigate how the truncation order of the spherical harmonics expansion influence the calculated force, for varying sphere sizes.

spherical harmonics

acoustic levitation

Author

Carl Andersson

Chalmers, Architecture and Civil Engineering, Applied Acoustics

Jens Ahrens

Chalmers, Architecture and Civil Engineering, Applied Acoustics

IEEE International Ultrasonics Symposium, IUS

19485719 (ISSN) 19485727 (eISSN)

920-923 8926167
978-172814596-9 (ISBN)

IEEE International Ultrasonics Symposium (IUS)
Glasgow, ,

Levitation with localised tactile and audio feedback for mid-air interactions (Levitate)

European Commission (EC), 2017-01-01 -- 2020-12-31.

Areas of Advance

Information and Communication Technology

Subject Categories

Physical Sciences

Signal Processing

DOI

10.1109/ULTSYM.2019.8926167

More information

Latest update

4/14/2021